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Document and Entity Information - USD ($) shares in Millions	12 Months Ended
	Jan. 28, 2017	Mar. 22, 2017	Jul. 29, 2016
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Jan. 28, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	FY
Trading Symbol	MRVL
Entity Registrant Name	MARVELL TECHNOLOGY GROUP LTD
Entity Central Index Key	0001058057
Current Fiscal Year End Date	--01-28
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity File Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		502.4
Entity Public Float			$ 3,844,207,456

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Current assets:
Cash and cash equivalents	$ 814,092	$ 1,278,180
Short-term investments	854,268	1,004,569
Accounts receivable, net of provision for sales returns and allowances of $1,384 and $2,762 in fiscal 2017 and 2016, respectively	335,384	323,300
Inventories	171,969	200,958
Prepaid expenses and other current assets	58,771	102,560
Assets held for sale	45,846	45,095
Total current assets	2,280,330	2,954,662
Property and equipment, net	243,397	296,778
Long-term investments	4,615	11,296
Goodwill	2,003,413	2,003,413
Acquired intangible assets, net	3,571	11,947
Other non-current assets	113,324	164,031
Total assets	4,648,650	5,442,127
Current liabilities:
Accounts payable	143,484	180,372
Accrued liabilities	143,491	132,060
Carnegie Mellon University accrued litigation settlement	0	736,000
Accrued employee compensation	139,647	121,631
Deferred income	68,124	53,973
Current liabilities held for sale	1,670	1,749
Total current liabilities	496,416	1,225,785
Non-current income taxes payable	60,646	49,256
Other non-current liabilities	63,937	26,963
Total liabilities	620,999	1,302,004
Commitments and contingencies (Note 10)
Shareholders’ equity:
Preferred stock, $0.002 par value; 8,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.002 par value; 992,000 shares authorized; 506,095 and 507,572 shares issued and outstanding in fiscal 2017 and 2016, respectively	1,012	1,015
Additional paid-in capital	3,016,775	3,028,921
Accumulated other comprehensive income (loss)	23	(795)
Retained earnings	1,009,841	1,110,982
Total shareholders’ equity	4,027,651	4,140,123
Total liabilities and shareholders’ equity	$ 4,648,650	$ 5,442,127

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Statement of Financial Position [Abstract]
Accounts receivable, provision for sales return and allowances	$ 1,384	$ 2,762
Preferred stock, par value (in usd per share)	$ 0.002	$ 0.002
Preferred stock, shares authorized	8,000,000	8,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in usd per share)	$ 0.002	$ 0.002
Common stock, shares authorized	992,000,000	992,000,000
Common stock, shares issued	506,095,000	507,572,000
Common stock, shares outstanding	506,095,000	507,572,000

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Income Statement [Abstract]
Net revenue	$ 2,317,674	$ 2,649,216	$ 3,637,206
Operating costs and expenses:
Cost of goods sold	1,029,527	1,442,517	1,799,425
Research and development	831,398	994,733	1,091,547
Selling and marketing	115,817	124,096	139,627
General and administrative	127,376	145,359	124,046
Carnegie Mellon University litigation settlement	0	654,667	0
Restructuring and other related charges	105,186	53,251	10,438
Amortization and write-off of acquired intangible assets	8,376	10,098	15,747
Total operating costs and expenses	2,217,680	3,424,721	3,180,830
Operating income (loss)	99,994	(775,505)	456,376
Interest and other income, net	17,022	17,685	23,334
Income (loss) from continuing operations before income taxes	117,016	(757,820)	479,710
Provision (benefit) for income taxes	73,022	11,335	(4,077)
Income (loss) from continuing operations	43,994	(769,155)	483,787
Loss from discontinued operations, net of tax	(22,843)	(42,245)	(48,441)
Net Income (loss)	$ 21,151	$ (811,400)	$ 435,346
Net income (loss) per share - Basic:
Continuing operations (in usd per share)	$ 0.09	$ (1.51)	$ 0.95
Discontinued operations (in usd per share)	(0.05)	(0.08)	(0.10)
Net Income (loss) per share basic (in usd per share)	0.04	(1.59)	0.85
Net income (loss) per share - Diluted:
Continuing operations (in usd per share)	0.09	(1.51)	0.93
Discontinued operations (in usd per share)	(0.05)	(0.08)	(0.09)
Net Income (loss) per share diluted (in usd per share)	$ 0.04	$ (1.59)	$ 0.84
Weighted average shares:
Basic (in shares)	509,738	510,945	511,089
Diluted (in shares)	517,513	510,945	520,760
Cash dividends declared per share (in usd per share)	$ 0.24	$ 0.24	$ 0.24

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 21,151	$ (811,400)	$ 435,346
Other comprehensive income (loss), net of tax:
Net change in unrealized gain (loss) on marketable securities	(145)	(4,424)	1,234
Net change in unrealized loss on auction rate securities	0	2,274	597
Net change in unrealized gain (loss) on cash flow hedges	963	1,047	(2,120)
Other comprehensive income (loss), net of tax	818	(1,103)	(289)
Comprehensive income (loss), net of tax	$ 21,969	$ (812,503)	$ 435,057

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Balance (in shares) at Feb. 01, 2014		502,405
Balance at beginning of period at Feb. 01, 2014	$ 4,675,910	$ 1,005	$ 2,941,650	$ 597	$ 1,732,658
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to stock options and awards (in shares)		9,673
Shares issued pursuant to stock options and awards	38,039	$ 19	38,020
Issuance of common stock under the employee stock purchase plan (in shares)		9,690
Issuance of common stock under the employee stock purchase plan	74,318	$ 19	74,299
Cancellation of restricted stock units for net share settlement (in shares)		(1,661)
Cancellation of restricted stock units for net share settlement	(26,494)	$ (3)	(26,491)
Share-based compensation	137,001		137,001
Tax benefit (deficiency) from employee stock transactions	$ 21		21
Repurchase of common stock (in shares)	(5,100)	(5,070)
Repurchase of common stock	$ (64,962)	$ (10)	(64,952)
Cash dividends declared and paid (cumulatively $0.24 per share)	(122,801)				(122,801)
Net income (loss)	435,346				435,346
Other comprehensive income (loss)	(289)			(289)
Balance (in shares) at Jan. 31, 2015		515,037
Balance at end of period at Jan. 31, 2015	5,146,089	$ 1,030	3,099,548	308	2,045,203
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to stock options and awards (in shares)		8,022
Shares issued pursuant to stock options and awards	21,779	$ 16	21,763
Issuance of common stock under the employee stock purchase plan (in shares)		5,890
Issuance of common stock under the employee stock purchase plan	58,938	$ 11	58,927
Cancellation of restricted stock units for net share settlement (in shares)		(1,677)
Cancellation of restricted stock units for net share settlement	(24,358)	$ (3)	(24,355)
Share-based compensation	133,766		133,766
Tax benefit (deficiency) from employee stock transactions	$ 108		108
Repurchase of common stock (in shares)	(19,700)	(19,700)
Repurchase of common stock	$ (260,875)	$ (39)	(260,836)
Cash dividends declared and paid (cumulatively $0.24 per share)	(122,821)				(122,821)
Net income (loss)	(811,400)				(811,400)
Other comprehensive income (loss)	(1,103)			(1,103)
Balance (in shares) at Jan. 30, 2016		507,572
Balance at end of period at Jan. 30, 2016	4,140,123	$ 1,015	3,028,921	(795)	1,110,982
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued pursuant to stock options and awards (in shares)		11,203
Shares issued pursuant to stock options and awards	57,531	$ 22	57,509
Issuance of common stock under the employee stock purchase plan (in shares)		2,276
Issuance of common stock under the employee stock purchase plan	16,688	$ 5	16,683
Cancellation of restricted stock units for net share settlement (in shares)		(1,653)
Cancellation of restricted stock units for net share settlement	(16,682)	$ (3)	(16,679)
Share-based compensation	113,402		113,402
Tax benefit (deficiency) from employee stock transactions	$ (24)		(24)
Repurchase of common stock (in shares)	(13,300)	(13,303)
Repurchase of common stock	$ (183,064)	$ (27)	(183,037)
Cash dividends declared and paid (cumulatively $0.24 per share)	(122,292)				(122,292)
Net income (loss)	21,151				21,151
Other comprehensive income (loss)	818			818
Balance (in shares) at Jan. 28, 2017		506,095
Balance at end of period at Jan. 28, 2017	$ 4,027,651	$ 1,012	$ 3,016,775	$ 23	$ 1,009,841

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Statement of Stockholders' Equity [Abstract]
Cash dividends declared (in usd per share)	$ 0.24	$ 0.24	$ 0.24
Cash dividends paid (in usd per share)	$ 0.24	$ 0.24	$ 0.24

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ 21,151	$ (811,400)	$ 435,346
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	107,851	100,176	106,248
Share-based compensation	113,970	133,779	137,246
Amortization and write-off of acquired intangible assets	10,641	12,688	18,337
Restructuring and other related charges	52,581	16,032	17
Loss (gain) from investments in privately-held companies	0	3,503	(8,829)
Amortization (accretion) of premium /discount on available-for-sale securities	3,319	8,112	(3,582)
Other non-cash expense (income), net	(3,312)	2,196	1,765
Excess tax benefits from share-based compensation	(37)	(26)	(145)
Deferred income tax	44,637	6,096	(12,913)
Changes in assets and liabilities, net of assets acquired and liabilities assumed in acquisitions:
Accounts receivable	(12,084)	97,655	34,165
Inventories	29,325	90,586	39,454
Prepaid expenses and other assets	1,825	(23,209)	5,788
Accounts payable	(28,153)	(105,898)	(43,871)
Accrued liabilities and other non-current liabilities	3,763	(15,202)	(30,024)
Carnegie Mellon University accrued litigation settlement	(736,000)	736,000	0
Accrued employee compensation	18,016	(33,338)	43,561
Deferred income	14,072	(12,398)	6,373
Net cash provided by (used in) operating activities	(358,435)	205,352	728,936
Cash flows from investing activities:
Purchases of available-for-sale securities	(489,856)	(1,056,045)	(1,128,319)
Sales of available-for-sale securities	616,697	991,657	534,908
Maturities of available-for-sale securities	239,557	311,843	291,402
Distributions from (investments in) privately-held companies	16	(41)	(701)
Purchases of time deposits	(275,000)	0	0
Maturities of time deposits	125,000	0	0
Proceeds from sale of an investment in a privately-held company	0	0	13,220
Purchases of technology licenses	(10,309)	(8,236)	(16,424)
Purchases of property and equipment	(44,510)	(37,255)	(63,030)
Purchases of equipment previously leased	0	(10,240)	0
Proceeds from equipment held for sale	0	10,007	0
Net cash provided by (used in) investing activities	161,595	201,690	(368,944)
Cash flows from financing activities:
Repurchase of common stock	(181,564)	(260,875)	(64,962)
Proceeds from employee stock plans	74,219	80,717	112,357
Minimum tax withholding paid on behalf of employees for net share settlement	(16,683)	(24,358)	(26,494)
Dividend payments to shareholders	(122,292)	(122,821)	(122,801)
Payments on technology license obligations	(20,965)	(12,528)	(13,010)
Excess tax benefits from share-based compensation	37	26	145
Net cash used in financing activities	(267,248)	(339,839)	(114,765)
Net increase (decrease) in cash and cash equivalents	(464,088)	67,203	245,227
Cash and cash equivalents at beginning of the year	1,278,180	1,210,977	965,750
Cash and cash equivalents at end of the year	$ 814,092	$ 1,278,180	$ 1,210,977

The Company and its Significant Accounting Policies

12 Months Ended

Jan. 28, 2017

Accounting Policies [Abstract]

The Company and its Significant Accounting Policies

The Company

Marvell Technology Group Ltd., a Bermuda exempted company, and its subsidiaries (the “Company”), is a fabless semiconductor provider of high-performance application-specific standard products. The Company’s core strength is the development of complex System-on-a-Chip devices, leveraging its extensive technology portfolio of intellectual property in the areas of analog, mixed-signal, digital signal processing, and embedded and standalone integrated circuits. The Company also develops platforms that it defines as integrated hardware along with software that incorporates digital computing technologies designed and configured to provide an optimized computing solution. The Company’s broad product portfolio includes devices for storage, networking and connectivity.

Basis of Presentation

The Company’s fiscal year is the 52- or 53-week period ending on the Saturday closest to January 31. Accordingly, every fifth or sixth fiscal year will have a 53-week period. The additional week in a 53-week year is added to the fourth quarter, making such quarter consist of 14 weeks. Fiscal 2017, 2016 and 2015 each had a 52-week period. The next 53-week year will be fiscal 2018.

Discontinued Operations

In connection with the plan the Company announced in November 2016 to restructure its operations to refocus its research and development, increase operational efficiency and improve profitability, it also planned to divest certain businesses and it began an active program to locate buyers for several businesses. As of January 28, 2017, two of these businesses have been classified as discontinued operations (see "Note 2 - Discontinued Operations"). As required, the Company has retrospectively recast its consolidated statements of operations and balance sheets for all periods presented to reflect these businesses as discontinued operations. The cash flows of these discontinued operations were not material for any period presented and we have not segregated the cash flows of these businesses in the consolidated statements of cash flows. Management was also required to make certain assumptions and apply judgment to determine historical expenses related to the discontinued operations presented in prior periods. Unless noted otherwise, discussion in the Notes to Consolidated Financial Statements refers to the Company’s continuing operations.

Use of Estimates

The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States ("GAAP") requires management to make estimates, judgments and assumptions that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingent liabilities. On an ongoing basis, the Company evaluates its estimates, including those related to performance-based compensation, revenue recognition, provisions for sales returns and allowances, inventory excess and obsolescence, investment fair values, goodwill and other intangible assets, restructuring, income taxes, litigation and other contingencies. In addition, the Company uses assumptions when employing the Monte Carlo simulation and Black-Scholes valuation models to calculate the fair value of share-based awards that are granted. Actual results could differ from these estimates, and such differences could affect the results of operations reported in future periods.

Principles of Consolidation

The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated. The functional currency of the Company and its subsidiaries is the U.S. dollar.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less from the date of purchase to be cash equivalents. Cash and cash equivalents consist of cash on deposit with banks, time deposits, U.S. government and agency debt, municipal debt securities, corporate debt securities and money market funds.

Investments

The Company’s marketable investments are classified as available-for-sale and are reported at fair value. The Company determines any realized gains or losses on the sale of available-for-sale securities on a specific identification method, and such gains and losses are recorded as a component of interest and other income, net. Unrealized gains and losses of the available-for-sale securities are excluded from earnings and reported as a component of accumulated other comprehensive income. Time deposits with maturities greater than 90 days, but less than one year are classified in short-term investments as held-to-maturity since the Company has both the intent and ability to hold them to maturity.

In general, investments with original maturities of greater than 90 days and remaining maturities of less than one year are classified as short-term investments. Investments with maturities beyond one year may also be classified as short-term based on their highly liquid nature and can be sold to fund current operations.

The Company also has equity investments in privately-held companies. If the Company has the ability to exercise significant influence over the investee, but not control, or if the investee is a partnership type investment, the Company accounts for the investments under the equity method. If the Company does not have the ability to exercise significant influence over the operations of the investee, the Company accounts for the investment under the cost method. Investments in privately-held companies are included in other non-current assets.

Impairment of Investments

The Company performs a periodic review of its available-for-sale securities to determine whether an other-than-temporary impairment has occurred. Generally, for an individual security that has been in an unrealized loss position for an extended period of time, the Company evaluates whether an impairment charge should be recognized. Its evaluation is based on specific facts and circumstances at the time of assessment, including general market conditions, and the duration and extent to which the fair value is below cost. If the fair value of a debt security is less than its amortized cost, then an other-than-temporary impairment for the difference is recognized if:


•	the Company has the intent to sell the security;


•	it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost base; or


•	a credit loss exists insofar as the Company does not expect to recover the entire recognized amortized cost of the security.

If a debt security’s market value is below amortized cost and the Company either intends to sell the security or it is more likely than not that the Company will be required to sell the security before its anticipated recovery, the Company records an other-than-temporary impairment charge to interest and other income, net in the consolidated statements of operations.

Investments in privately-held companies are subject to a periodic impairment review. Investments are considered impaired when the fair value is below the investment’s cost basis and the decline in value is judged to be other-than-temporary. This assessment is based on a qualitative and quantitative analysis, including, but not limited to, the investee’s revenue and earnings trends, available cash and liquidity, and the status of the investee’s products and the related market for such products.

Derivative Financial Instruments

The Company accounts for its derivative instruments as either assets or liabilities and carries them at fair value. For derivative instruments that hedge the exposure to variability in expected future cash flows and are designated as cash flow hedges, the effective portion of the gain or loss on the derivative instrument is reported as a component of accumulated other comprehensive income in the consolidated statements of shareholders’ equity and reclassified into earnings in the same period or periods during which the hedged transaction affects earnings. The ineffective portion of the gain or loss on the derivative instrument is recognized in current earnings. To receive hedge accounting treatment, cash flow hedges must be highly effective in offsetting changes to expected future cash flows on hedged transactions. Derivatives that are not designated as hedges must be adjusted to fair value through earnings.

Concentration of Credit Risk and Significant Customers

Financial instruments that potentially subject the Company to a significant concentration of credit risk consist principally of cash equivalents, short-term investments and accounts receivable. Cash, cash equivalents and short-term investments balances are maintained with high-quality financial institutions, the composition and maturities of which are regularly monitored by management. The Company believes that the concentration of credit risk in its trade receivables, which consists of a customer base located primarily in the Asia Pacific Region, is substantially mitigated by the Company’s credit evaluation process, relatively short collection terms and the high level of credit worthiness of its customers. The Company performs ongoing credit evaluations of its customers’ financial conditions and limits the amount of credit extended when deemed necessary based upon payment history and the customer’s current credit worthiness, but generally requires no collateral. The Company regularly reviews the allowance for bad debt and doubtful accounts by considering factors such as historical experience, credit quality, age of the accounts receivable balances and current economic conditions that may affect a customer’s ability to pay.

The Company’s accounts receivable was concentrated with three customers at January 28, 2017, who represented 14%, 13%, and 11% of gross accounts receivable, respectively, compared with two customers at January 30, 2016, who represented 13% and 11% of gross accounts receivable, respectively.

Historically, a relatively small number of customers have accounted for a significant portion of our net revenue. Net revenue attributable to significant customers whose revenues as a percentage of net revenue was 10% or greater of total net revenues is presented in the following table:



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Customer:
Western Digital*	21	%	19	%	20	%
Toshiba	13	%	**%		**%
Seagate	9	%	14	%	13	%
Wintech	10	%	**%		11	%

* The percentage of net revenues reported for Western Digital for fiscal year 2017 includes net revenue of HGST and SanDisk that became subsidiaries of Western Digital in late fiscal 2016.
** Less than 10% of net revenue

The Company continuously monitors the creditworthiness of its distributors and believes these distributors’ sales to diverse end customers and to diverse geographies further serve to mitigate the Company’s exposure to credit risk.

Inventories

Inventory is stated at the lower of cost or market, cost being determined under the first-in, first-out method. The total carrying value of the Company’s inventory is reduced for any difference between cost and estimated market value of inventory that is determined to be excess, obsolete or unsellable inventory based upon assumptions about future demand and market conditions. If actual future demand for the Company’s products is less than currently forecasted, the Company may be required to write inventory down below the current carrying value. Once the carrying value of inventory is reduced, it is maintained until the product to which it relates to is sold or otherwise disposed of. Inventoriable shipping and handling costs are classified as a component of cost of goods sold in the consolidated statements of operations.

Property and Equipment, Net

Property and equipment, net, are stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets, which ranges from 3 to 7 years for machinery and equipment, and 3 to 4 years for computer software, and furniture and fixtures. Buildings are depreciated over an estimated useful life of 30 years and building improvements are depreciated over estimated useful lives of 15 years. Leasehold improvements are depreciated over the shorter of the remaining lease term or the estimated useful life of the asset.

Goodwill

Goodwill is recorded when the consideration paid for a business acquisition exceeds the fair value of net tangible and intangible assets acquired. Goodwill is measured and tested for impairment annually on the last business day of the fiscal fourth quarter and whenever events or changes in circumstances indicate the carrying amount of goodwill may not be recoverable. The Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount.

If the Company concludes that it is more likely than not that the fair value of a reporting unit is less than its carrying amount or if the Company notes multiple qualitative factors indicating potential impairment, then a two-step quantitative impairment test is performed. The first step requires comparing the fair value of the reporting unit to its net book value, including goodwill. The Company has identified that its business operates as a single operating segment with two components (Storage, and Networking & Connectivity), which it has concluded can be aggregated into a single reporting unit for purposes of testing goodwill impairment. As part of a restructuring announced in November 2016 (see “Note 8 - Restructuring and Other Related Charges”), the former Smart Networked Devices and Solutions component was renamed to Networking & Connectivity. A potential impairment exists if the fair value of the reporting unit is lower than its net book value. The second step of the process is only performed if a potential impairment exists, and it involves determining the implied fair value of the reporting unit’s goodwill and comparing it to the carrying value of goodwill. If the carrying value of goodwill were to exceed its implied fair value, then the Company would record an impairment loss for the difference in the fiscal quarter in which the determination is made.

Long-Lived Assets and Intangible Assets

The Company assesses the impairment of long-lived assets and intangible assets whenever events or changes in circumstances indicate that the carrying amount of long-lived assets may not be recoverable. The Company estimates the future cash flows, undiscounted and without interest charges, expected to be generated by the assets from its use or eventual disposition. If the sum of the expected undiscounted future cash flows is less than the carrying amount of those assets, the Company recognizes an impairment loss based on the excess of the carrying amount over the fair value of the assets. Please see “Note 7 — Goodwill and Acquired Intangible Assets, Net” for further details regarding impairment of acquisition-related identified intangible assets.

Acquisition-related identified intangible assets are amortized on a straight-line basis over their estimated economic lives. In-process research and development (“IPR&D”) is not amortized until the completion of the related development.

Foreign Currency Transactions

The functional currency of all of the Company’s non-U.S. operations is the U.S. dollar. Monetary accounts maintained in currencies other than the U.S. dollar are re-measured using the foreign exchange rate at the balance sheet date. Operational accounts and nonmonetary balance sheet accounts are measured and recorded at the exchange rate in effect at the date of the transaction. The effects of foreign currency re-measurement are reported in current operations.

Revenue Recognition

The Company recognizes revenue when there is persuasive evidence of an arrangement, delivery has occurred, the fee is fixed or determinable, and collection is reasonably assured. If the Company grants extended payment terms greater than its standard terms for a customer such that collectability is not assured, the revenue is deferred upon shipment and will be recognized when the payment becomes due provided all other revenue recognition criteria have been satisfied.

Product revenue is generally recognized upon shipment of product to customers, net of accruals for estimated sales returns and rebates. However, some of the Company’s sales are made through distributors under agreements allowing for price protection and limited rights of stock rotation on products unsold by the distributors. Although title passes to the distributor upon shipment, terms and payment by the Company’s distributors is not contingent on resale of the product. Product revenue on sales made through distributors with price protection and stock rotation rights are deferred until the distributors sell the product to end customers. Deferred revenue less the related cost of the inventories is reported as deferred income. The Company does not believe that there is any significant exposure related to impairment of deferred cost of sales, as its historical returns have been minimal and inventory turnover for its distributors generally ranges from 60 to 90 days. The Company’s sales to direct customers are made primarily pursuant to standard purchase orders for delivery of products.

A portion of the Company’s net revenue is derived from sales through third-party logistics providers, who maintain warehouses in close proximity to the customer’s facilities. Revenue from sales through these third-party logistics providers is not recognized until the product is pulled from stock by the end customer.

The provision for estimated sales returns on product sales is recorded in the same period the related revenues are recorded. These estimates are based on historical returns, analysis of credit memo data and other known factors. Actual returns could differ from these estimates. The Company accounts for rebates by recording reductions to revenue for rebates in the same period that the related revenue is recorded. The amount of these reductions is based upon the terms agreed to with the customer.

Advertising Expense

Advertising costs are expensed as incurred. The Company recorded $0.5 million, $5.1 million and $5.6 million of advertising costs for fiscal 2017, 2016 and 2015, respectively, included in selling and marketing expenses in the consolidated statement of operations.

Share-Based Compensation

Share-based compensation is measured at the grant date, based on the fair value of the award, and is recognized as expense over the requisite service period. The Company amortizes share-based compensation expense for time-based awards under the straight-line attribution method over the vesting period. Share-based compensation expense for performance-based awards is recognized when it becomes probable that the performance conditions will be met. Once it becomes probable that a performance-based award will vest, the Company recognizes compensation expense equal to the number of shares expected to vest multiplied by the fair value of the award at the grant date, which is amortized using the accelerated method. In the case of performance-based awards based on total shareholder return (“TSR”), share-based compensation expense is amortized over the requisite service period. For stock purchase rights under the stock purchase plan, the Company amortizes share-based compensation expense ratably over the two-year offering period.

The Company estimates the fair value of time-based stock option and stock purchase awards on the date of grant using the Black Scholes option-pricing model. The fair value of TSR awards is estimated on the date of grant using a Monte Carlo simulation model since the award is indexed to the price of the Company’s common stock as set forth under the terms of the award. The value of the portion of the awards that is ultimately expected to vest is recognized as expense over the requisite service periods. The Black Scholes and Monte Carlo models incorporate various highly subjective assumptions including expected term of awards, expected future stock price volatility, expected dividend yield and risk-free interest rate.

In developing estimates used to calculate assumptions, the Company establishes the expected term for employee stock options, as well as expected forfeiture rates, based on the historical settlement experience and after giving consideration to vesting schedules. Assumptions for stock option exercises and pre-vesting terminations of stock options are stratified by two employee groups and one employee/non-employee group with sufficiently distinct behavior patterns. Expected volatility was developed based on equally weighted combination of historical stock price volatility and implied volatility derived from traded options on the Company’s stock in the marketplace. The expected dividend yield is calculated by dividing annualized dividend payments by the closing stock price on the grant date of the option.

The fair value of each restricted stock unit is estimated based on the market price of the Company’s common shares on the date of grant less the expected dividend yield.

Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from initial estimates. Share-based compensation expense for time-based and performance-based awards is recorded net of estimated forfeitures such that expense is recorded only for those share-based awards that are expected to vest. Previously recognized expense is reversed for the portion of awards forfeited prior to vesting as and when forfeitures occurred.

Comprehensive Income (Loss)

Comprehensive income (loss) is comprised of net income and unrealized gains and losses, net of tax, on available-for-sale securities, auction rate securities and cash flow hedges. Accumulated other comprehensive income (loss), as presented on the accompanying consolidated balance sheets, consists of net unrealized gains and losses on available-for-sale securities, auction rate securities and cash flow hedges, net of tax.

Accounting for Income Taxes

The Company recognizes income taxes using an asset and liability approach. This approach requires the recognition of taxes payable or refundable for the current year, and deferred tax liabilities and assets for the future tax consequences of events that have been recognized in the Company’s consolidated financial statements or tax returns. The measurement of current and deferred taxes is based on provisions of the enacted tax law and the effects of future changes in tax laws or rates are not anticipated.

Using available evidence and judgment, the Company establishes a valuation allowance for deferred tax assets, when it is determined that it is more likely than not that they will not be realized. Valuation allowances have been provided primarily against the U.S. research and development credits. Valuation allowances have also been provided against certain acquired operating losses and the deferred tax assets of foreign subsidiaries. A change in the assessment of the realization of deferred tax assets may materially impact the Company’s tax provision in the period in which a change of assessment occurs.

The Company is subject to income tax audits by the respective tax authorities in each jurisdiction in which the Company operates. The Company recognizes the effect of income tax positions only if these positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is more than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company records interest and penalties related to unrecognized tax benefits in income tax expense.

Warranty

The Company’s products are generally subject to warranty, which provides for the estimated future costs of repair or replacement upon shipment of the product. The Company’s products carry a standard 90-day warranty, with certain exceptions in which the warranty period can extend to more than one year based on contractual agreements. The warranty accrual is primarily estimated based on historical claims compared to historical revenues and assumes that the Company will have to replace products subject to a claim. From time to time, the Company becomes aware of specific warranty situations, and it records specific accruals to cover these exposures. Warranty expenses were not material in fiscal 2017, 2016 and 2015.

Recent Accounting Pronouncements

Accounting Pronouncements Recently Adopted

In April 2015, the Financial Accounting Standards Board ("FASB") issued new guidance to help entities evaluate the accounting for fees paid by a customer in a cloud computing arrangement, which the Company adopted beginning in the first quarter of fiscal 2017. The guidance provides a basis for evaluating whether a cloud computing arrangement includes a software license and whether the license arrangement should be accounted for as an intangible asset. This guidance also strikes from previous authoritative guidance, the use by analogy to the accounting for capital leases, which the Company previously applied in the accounting for certain of its technology license agreements. As such, the Company accounts for new agreements under the new guidance by determining if capitalization as an asset is appropriate or if the arrangement should be treated as a subscription with expense recognized in the period when service is received. Similarly, the Company will re-evaluate the accounting for any renewals to existing license agreements in accordance with the new guidance as they occur.

Accounting Pronouncements Not Yet Effective

In May 2014, the FASB issued a new standard on the recognition of revenue from contracts with customers, which will supersede nearly all existing revenue recognition guidance under GAAP. The new standard will require an entity to recognize revenue from the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The guidance addresses, in particular, contracts with more than one performance obligation, as well as the accounting for some costs to obtain or fulfill a contract with a customer, and provides for additional disclosures with respect to revenues and cash flows arising from contracts with customers. Public entities are required to apply the amendments on either a full or modified retrospective basis for annual periods beginning after December 15, 2017 and for interim periods within those annual periods. This update will be effective for the Company beginning in the first quarter of fiscal year 2019. Early adoption is not permitted. The Company plans to adopt the standard retrospectively with the cumulative effect of initially applying it recognized at the date of initial application under the full retrospective approach.

The Company’s initial assessment has identified a change in revenue recognition timing on our component sales made to distributors. The Company expects to recognize revenue when the Company delivers to the distributor rather than deferring recognition until the distributor sells the components. Other changes may be identified as the Company completes the assessment phase of its revenue project. On the date of initial application, the Company will remove the deferred net revenue on component sales made to distributors through a cumulative adjustment to retained earnings. The Company expects the revenue and corresponding cost of goods sold deferral to be offset by the acceleration of revenue recognition as control of the product transfers to our customer.

To date, the Company has completed the assessment phase of its revenue project and has begun the next phase for the design and development of its systems and processes to enable compliance with the new standards. It expects to complete this phase in its second quarter of fiscal 2018 ending July 29, 2017. Currently, the Company has determined to apply the amendments on a full retrospective basis, although it may decide to change at a later date. The Company will continue to track relevant elements and finalize its evaluation of any changes to its accounting policies and disclosures.

In July 2015, the FASB issued an amendment to its guidance regarding the subsequent measurement of inventory. Currently, inventory is measured at the lower of cost or market. Market could be replacement cost, net realizable value or net realizable value less an approximately normal profit margin. Under this amended guidance, inventory is to be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. This amendment applies to inventories for which cost is determined by methods other than last-in first-out and the retail inventory method. This standard is effective for annual and interim reporting periods beginning after December 15, 2016. The Company does not expect the adoption of this new accounting standard in the first quarter of fiscal 2018 will have a material effect on its consolidated financial statements.

In February 2016, the FASB issued a new standard on the accounting for leases, which requires a lessee to record a right-of-use asset and a corresponding lease liability on the balance sheet for all leases with terms longer than twelve months. The standard also expands the required quantitative and qualitative disclosures surrounding lease arrangements. The standard is effective for annual and interim reporting periods beginning after December 15, 2018. The Company is currently evaluating the effect this new guidance will have on its consolidated financial statements.

In March 2016, the FASB issued new guidance which simplifies several aspects of the accounting for share-based payment award transactions, including the accounting for income taxes, forfeitures and statutory tax withholding requirements, as well as classification in the statement of cash flows. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016. The Company does not expect the adoption of this new accounting standard to have a material effect on its consolidated financial statements since the Company will continue to account for forfeitures based on an estimated forfeiture rate.

In June 2016, the FASB issued a new standard requiring financial assets measured at amortized cost be presented at the net amount expected to be collected, through an allowance for credit losses that is deducted from the amortized cost basis. The standard eliminates the probable initial recognition in current GAAP and reflects an entity’s current estimate of all expected credit losses. The measurement of expected credit losses is based upon historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the financial assets. The standard is effective for annual and interim reporting periods beginning after December 15, 2019. The Company is currently evaluating the effect this new guidance will have on its consolidated financial statements.

In August 2016, the FASB issued an accounting standards update to add or clarify guidance on the classification of certain cash receipts and cash payments in the statement of cash flows. The amendments in the update provide guidance on eight specific cash flow issues, and is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. The amendments to the guidance should be applied using a retrospective transition method for each period presented and if it is impracticable to apply all of the amendments retrospectively for some of the issues, the amendments for those issues would be applied prospectively as of the earliest date practicable. The Company is evaluating the effect this new guidance will have on its consolidated statement of cash flows.

In October 2016, the FASB issued new guidance which simplifies the accounting for the income tax effects of intra-entity transfers and will require companies to recognize the income tax effects of intra-entity transfers of assets other than inventory when the transfer occurs. Previous guidance required companies to defer the income tax effects of intra-entity transfers of assets until the asset had been sold to an outside party or otherwise recognized. The guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. The Company is evaluating the effect this new guidance will have on its consolidated financial statements.

In November 2016, the FASB issued new guidance which requires entities to include in their cash and cash-equivalent balances in the statement of cash flows those amounts that are deemed to be restricted cash and restricted cash equivalents. As a result, companies will no longer present transfers between cash and cash equivalents, and restricted cash and restricted cash equivalents in the statement of cash flows. The guidance is effective for annual and interim periods beginning after December 15, 2017. Early adoption is permitted, including adoption in an interim period. The Company is evaluating the effect this new guidance will have on its consolidated financial statements.

In January 2017, the FASB issued an accounting standards update which revises the definition of a business. The amendments provide a more robust framework for determining when a set of assets and activities is a business and is intended to help companies evaluate whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. The guidance is effective for annual and interim periods beginning after December 15, 2018. Early adoption is permitted for certain transactions as specifically described in the guidance. The Company is evaluating the effect this new guidance will have on its consolidated financial statements.

In January 2017, the FASB issued an accounting standards update which simplifies the accounting for goodwill impairment by eliminating Step 2 of the goodwill impairment test, which required a hypothetical purchase price allocation. Instead, an entity shall perform its annual or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. Goodwill impairment will now be measured as the amount by which a reporting unit’s carrying value exceeds its fair value, but not in an amount to exceed the carrying amount of goodwill allocated to the reporting unit. This guidance will be effective for annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019, with early adoption permitted for interim or annual goodwill impairment tests performed on testing dates after January 31, 2017. The Company’s current year step one test outcomes indicated that the adoption of this pronouncement is not expected to have a material effect on the Company’s consolidated financial statements.

Discontinued Operations

12 Months Ended

Jan. 28, 2017

Discontinued Operations and Disposal Groups [Abstract]

Discontinued Operations

In July 2016, the Company hired a new President and Chief Executive Officer who immediately initiated a review of the Company’s businesses in order to assess the market position and potential returns of each business. The outcome of this process was to align the Company’s core competencies to ensure it is investing in areas that are most likely to provide the best long-term returns. The Company identified several businesses that it believes no longer fit with its core competencies and long-term goals to focus on the storage, networking and connectivity markets.

After the business review had been completed, the Company assessed its overall resource requirements in terms of direct costs and indirect costs. In November 2016, the Company announced a plan to restructure its operations to refocus its research and development, increase operational efficiency and improve profitability. The Company expects that the restructuring actions, which include discontinuing investment in specific research and development programs, streamlining engineering processes, and consolidating research and development sites, will eliminate approximately 900 positions worldwide. In addition, the Company plans to divest certain businesses with approximately $60 million in operating expenses and $100 million in revenue based on a first half of fiscal 2017 annualized run rate.

As part of the above actions, the Company began an active program to locate buyers for several businesses. The Company concluded that the divestitures of these businesses represented a strategic shift that has a major effect on the Company’s operations and financial results. These businesses were deemed not to align with the Company’s core business. As of January 28, 2017, the Company believes two of these businesses will be sold within the next twelve months. The Company has entered into an agreement with a buyer for one of the businesses and is actively seeking a buyer for another business, which it believes is probable and, therefore, the Company expects the sale of these two businesses to be completed within the next twelve months. The Company continues its effort to sell a third business. However, at this time, management does not believe the sale will be completed within the next twelve months. As a result, the Company has classified the two above-mentioned businesses as discontinued operations, and has reclassified its statement of operations and balance sheets for all periods presented in its consolidated financial statements to report the effect of these discontinued operations.

The following table presents a reconciliation of the carrying amounts of major classes of assets and liabilities of the discontinued operations to the total assets and liabilities of the disposal group classified as held for sale that are presented separately in the consolidated balance sheets (in thousands):



	January 28, 2017		January 30, 2016
Current assets held for sale:
Inventory	$	8,154	$	9,059
Property and equipment, net	2,898		2,762
Goodwill	26,532		26,532
Acquired intangible assets, net	3,799		6,063
Other	1,490		679
Current assets held for sale for discontinued operations	42,873		45,095
Other assets held for sale
Property and equipment, net	2,973		—
Total assets of the disposal group classified as held for sale	$	45,846	$	45,095
Current liabilities held for sale:
Deferred Income	$	1,670	$	1,749
Total liabilities of the disposal group classified as held for sale	$	1,670	$	1,749

The following table presents a reconciliation of the major financial lines constituting the results of operations for discontinued operations to the net loss from discontinued operations presented separately in the consolidated statement of operations (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Net Revenue	$	98,755		$	76,612		$	69,757
Operating costs and expenses:
Cost of goods sold	60,799			52,219			44,281
Research and development	53,784			59,524			67,263
Selling and marketing	4,750			4,684			4,325
General and administrative	963			769			795
Amortization of acquired intangible assets	325			650			650
Total operating costs and expenses	120,621			117,846			117,314
Loss from discontinued operations before income taxes	(21,866		)	(41,234		)	(47,557		)
Provision for income taxes	977			1,011			884
Net loss from discontinued operations	$	(22,843	)	$	(42,245	)	$	(48,441	)

The Company has elected not to separately report discontinued operations in its consolidated statement of cash flows since its effect is not material. Non-cash operating amounts reported for discontinued operations include share-based compensation expense of $9.2 million, $7.8 million and $6.2 million in fiscal 2017, 2016 and 2015, respectively. Depreciation, amortization and capital expenditures are not material and there were no other material non-cash investing amounts related to the cash flows from discontinued operations. Due to the Company's transfer pricing arrangements, the Company generates income in most jurisdictions in which it operates, regardless if there is a loss on a consolidated basis. As such, the Company has reflected tax expense of $1.0 million, $1.0 million, and $0.9 million for fiscal years 2017, 2016, and 2015, respectively, attributable to discontinued operations.

- Definition

The entire disclosure related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721665-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5C
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721675-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=64862545&loc=SL51724579-110230

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721663-107760

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721659-107760

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5A
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721671-107760

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5D
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721677-107760

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1474-107760

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760

+ Details

Investments

12 Months Ended

Jan. 28, 2017

Investments, Debt and Equity Securities [Abstract]

Investments

The following tables summarize the Company’s investments (in thousands):



	January 28, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Short-term investments:
Available-for-sale:
Corporate debt securities	$	432,603	$	281	$	(776	)	$	432,108
U.S. government and agency debt	185,584		86		(283		)	185,387
Asset backed securities	45,541		33		(47		)	45,527
Foreign government and agency debt	13,425		—		(50		)	13,375
Municipal debt securities	27,916		4		(49		)	27,871
Held-to-Maturity:
Time deposits	150,000		—		—			150,000
Total short-term investments	855,069		404		(1,205		)	854,268
Long-term investments:
Available-for-sale:
Auction rate securities	4,615		—		—			4,615
Total long-term investments	4,615		—		—			4,615
Total investments	$	859,684	$	404	$	(1,205	)	$	858,883



	January 30, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Short-term investments:
Available-for-sale:
Corporate debt securities	$	558,337	$	766	$	(1,282	)	$	557,821
U.S. government and agency debt	317,595		64		(254		)	317,405
Asset backed securities	76,711		81		(56		)	76,736
Foreign government and agency debt	21,370		2		(14		)	21,358
Municipal debt securities	31,211		45		(7		)	31,249
Total short-term investments	1,005,224		958		(1,613		)	1,004,569
Long-term investments:
Available-for-sale:
Auction rate securities	11,296		—		—			11,296
Total long-term investments	11,296		—		—			11,296
Total investments	$	1,016,520	$	958	$	(1,613	)	$	1,015,865

As of January 28, 2017, the Company’s investment portfolio included auction rate securities with an aggregate par value of $5 million. Although these auction rate securities have continued to pay interest and the underlying collateral has not deteriorated, there is currently limited trading volume. The Company uses a discounted cash flow model to estimate the fair value of the auction rate securities based on its estimated timing and amount of future interest and principal payments. The fair value of the auction rate securities as of January 28, 2017 was $0.4 million less than the par value and is included in long-term investments.

The Company made a determination in January 2016 that it did not expect to recover the par value of these auction rate securities and considers any impairment of these securities to be other-than-temporary. There has been no change in circumstances since January 2016 based upon the current time horizon for holding these auction rate securities and the continuation of an illiquid market. Based on the Company's assessment of fair value as of January 28, 2017, the Company determined there was no further impairment of these auction rate securities.

During fiscal 2017, the Company sold auction rate securities with an aggregate par value of $7.5 million for total net proceeds of $6.9 million. The carrying value of these auction rate securities was $6.7 million and resulted in a net gain of $0.2 million recorded in interest and other income, net, in the year ended January 28, 2017.

Gross realized gains and gross realized losses on sales of available-for-sale securities are presented in the following table (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Gross realized gains	$	2,047		$	1,654		$	1,618
Gross realized losses	(547		)	(1,923		)	(169		)
Impairment loss	—			(1,204		)	—
Total net realized gains (losses)	$	1,500		$	(1,473	)	$	1,449

The contractual maturities of available-for-sale securities are presented in the following table (in thousands):



	January 28, 2017				January 30, 2016
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in one year or less	$	423,151	$	423,058	$	304,117	$	304,035
Due between one and five years	423,669		422,995		689,847		689,279
Due over five years	12,864		12,830		22,556		22,551
	$	859,684	$	858,883	$	1,016,520	$	1,015,865

For individual securities that have been in a continuous unrealized loss position, the fair value and gross unrealized loss for these securities aggregated by investment category and length of time in an unrealized position are presented in the following tables (in thousands):



	January 28, 2017
	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
Corporate debt securities	$	199,382	$	(751	)	$	16,063	$	(25	)	$	215,445	$	(776	)
U.S. government and agency debt	94,064		(283		)	—		—			94,064		(283		)
Asset backed securities	16,754		(47		)	—		—			16,754		(47		)
Foreign government and agency debt	11,875		(48		)	1,499		(2		)	13,374		(50		)
Municipal debt securities	17,450		(47		)	1,248		(2		)	18,698		(49		)
Total securities	$	339,525	$	(1,176	)	$	18,810	$	(29	)	$	358,335	$	(1,205	)



	January 30, 2016
	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
Corporate debt securities	$	283,138	$	(1,237	)	$	14,383	$	(45	)	$	297,521	$	(1,282	)
U.S. government and agency debt	263,325		(254		)	—		—			263,325		(254		)
Asset backed securities	46,646		(56		)	—		—			46,646		(56		)
Foreign government and agency debt	16,458		(14		)	—		—			16,458		(14		)
Municipal debt securities	2,943		(5		)	1,571		(2		)	4,514		(7		)
Total securities	$	612,510	$	(1,566	)	$	15,954	$	(47	)	$	628,464	$	(1,613	)

- Definition

The entire disclosure for investments in certain debt and equity securities.

+ References + Details

Supplemental Financial Information

12 Months Ended

Jan. 28, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Supplemental Financial Information

Supplemental Financial Information (in thousands)

Consolidated Balance Sheets



	January 28, 2017		January 30, 2016
Cash and cash equivalents:
Cash	$	651,953	$	669,312
Cash equivalents:
Time deposits	67,000		209,405
U.S. government and agency debt	17,497		184,374
Money market funds	36,122		160,400
Corporate debt securities	31,280		54,689
Municipal debt securities	8,740		—
Foreign government and agency debt	1,500		—
Cash and cash equivalents	$	814,092	$	1,278,180



	January 28, 2017		January 30, 2016
Provision for sales returns and allowances:
Sales returns	$	470	$	1,873
Doubtful accounts	914		889
	$	1,384	$	2,762



	January 28, 2017		January 30, 2016
Inventories:
Work-in-process	$	110,083	$	125,800
Finished goods	61,886		75,158
Inventories	$	171,969	$	200,958

Inventory held by third-party logistics providers is recorded as consigned inventory on the Company’s consolidated balance sheet. The amount of inventory held at third-party logistics providers was $26.5 million and $21.0 million at January 28, 2017 and January 30, 2016, respectively.



	January 28, 2017			January 30, 2016
Property and equipment, net:
Machinery and equipment	$	578,248		$	575,954
Buildings and building improvements	194,290			194,247
Computer software	99,186			102,840
Land	53,373			53,373
Leasehold improvements	49,004			50,192
Furniture and fixtures	23,903			27,118
Construction in progress	11,240			1,353
	1,009,244			1,005,077
Less: Accumulated depreciation	(765,847		)	(708,299		)
Property and equipment, net	$	243,397		$	296,778

The Company recorded depreciation expense of $82.4 million, $73.8 million and $78.3 million for fiscal 2017, 2016 and 2015, respectively.



	January 28, 2017		January 30, 2016
Other non-current assets:
Technology and other licenses	$	53,254	$	48,091
Deferred tax assets	26,608		34,505
Investments in privately-held companies	5,787		5,804
Prepaid land use rights	12,810		13,123
Deposits	3,756		51,512
Other	11,109		10,996
Other non-current assets	$	113,324	$	164,031

Amortization of technology and other licenses was $25.5 million, $26.4 million and $27.9 million in fiscal 2017, 2016 and 2015, respectively. In connection with its restructuring plan announced in November 2016, the Company recorded the impairment of a $45.0 million nonrefundable deposit due to non-utilization of the related contract in fiscal 2017.



	January 28, 2017		January 30, 2016
Accrued liabilities:
Accrued rebates	$	26,095	$	41,320
Restructuring liability	23,150		3,842
Accrued royalties	17,349		16,217
Technology license obligations	21,905		17,985
Accrued legal expense	5,127		9,761
Other	49,865		42,935
Accrued liabilities	$	143,491	$	132,060



	January 28, 2017			January 30, 2016
Deferred income:
Net deferred revenue	$	93,148		$	75,541
Deferred cost of goods sold	(25,024		)	(21,568		)
Deferred income	$	68,124		$	53,973



	January 28, 2017		January 30, 2016
Other non-current liabilities:
Technology license obligations	$	14,949	$	12,461
Long-term accrued employee compensation	4,075		6,078
Deferred tax liabilities	38,777		1,098
Other	6,136		7,326
Other non-current liabilities	$	63,937	$	26,963

Accumulated other comprehensive income (loss):

The changes in accumulated other comprehensive income (loss) by components are presented in the following tables (in thousands):



	Unrealized Gain (Loss) on Marketable Securities			Unrealized Loss on Auction Rate Securities			Unrealized Gain (Loss) on Cash Flow Hedges			Total
Balance at January 31, 2015	$	3,768		$	(2,274	)	$	(1,186	)	$	308
Other comprehensive income (loss) before reclassifications	(3,838		)	—			1,111			(2,727		)
Amounts reclassified from accumulated other comprehensive income (loss)	(586		)	2,274			(64		)	1,624
Net current-period other comprehensive income (loss), net of tax	(4,424		)	2,274			1,047			(1,103		)
Balance at January 30, 2016	(656		)	—			(139		)	(795		)
Other comprehensive income before reclassifications	1,766			—			1,496			3,262
Amounts reclassified from accumulated other comprehensive income	(1,911		)	—			(533		)	(2,444		)
Net current-period other comprehensive income (loss), net of tax	(145		)	—			963			818
Balance at January 28, 2017	$	(801	)	$	—		$	824		$	23

The amounts reclassified from accumulated other comprehensive income (loss) by components are presented in the following table (in thousands):



	Year Ended
Affected Line Item in the Statement of Operations	January 28, 2017		January 30, 2016			January 31, 2015
Interest and other income, net:
Available-for-sale securities:
Marketable securities	$	1,911	$	586		$	1,245
Auction rate securities	—		(2,274		)	(512		)
Operating costs and expenses:
Cash flow hedges:
Research and development	467		48			(198		)
Selling and marketing	10		(1		)	(8		)
General and administrative	56		17			(12		)
Total	$	2,444	$	(1,624	)	$	515

Consolidated Statements of Operations



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Interest and other income, net:
Interest income	$	13,198		$	15,982		$	11,370
Net realized gain (loss) on investments	1,500			(1,473		)	1,449
Currency translation gain	1,746			6,655			1,871
Other income (loss)	946			(2,773		)	9,811
Interest expense	(368		)	(706		)	(1,167		)
	$	17,022		$	17,685		$	23,334

Consolidated Statements of Cash Flows



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Supplemental cash flow information:
Cash paid for interest	$	363	$	703	$	1,167
Cash paid for income taxes, net	$	17,032	$	13,363	$	15,727
Non-Cash Investing and Financing Activities:
Purchase of intellectual property under license obligations	$	27,081	$	13,800	$	—
Unsettled trade receivable of available-for-sale securities	$	7,742	$	53,749	$	—
Unsettled trade payable of available-for-sale securities	$	15,371	$	—	$	—
Unpaid purchase of property and equipment at end of year	$	2,547	$	9,069	$	7,083
Unpaid repurchases of our common shares	$	1,499	$	—	$	—

Net income (loss) per share

The Company reports both basic net income (loss) per share, which is based on the weighted average number of common shares outstanding during the period, and diluted net income (loss) per share, which is based on the weighted average number of common shares outstanding and potentially dilutive shares outstanding during the period. The computations of basic and diluted net income (loss) per share are presented in the following table (in thousands, except per share amounts):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Numerator:
Income (loss) from continuing operations	$	43,994		$	(769,155	)	$	483,787
Loss from discontinued operations	(22,843		)	(42,245		)	(48,441		)
Net income (loss)	$	21,151		$	(811,400	)	$	435,346
Denominator:
Weighted average shares — basic	509,738			510,945			511,089
Effect of dilutive securities:
Share-based awards	7,775			—			9,671
Weighted average shares — diluted	517,513			510,945			520,760
Income (loss) from continuing operations per share:
Basic	$	0.09		$	(1.51	)	$	0.95
Diluted	$	0.09		$	(1.51	)	$	0.93
Loss from discontinued operations per share:
Basic	$	(0.05	)	$	(0.08	)	$	(0.10	)
Diluted	$	(0.05	)	$	(0.08	)	$	(0.09	)
Net income (loss) per share:
Basic	$	0.04		$	(1.59	)	$	0.85
Diluted	$	0.04		$	(1.59	)	$	0.84

Potential dilutive securities include dilutive common shares from share-based awards attributable to the assumed exercise of stock options, restricted stock units and employee stock purchase plan shares using the treasury stock method. Under the treasury stock method, potential common shares outstanding are not included in the computation of diluted net income per share, if their effect is anti-dilutive.

Anti-dilutive potential shares are presented in the following table (in thousands):



	Year Ended
	January 28, 2017	January 30, 2016	January 31, 2015
Weighted average shares outstanding:
Share-based awards	22,642	64,420	35,636

Anti-dilutive potential shares from share-based awards are excluded from the calculation of diluted earnings per share for all periods reported above because either their exercise price exceeded the average market price during the period or the share-based awards were determined to be anti-dilutive based on applying the treasury stock method. Anti-dilutive potential shares from share-based awards are also excluded from the calculation of diluted earnings per share for the year ended January 30, 2016 due to the net loss reported in fiscal 2016.

Derivative Financial Instruments

12 Months Ended

Jan. 28, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Financial Instruments

The Company manages some of its foreign currency exchange rate risk through the purchase of foreign currency exchange contracts that hedge against the short-term effect of currency fluctuations. The Company’s policy is to enter into foreign currency forward contracts with maturities less than 12 months that mitigate the effect of rate fluctuations on certain local currency denominated operating expenses. All derivative instruments are recorded at fair value in either prepaid expenses and other current assets or accrued liabilities. The Company reports cash flows from derivative instruments in cash flows from operating activities. The Company uses quoted prices to value its derivative instruments.

The notional amounts of outstanding forward contracts were as follows (in thousands):



	Buy Contracts
	January 28, 2017		January 30, 2016
Israeli shekel	$	63,523	$	19,082

Cash Flow Hedges. The Company designates and documents its foreign currency forward exchange contracts as cash flow hedges for certain operating expenses. The Company evaluates and calculates the effectiveness of each hedge at least quarterly. The effective change is recorded in accumulated other comprehensive income and is subsequently reclassified to operating expense when the hedged expense is recognized. Ineffectiveness is recorded in interest and other income, net.

Other Foreign Currency Forward Contracts. The Company may enter into foreign currency forward exchange contracts to hedge certain assets and liabilities denominated in various foreign currencies that it does not designate as hedges for accounting purposes. The maturities of these contracts are generally less than 12 months. Gains or losses arising from the remeasurement of these contracts to fair value each period are recorded in interest and other income, net.

The fair value of foreign currency exchange contracts was not significant as of any period presented.

The following table provides information about gains (losses) associated with our derivative financial instruments (in thousands):



	Location of Gains (Losses) in Statement of Operations	Amount of Gains (Losses) in Statement of Operations for the Year Ended
	Location of Gains (Losses) in Statement of Operations	January 28, 2017		January 30, 2016			January 31, 2015
Derivatives designated as cash flow hedges:
Forward contracts:	Research and development	$	737	$	(390	)	$	(1,930	)
	Selling and marketing	15		(5		)	(24		)
	General and administrative	86		(26		)	(157		)
		$	838	$	(421	)	$	(2,111	)

The portion of gains (losses) excluded from the assessment of hedge effectiveness are included in interest and other income, net, and these amounts were $(0.3) million, $(0.1) million and $0.2 million in fiscal 2017, 2016 and 2015, respectively. In addition, realized losses from forward contracts that are not designated as hedging instruments that are included in interest and other income, net, were not material in fiscal 2017, 2016 and 2015. The Company also reports hedge ineffectiveness from derivative financial instruments in current earnings, which were not material in fiscal 2017, 2016 and 2015. No cash flow hedges were terminated as a result of forecasted transactions that did not occur.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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-Paragraph 1
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 2
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
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-Paragraph 5
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Paragraph 4H
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5708775-113959

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5708773-113959

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 16: http://www.xbrl.org/2003/role/presentationRef
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Reference 17: http://www.xbrl.org/2003/role/presentationRef
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Reference 18: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41638-113959

Reference 19: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Fair Value Measurements

12 Months Ended

Jan. 28, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair value is an exit price representing the amount that would be received in the sale of an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier value hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value:

Level 1 — Observable inputs that reflect quoted prices for identical assets or liabilities in active markets.

Level 2 — Other inputs that are directly or indirectly observable in the marketplace.

Level 3 — Unobservable inputs that are supported by little or no market activity.

The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value.

The Company’s Level 1 assets include institutional money-market funds that are classified as cash equivalents and marketable investments in U.S. government and agency debt, which are valued primarily using quoted market prices. The Company’s Level 2 assets include its marketable investments in time deposits, corporate debt securities, foreign government and agency debt, municipal debt securities and asset backed securities as the market inputs used to value these instruments consist of market yields, reported trades and broker/dealer quotes, which are corroborated with observable market data. In addition, forward contracts, and the severance pay fund are classified as Level 2 assets as the valuation inputs are based on quoted prices and market observable data of similar instruments. The Company’s investments in auction rate securities are classified as Level 3 assets because there are currently no active markets for the auction rate securities and consequently the Company is unable to obtain independent valuations from market sources. Therefore, the auction rate securities are valued using a discounted cash flow model. Some of the inputs to the discounted cash flow model are unobservable in the market.

The tables below set forth, by level, the Company’s assets and liabilities that are measured at fair value on a recurring basis. The tables do not include assets and liabilities that are measured at historical cost or any basis other than fair value (in thousands):



	Fair Value Measurements at January 28, 2017
	Level 1		Level 2		Level 3		Total
Items measured at fair value on a recurring basis:
Assets
Cash equivalents:
Money market funds	$	36,122	$	—	$	—	$	36,122
Time deposits	—		67,000		—		67,000
U.S. government and agency debt	17,497		—		—		17,497
Corporate debt securities	—		31,280		—		31,280
Foreign government and agency debt	—		1,500		—		1,500
Municipal debt securities	—		8,740		—		8,740
Short-term investments:
U.S. government and agency debt	185,387		—		—		185,387
Corporate debt securities	—		432,108		—		432,108
Asset backed securities	—		45,527		—		45,527
Foreign government and agency debt	—		13,375		—		13,375
Municipal debt securities	—		27,871		—		27,871
Time deposits	—		150,000		—		150,000
Prepaid expenses and other current assets:
Foreign currency forward contracts	—		735		—		735
Long-term investments:
Auction rate securities	—		—		4,615		4,615
Other non-current assets:
Severance pay fund	—		736		—		736
Total assets	$	239,006	$	778,872	$	4,615	$	1,022,493
Liabilities
Accrued liabilities:
Foreign currency forward contracts	$	—	$	58	$	—	$	58



	Fair Value Measurements at January 30, 2016
	Level 1		Level 2		Level 3		Total
Items measured at fair value on a recurring basis:
Assets
Cash equivalents:
Money market funds	$	160,400	$	—	$	—	$	160,400
Time deposits	—		209,405		—		209,405
U.S. government and agency debt	184,374		—		—		184,374
Corporate debt securities	—		54,689		—		54,689
Short-term investments:
U.S. government and agency debt	317,405		—		—		317,405
Corporate debt securities	—		557,821		—		557,821
Asset backed securities	—		76,736		—		76,736
Foreign government and agency debt	—		21,358		—		21,358
Municipal debt securities	—		31,249		—		31,249
Prepaid expenses and other current assets:
Foreign currency forward contracts	—		30		—		30
Long-term investments:
Auction rate securities	—		—		11,296		11,296
Other non-current assets:
Severance pay fund	—		678		—		678
Total assets	$	662,179	$	951,966	$	11,296	$	1,625,441
Liabilities
Accrued liabilities:
Foreign currency forward contracts	$	—	$	195	$	—	$	195

The following table summarizes the change in fair values for Level 3 assets for the years ended January 28, 2017 and January 30, 2016 (in thousands):



	Level 3
Changes in fair value during the year (pre-tax):
Balance at January 31, 2015	$	10,226
Impairment loss	(1,204		)
Unrealized gain included in accumulated other comprehensive income	2,274
Balance at January 30, 2016	11,296
Sales, redemption and settlement	(6,681		)
Unrealized gain included in accumulated other comprehensive income	—
Balance at January 28, 2017	$	4,615

There were no transfers of assets between levels in either fiscal 2017 or 2016.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Goodwill and Acquired Intangible Assets, Net

12 Months Ended

Jan. 28, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Acquired Intangible Assets, Net

Goodwill

There was no activity for acquisitions or divestitures recorded to goodwill in fiscal 2017 and 2016 due to business combinations.

The Company has identified that its business operates as a single operating segment with two components that it has concluded can be aggregated into a single reporting unit. In connection with the restructuring plan the Company announced in November 2016 (see “Note 8 - Restructuring and Other Related Charges”), its Board of Directors approved a plan to sell certain businesses that are classified and reported in the consolidated statement of operations as discontinued operations. As a result, goodwill was allocated to these businesses based on relative fair value since each represents a portion of the Company’s reporting unit (see "Note 2 - Discontinued Operations"). The Company obtained an independent valuation to determine the fair value of these businesses for purposes of allocating the goodwill and to complete an assessment for goodwill impairment of the Company’s continuing operations. Although the Company engaged an independent valuation specialist to provide the fair value calculations, management assumed full responsibility for the valuation results, and the accuracy and completeness of the underlying financial data and corresponding assumptions. The Company’s annual test for goodwill impairment as of the last day of the fourth quarter of fiscal 2017 did not result in any impairment charge.

Acquired Intangible Assets, Net

The carrying amounts of acquired intangible assets are as follows (in thousands):



		January 28, 2017							January 30, 2016
	Range of Useful Lives	Gross Carrying Amounts		Accumulated Amortization and Write-Offs			Net Carrying Amounts		Gross Carrying Amounts		Accumulated Amortization and Write-Offs			Net Carrying Amounts
Purchased and core technology	4 - 8 years	$	25,798	$	(22,227	)	$	3,571	$	25,798	$	(17,950	)	$	7,848
Customer intangibles	5 - 7 years	24,700		(24,700		)	—		24,700		(20,601		)	4,099
Total acquired intangible assets from continuing operations, net		$	50,498	$	(46,927	)	$	3,571	$	50,498	$	(38,551	)	$	11,947

Intangible assets, along with the related accumulated amortization, are removed from the table above at the end of the fiscal year they become fully amortized. The Company recorded charges of $3.4 million to write off IPR&D in fiscal 2015 upon the Company’s decision to discontinue the related project. These impairment charges are included in amortization and write-off of acquired intangible assets in the consolidated statements of operations.

Based on the identified intangible assets recorded at January 28, 2017, the future amortization expense of identified intangibles for the next five fiscal years is as follows (in thousands):



Fiscal Year
2018	$	3,571
2019 and thereafter	—
	$	3,571

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Restructuring and Other Related Charges

12 Months Ended

Jan. 28, 2017

Restructuring and Related Activities [Abstract]

Restructuring and Other Related Charges

The following table provides a summary of restructuring and other related charges as presented in the Consolidated Statements of Operations (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Cost of goods sold	$	—	$	10,292	$	—
Restructuring and other related charges	105,186		53,251		10,438
Write-off of acquired intangible assets	—		—		3,386
	$	105,186	$	63,543	$	13,824

The following table presents details of charges recorded by the Company related to the restructuring actions described below (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016		January 31, 2015
Severance and related costs	$	41,035		$	43,926	$	5,181
Facilities and related costs	6,587			1,407		1,924
Loss on early contract termination	—			1,644		3,230
Other exit-related costs	5,452			534		86
	53,074			47,511		10,421
Release of reserves:
Severance	(86		)	—		—
Other exit-related costs	(383		)	—		—

Impairment and write-off of assets:
Prepaid deposit	45,000			—		—
Inventory	—			8,046		—
Technology licenses	629			1,250		—
Equipment and other	6,952			6,736		17
Acquired intangible asset	—			—		3,386
	$	105,186		$	63,543	$	13,824

Fiscal 2017. The Company recorded $105.2 million of restructuring and other related charges in fiscal 2017 as described in the following paragraphs:

In November 2016, the Company announced a plan to restructure its operations to refocus its research and development, increase operational efficiency and improve profitability (see "Note 2 - Discontinued Operations"). The Company expects that the restructuring actions, which include discontinuing investment in specific research and development programs, streamlining engineering processes, and consolidating research and development sites, will eliminate approximately 900 positions worldwide. In addition, the Company plans to divest certain businesses (see “Note 3 - Discontinued Operations”). These actions began immediately following the announcement and are expected to be fully executed by the end of October 2017. As a result of these actions, the Company expects to incur charges of $90 million to $110 million through fiscal 2017, including cash charges of $35 million to $50 million. Restructuring and restructuring-related charges include an estimate of severance, asset impairment, lease termination fees and other costs.

The Company recorded restructuring and other related charges of $98.7 million in fiscal 2017 related to this restructuring plan announced in November 2016. The charges included $41.0 million of severance benefits, $5.5 million of other exit-related costs primarily related to contract cancellation penalties, $1.9 million of costs related to closing certain facilities, $45.0 million to fully impair a nonrefundable deposit due to the non-utilization of the related contract, and $5.4 million for the impairment of equipment and technology licenses. The Company is on track to complete activities related to this restructuring plan and expects to incur additional charges in fiscal 2018 since facilities related to the closure of certain operations have yet to be vacated and certain additional actions related to this restructuring plan have yet to occur. Estimated remaining costs are expected to be approximately $10 million to $15 million, which is in line with the Company's original estimated amount.

In connection with the restructuring of its mobile platform business in September 2015, substantially all of the remaining activities expected to be completed in the first half of fiscal 2017 were completed. As a result, the Company recorded a charge of $1.9 million in fiscal 2017, which included $2.2 million primarily for the write off of all remaining mobile-related equipment that was previously classified as held for sale that was offset by a net credit of $0.3 million, mainly due to the release of a reserve related to the loss on contract termination previously recognized in fiscal 2016. Total cumulative charges recorded through the end of fiscal 2017 related to this restructuring action were $46.4 million, which included $28.1 million of severance benefits, a $1.3 million loss on early contract termination, $8.8 million for impairment of technology licenses and certain equipment, $0.2 million related to facility closures and an $8.0 million write down of inventory. The total cumulative charges were lower than the original estimate of $100 million to $130 million primarily due to the Company’s decision to retain approximately 140 mobile employees to support the remaining mobile business than it originally anticipated and certain equipment planned for disposal was subsequently determined to have alternative use. The Company also offered retention bonuses to another 128 mobile employees to remain through the ramp down of certain operations. Their benefit packages were recognized ratably over the employees’ remaining service periods through the first half of fiscal 2017.

In addition to the restructuring actions described in the preceding paragraph, the Company recorded charges of $4.6 million in the fiscal 2017, primarily for the remaining lease obligation, net of sublease income, upon vacating certain floors in one of its Israel facilities and ongoing operating expenses of vacated facilities related to restructuring actions in previous years.

Fiscal 2016. The Company recorded $63.5 million of restructuring and other related charges in fiscal 2016 as described in the following paragraphs.

In September 2015, the Company announced a significant restructuring of its mobile platform business in order to focus the mobile product line on more profitable opportunities and align its expenses with corporate targets. The Company implemented actions to significantly downsize the mobile platform organization to refocus its technology to other emerging opportunities. As a result of these actions, the Company recorded restructuring and other related charges of $44.4 million in fiscal 2016 related to this restructuring. The charge primarily included severance benefits for 825 employees who were notified of their termination, a loss on early contract termination, the impairment of technology licenses and certain equipment, and the write down of inventory. Substantially all of the affected employees departed by the end of fiscal 2016.

In May 2015, the Company decided to further reduce its research and development operations in Israel and close certain other design centers, primarily located in Europe and the U.S. in connection with its ongoing effort to streamline its business. As a result, the Company recorded a total $16.3 million charge in fiscal 2016 comprised of $15.1 million for severance related to the termination of 358 employees who were notified of their termination and $1.2 million for a lease obligation related to a facility that the Company vacated in July 2015. Substantially all of the activities associated with these actions were completed and all affected employees departed before the end of fiscal 2016.

In March 2015, the Company exercised the early buyout option under an existing operating lease for corporate equipment that it planned to sell as part of a cost reduction action. The Company actively sought a buyer and classified the equipment as held for sale within prepaid and current assets on the consolidated balance sheet. It also ceased depreciation on the asset and recorded impairment charges of $1.4 million through the second quarter ended August 1, 2015. In October 2015, the Company sold the corporate equipment for net proceeds of $9.3 million, which approximated the carrying value and resulted in no gain or loss recognized upon the sale of the asset.

In addition to the restructuring actions described in the preceding paragraphs, the Company recorded $1.4 million of additional charges primarily associated with ongoing operating expenses of vacated facilities related to restructuring actions in previous fiscal years and maintenance costs for the corporate equipment sold in October 2015.

Fiscal 2015. The Company decided to streamline its operations, primarily in Israel, to align with its overall strategic plan, and to discontinue the development of a product it originally acquired in a business combination. As a result, the Company recorded $13.8 million of restructuring and other related charges in fiscal 2015. Facilities and related costs primarily included a charge for a portion of the lease obligation related to vacating the floors the Company no longer planned to occupy in one of its Israel facilities. The write-off of an acquired intangible asset in fiscal 2015 was due to the Company’s decision to discontinue the related project. These actions were substantially completed by the end of fiscal 2015. In addition, the Company decided to exercise an early buy out option to acquire an asset under an existing operating lease agreement, and recorded a $3.2 million loss from the termination of the agreement in fiscal 2015.

The following table sets forth a reconciliation of the beginning and ending restructuring liability balances by each major type of costs associated with the restructuring charges (in thousands):



	November 2016 Restructuring									Mobile & Other Prior Restructuring
	Severance and related costs			Facilities and related costs			Other exit-related costs			Severance and related costs			Facilities and related costs			Other exit-related costs			Total
Balance at January 31, 2015	$	—		$	—		$	—		$	—		$	1,339		$	3,230		$	4,569
Cost reduction charges	—			—			—			43,926			1,407			2,178			47,511
Cash payments	—			—			—			(42,741		)	(1,567		)	(3,764		)	(48,072		)
Exchange rate adjustment	—			—			—			(30		)	(106		)	—			(136		)
Balance at January 30, 2016	—			—			—			1,155			1,043			1,644			3,842
Cost reduction charges	41,020			1,872			5,452			15			4,715			—			53,074
Cash payments	(24,065		)	(110		)	(829		)	(1,082		)	(5,112		)	(1,261		)	(32,459		)
Release of reserves	—			—			—			(86		)	—			(383		)	(469		)
Exchange rate adjustment	45			1			2			(2		)	65			—			111
Balance at January 28, 2017	17,000			1,763			4,625			—			711			—			24,099
Less: non-current portion	—			(949		)	—			—			—			—			(949		)
Current portion	$	17,000		$	814		$	4,625		$	—		$	711		$	—		$	23,150

During fiscal 2017, the Company paid severance and related benefit costs to approximately 500 employees who departed in fiscal 2017 as part of the restructuring actions described above. The remaining severance represents termination benefits determined to have been established under a substantive ongoing benefit arrangement for which payment was considered probable due to the timing of notification to certain additional employee groups after the end of fiscal 2017 and is expected to be paid within the first half of fiscal 2018. The balance at January 28, 2017 for facility and related costs includes remaining payments under lease obligations related to vacated space that are expected to be paid through fiscal 2019. Other exit-related costs are expected to be paid in the first quarter of fiscal 2018.

Income Taxes

12 Months Ended

Jan. 28, 2017

Income Tax Disclosure [Abstract]

Income Taxes

The U.S. and non-U.S. components of income (loss) before income taxes of continuing operations consist of the following (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016			January 31, 2015
U.S. operations	$	30,889	$	32,433		$	30,607
Non-U.S. operations	86,127		(790,253		)	449,103
	$	117,016	$	(757,820	)	$	479,710

The provision (benefit) for income taxes consists of the following (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Current income tax provision (benefit):
Federal	$	8,289		$	10,482		$	8,826
State	180			83			(161		)
Foreign	19,916			(5,326		)	171
Total current income tax provision (benefit)	28,385			5,239			8,836
Deferred income tax provision (benefit):
Federal	(5,062		)	(4,355		)	(1,775		)
State	(12		)	580			16
Foreign	49,711			9,871			(11,154		)
Total deferred income tax provision (benefit)	44,637			6,096			(12,913		)
Total provision (benefit) for income taxes	$	73,022		$	11,335		$	(4,077	)

Deferred tax assets consist of the following (in thousands):



	January 28, 2017			January 30, 2016
Deferred tax assets:
Federal and California research and other tax credits	$	450,503		$	414,662
Reserves and accruals	35,887			35,200
Share-based compensation	3,733			4,476
Net operating losses	5,361			11,055
Gross deferred tax assets	495,484			465,393
Valuation allowance	(456,541		)	(424,914		)
Total deferred tax assets	38,943			40,479
Total deferred tax liabilities	(51,112		)	(7,073		)
Net deferred tax assets (liabilities)	$	(12,169	)	$	33,406

As presented in the consolidated balance sheets as of January 28, 2017 and January 30, 2016, and in the table above, unrecognized tax benefits have been offset by deferred tax assets for certain net operating losses that are available to be used in the amount of $7.5 million and $6.3 million, respectively.

At the end of fiscal 2017, the Company recorded a valuation allowance of $456.5 million which is an increase of $31.6 million from fiscal 2016. The Company provided a full valuation allowance against its federal and various state research credits which it earns in excess of its current year tax liabilities, as well as a portion against its net operating loss carryforwards in the U.S. federal and California jurisdictions. Based on the objectively verifiable positive and negative evidence, the Company determined that it is more likely than not that these research credits and net operating losses will not be realized in the future. The Company also provided a valuation allowance against the deferred tax assets of a portion of its operations in Israel, which has cumulative losses in recent years and is not projecting sufficient future taxable income to realize the benefit of its deferred tax assets.

As of January 28, 2017, the Company had net operating loss carryforwards available to offset future taxable income of approximately $82.7 million, $1.4 million and $6.3 million for foreign, U.S. federal and state of California purposes, respectively. The federal carryforwards will expire in various fiscal years between 2022 and 2028, and the California carryforwards will expire at various fiscal years between 2018 and 2033, if not utilized before these years. The majority of the Company’s non-U.S. losses carry forward indefinitely. For U.S. federal income tax return purposes, the Company had research tax credit carryforwards of approximately $268.5 million that expire through fiscal 2037. As of January 28, 2017, the Company had unused California research and tax credit carryforwards of approximately $279.4 million, which can be carried forward indefinitely. Included in the U.S. federal and California carryforward amounts are $63.0 million and $60.0 million, respectively, that are attributable to excess tax benefits from stock options. Upon realization, the benefit associated with these credits will increase additional paid-in capital. The Company also has research and investment tax credit carryforwards of approximately $24.3 million in other U.S. states that expire through fiscal 2032 due to the statutes of limitation.

The Company consists of a Bermuda parent holding company with various foreign and U.S. subsidiaries. The applicable statutory rate in Bermuda is zero for the Company for fiscal 2017, 2016, and 2015. For purposes of the reconciliation between the provision (benefit) for income taxes at the statutory rate and the effective tax rate, a notional U.S. 35% rate is applied as follows:



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Provision at U.S. notional statutory rate	35.0	%	35.0	%	35.0	%
Difference in U.S. and non-U.S. tax rates	(23.7	)	(37.1	)	(35.1	)
Benefits from utilization of general business credits	(35.8	)	5.2		(10.8	)
Change in valuation allowance	30.6		(4.3	)	9.5
Withholding taxes	42.8		—		—
Tax effects of global restructuring	14.3		—		—
Other	(0.8	)	(0.3	)	0.5
Effective tax rate	62.4	%	(1.5	)%	(0.9	)%

The following table reflects changes in the unrecognized tax benefits (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Unrecognized tax benefits as of the beginning of the period	$	29,139		$	45,197		$	51,682
Increases related to prior year tax positions	2,080			304			976
Decreases related to prior year tax positions	—			(4,334		)	(386		)
Increases related to current year tax positions	2,363			4,237			5,356
Settlements	—			(704		)	—
Lapse in the statute of limitations	(6,576		)	(9,739		)	(10,691		)
Foreign exchange gain	(3,213		)	(5,822		)	(1,740		)
Gross amounts of unrecognized tax benefits as of the end of the period	$	23,793		$	29,139		$	45,197

Included in the balances as of January 28, 2017 is $23.4 million of unrecognized tax benefit that would affect the effective income tax rate if recognized. Also, $7.5 million and $6.3 million of the gross unrecognized tax benefits presented in the table above are offset against deferred tax assets in the consolidated balance sheets as of January 28, 2017 and January 30, 2016, respectively.

The amounts in the table above do not include the related interest and penalties. The amount of interest and penalties accrued was approximately $21.6 million as of January 28, 2017, $26.4 million as of January 30, 2016, and $27.7 million as of January 31, 2015. The Company’s policy is to recognize these interest and penalties as a component of income tax expense. The consolidated statements of operations for fiscal 2017, 2016, and 2015 included $2.7 million, $4.6 million, and $3.8 million, respectively, of interest and penalties related to the unrecognized tax benefits.

The Company is subject to income tax audits by the respective tax authorities in all of the jurisdictions in which it operates. The examination of tax liabilities in each of these jurisdictions requires the interpretation and application of complex and sometimes uncertain tax laws and regulations. As of January 28, 2017, the material jurisdictions that are subject to examination include China, Israel, Singapore, Switzerland and the United States for the Company’s fiscal years 2006 through 2016. As of January 28, 2017, several of the Company’s non-U.S. entities are under examination for fiscal years encompassing 2006 through 2016. The Company is also under examination by the State of California for fiscal year 2013 and 2014.

For fiscal 2018, the Company will continue to review its tax positions and provide for or reverse unrecognized tax benefits as issues arise. During the next 12 months, it is reasonably possible that the amount of unrecognized tax benefits could increase or decrease significantly due to changes in tax law in various jurisdictions, new tax audits and changes in the U.S. dollar as compared to foreign currencies within the next 12 months. Excluding these factors, uncertain tax positions may decrease by as much as $9.5 million from the lapse of the statutes of limitation in various jurisdictions during the next 12 months.

The Singapore Economic Development Board (“EDB”) initially granted a 10-year Pioneer Status in July 1999 to the Company’s Singapore subsidiary. In October 2004, the Company’s subsidiary in Singapore was granted a second incentive known as the Develop and Expansion Incentive (“DEI”), and in June 2006, the EDB agreed to extend the Pioneer status for 15 years to June 2014. The Company re-negotiated with the Singapore government and in fiscal 2015, they extended the DEI tax credits to the Company until June 2019. In order to retain these tax benefits in Singapore, the Company must meet certain operating conditions relating to, among other things, maintenance of a regional headquarters function, and research and development activities in Singapore. In fiscal 2017, 2016 and 2015 tax savings associated with these tax holidays were approximately $0.9 million, $5.3 million and $0.1 million, respectively, which if paid would impact the Company’s earnings per share by $0.01 per share in fiscal 2016, and less than $0.01 per share in fiscal 2017 and 2015.

Under the Israeli Encouragement law of “approved or benefited enterprise,” two branches of Marvell Israel (M.I.S.L) Ltd., the GTL branch and the cellular branch (formerly Marvell DSPC), are entitled to approved and benefited tax programs that include reduced tax rates and exemption of certain income, subject to various operating and other conditions. Income from the approved or benefited enterprises, with the exception of capital gains, is eligible up to fiscal 2027. There was no such benefit in fiscal 2017, 2016 and 2015.

During fiscal 2007, each of the Swiss Federal Department of Economy and the Vaud Cantonal Tax Administration granted the Company’s subsidiary in Switzerland a 10 year tax holiday on revenues from research and design wafer supply trading activities, which commenced in February 2007 and expired at the end of fiscal 2016. The fiscal 2016, and 2015 tax savings associated with this tax holiday was approximately $3.7 million and $4.5 million, respectively, which provided earnings per share of $0.01 per share in fiscal 2016 and 2015. No tax savings was recognized in fiscal 2017 due to expiration of the tax holiday.

As a result of restructuring actions taken in the fourth quarter of fiscal 2017, the Company recognized tax expense of $66.9 million, $50.1 million of this amount was attributable to foreign withholding taxes on undistributed earnings of certain subsidiaries that are no longer considered to be indefinitely reinvested. $16.8 million is attributable to foreign taxes associated with such restructuring actions.

The Company’s principal source of liquidity as of January 28, 2017 consisted of approximately $1.7 billion of cash, cash equivalents and short-term investments, of which approximately $970 million was held by foreign subsidiaries (outside Bermuda). Approximately $620 million of this amount held by foreign subsidiaries is related to undistributed earnings which have been indefinitely reinvested outside of Bermuda. These funds are primarily held in China, Israel and the United States. We have plans to use such amounts to fund various activities outside of Bermuda, including working capital requirements, capital expenditures for expansion, funding of future acquisitions or other financing activities. If such funds were needed by the parent company in Bermuda or if the amounts were otherwise no longer considered indefinitely reinvested, we would incur a tax expense of approximately $190 million.

Commitments and Contingencies

12 Months Ended

Jan. 28, 2017

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Warranty Obligations

The Company’s products carry a standard 90-day warranty with certain exceptions in which the warranty period can extend to more than one year based on contractual agreements. The Company’s warranty expense has not been significant in the periods presented.

Lease Commitments

The Company leases some of its facilities, equipment and computer aided design software under non-cancelable operating leases. Rent expense, net of sublease income for fiscal 2017, 2016, and 2015 was approximately $23.7 million, $23.8 million and $26.1 million, respectively. The Company also purchases certain intellectual property under technology license obligations. Future minimum lease payments, net of estimated sublease income, and payments under technology license obligations as of January 28, 2017, are presented in the following tables (in thousands):



Fiscal Year	Minimum Operating Leases Payments
2018	$	37,167
2019	27,004
2020	16,708
2021	3,767
2022	610
Thereafter	2,147
Total future minimum lease payments	$	87,403



Fiscal Year	Technology License Obligations
2018	$	23,180
2019	7,025
2020 and thereafter	7,025
Total future minimum lease payments	$	37,230
Less: amount representing interest	(170		)
Present value of future minimum payments	37,060
Less: current portion	(22,111		)
Non-current portion	$	14,949

Technology license obligations include the liabilities under agreements for technology licenses between the Company and various vendors.

Purchase Commitments

Under the Company’s manufacturing relationships with its foundry partners, cancellation of all outstanding purchase orders is allowed but requires payment of all costs and expenses incurred through the date of cancellation. As of January 28, 2017, these foundries had incurred approximately $208.8 million of manufacturing costs and expenses relating to the Company’s outstanding purchase orders.

Intellectual Property Indemnification

The Company has agreed to indemnify certain customers for claims made against the Company’s products where such claims allege infringement of third-party intellectual property rights, including, but not limited to, patents, registered trademarks, and/or copyrights. Under the aforementioned indemnification clauses, the Company may be obligated to defend the customer and pay for the damages awarded against the customer as well as the attorneys’ fees and costs under an infringement claim. The Company’s indemnification obligations generally do not expire after termination or expiration of the agreement containing the indemnification obligation. Generally, there are limits on and exceptions to the Company’s potential liability for indemnification. Although historically the Company has not made significant payments under these indemnification obligations, the Company cannot estimate the amount of potential future payments, if any, that it might be required to make as a result of these agreements. The maximum potential amount of any future payments that the Company could be required to make under these indemnification obligations could be significant.

Contingencies

The Company and certain of its subsidiaries are currently parties to various legal proceedings, including those noted in this section. The legal proceedings and claims described below could result in substantial costs and could divert the attention and resources of the Company’s management. The Company is also engaged in other legal proceedings and claims not described below, which arise in the ordinary course of its business. The Company is currently unable to predict the final outcome of these lawsuits and therefore cannot determine the likelihood of loss or estimate a range of possible loss, except with respect to amounts where it has determined a loss is both probable and estimable and has made an accrual. Litigation is subject to inherent uncertainties and unfavorable rulings could occur. An unfavorable ruling in litigation, particularly patent litigation, could require the Company to pay damages, one-time license fees or ongoing royalty payments, and could prevent the Company from manufacturing or selling some of its products or limit or restrict the type of work that employees involved in such litigation may perform for the Company, any of which could adversely affect financial results in future periods. There can be no assurance that these matters will be resolved in a manner that is not adverse to the Company’s business, financial condition, results of operations or cash flows.

Carnegie Mellon University Litigation. On March 6, 2009, CMU filed a complaint in the U.S. District Court for the Western District of Pennsylvania (“W.D. of Pennsylvania”). CMU has asserted U.S. Patent Nos. 6,201,839 and 6,438,180 (collectively, the “CMU patents in suit”), which relate to read-channel integrated circuit devices and the hard disk drive (“HDD”) incorporating such devices. A jury trial began on November 26, 2012. On December 26, 2012, a jury delivered a verdict that found the CMU patents in suit were literally and willfully infringed and valid, and awarded past damages in the amount of $1.17 billion. Based on post-trial motions and decisions, the W.D. of Pennsylvania calculated the damages including enhancement to total approximately $1.54 billion, and held that, under its decision, CMU is entitled to post judgment interest and an ongoing royalty. On May 7, 2014, the W.D. of Pennsylvania entered final judgment, from which the Company filed a notice of appeal on May 14, 2014. On August 4, 2015, the Federal Circuit in a three-judge panel issued an opinion affirming in part, reversing in part, and vacating and remanding in part. On February 16, 2016, the Company and CMU entered into a Settlement Agreement and Patent License pursuant to which the Company has agreed to pay an aggregate of $750 million, without any ongoing royalty payments, to CMU and the parties have agreed to mutually acceptable release, license and covenant not to sue provisions. Please see “Note 15 — Carnegie Mellon University Settlement” for additional information on the effect of the settlement in the Company’s consolidated financial statements for fiscal 2017. In connection with the settlement, the primary supersedeas bond that the Company entered into in connection with this litigation was reduced to $439 million and the secondary bond, which is secured, was adjusted to $311 million. All of the Company’s obligations under both bonds were discharged pursuant to an order releasing supersedeas bonds on April 21, 2016. On October 18, 2016, the case was dismissed with prejudice.

Innovatio Litigation. On March 16, 2015, Innovatio IP Ventures, LLC filed suit against MSI in the U.S. District Court for the Northern District of Illinois, alleging infringement of U.S. Patent Nos. 6,697,415; 5,844,893; 5,740,366; 7,916,747; 6,665,536; 7,013,138; 7,107,052; 5,546,397; 7,710,907; 7,710,935; 6,714,559; 7,457,646; and 6,374,311, purportedly related to certain wireless technology. The complaint sought unspecified damages. On October 11, 2016, the case was dismissed with prejudice.

Luna Litigation and Consolidated Cases. On September 11, 2015, Daniel Luna filed an action asserting putative class action claims on behalf of the Company’s shareholders in the United States District Court for the Southern District of New York (“S.D. of New York”). This action was consolidated with two additional, nearly identical complaints subsequently filed by Philip Limbacher and Jim Farno. The complaints asserted violations of federal securities laws based on allegations that the Company and certain of its officers and directors (Sehat Sutardja, Michael Rashkin, and Sukhi Nagesh) made, caused to be made, or failed to correct false and/or misleading statements in the Company’s press releases and public filings. The complaints request damages in unspecified amounts, costs and fees of bringing the action, and other unspecified relief.

On November 18, 2015, the S.D. of New York granted the Company’s motion to transfer the consolidated cases to the N.D. of California. On December 21, 2015, the N.D. of California granted the Company’s motion to deem the consolidated cases related to the Saratoga litigation, discussed below. On February 8, 2016, the N.D. of California granted an unopposed motion to appoint Plumbers and Pipefitters National Pension Fund as Lead Plaintiff. On March 19, 2016, Lead Plaintiff filed a consolidated amended complaint. On April 29, 2016, Marvell and each of the individual defendants each filed motions to dismiss. The hearing on the motions to dismiss took place on July 29, 2016 and the court took the matter under submission. On October 12, 2016, the Court granted Defendants’ motions to dismiss with leave to amend and granted lead plaintiff 30 days to file an amended complaint. The parties agreed that the plaintiffs shall file and serve an amended complaint by November 28, 2016. Plaintiffs filed and served the amended complaint on November 28, 2016. The Initial Case Management Conference took place on January 12, 2017. Marvell and co-defendants filed separate Motions to Dismiss on January 17, 2017. A further Case Management Conference and a hearing on defendants' Motions to Dismiss are both set for May 4, 2017. Trial is set for March 5, 2018.

Saratoga Litigation. On October 16, 2015, Saratoga Advantage Trust Technology & Communications Portfolio (“Saratoga”) filed an action asserting shareholder derivative claims ostensibly on behalf of the Company in the Superior Court of the State of California, County of Santa Clara. The complaint names eight current or former officers and/or directors (Sehat Sutardja, Weili Dai, Juergen Gromer, Arturo Krueger, John Kassakian, Randhir Thakur, Michael Rashkin, and Sukhi Nagesh) as defendants and asserts various California state law causes of action based on allegations that the Company and the named officers and directors made, caused to be made, or failed to correct false and/or misleading statements in the Company’s press releases and public filings, leading to the filing of securities class actions that allegedly damaged the Company. The Company was named as a nominal defendant. The complaint requested damages and restitution in unspecified amounts, equitable and/or injunctive relief, costs and fees of bringing the action, and other unspecified relief. On September 15, 2016, the case was dismissed with prejudice.

Surety Bonds

On May 14, 2014, the Company filed a Notice of Appeal to appeal the final judgment issued by the W.D of Pennsylvania in the CMU litigation. In order to stay the execution of the final judgment pending its appeal, the Company filed a supersedeas bond for $1.54 billion with the W.D. of Pennsylvania in the event the Company did not fully satisfy a final judgment as affirmed after the completion of all appellate proceedings. The bond was issued by a consortium of sureties authorized by the U.S. Treasury. In support of the bond, the Company entered into separate indemnity agreements with each of the sureties to indemnify the sureties from all costs and payments made under the bond. The indemnity agreements did not require collateral to be posted at the time of the issuance of the bond. However, the indemnity agreements provided that each of the sureties had the right to demand to be placed in funds or call for collateral under pre-defined events.

On November 14, 2014, the Company filed a second surety bond for $216 million and filed a commitment letter from the sureties to issue up to an additional $95 million in bonding under certain conditions. The second bond and commitment were secured by the Company’s campus located in Santa Clara, California with a carrying value of $126.7 million at January 28, 2017.

In connection with the settlement that was reached with CMU, the primary supersedeas bond that the Company entered into was reduced to $439 million and the secondary bond was adjusted to $311 million and both were discharged pursuant to an order releasing supersedeas bonds on April 21, 2016. For additional information, see CMU litigation under “Contingencies” above.

Indemnities, Commitments and Guarantees

During its normal course of business, the Company has made certain indemnities, commitments and guarantees under which it may be required to make payments in relation to certain transactions. These indemnities may include intellectual property indemnities to the Company’s customers in connection with the sales of its products, indemnities for liabilities associated with the infringement of other parties’ technology based upon the Company’s products, indemnities for general commercial obligations, indemnities to various lessors in connection with facility leases for certain claims arising from such facility or lease, and indemnities to directors and officers of the Company to the maximum extent permitted under the laws of Bermuda. In addition, the Company has contractual commitments to various customers, which could require the Company to incur costs to repair an epidemic defect with respect to its products outside of the normal warranty period if such defect were to occur. The duration of these indemnities, commitments and guarantees varies, and in certain cases, is indefinite. Some of these indemnities, commitments and guarantees do not provide for any limitation of the maximum potential future payments that the Company could be obligated to make. In general, the Company does not record any liability for these indemnities, commitments and guarantees in the accompanying consolidated balance sheets as the amounts cannot be reasonably estimated and are not considered probable. The Company does, however, accrue for losses for any known contingent liability, including those that may arise from indemnification provisions, when future payment is probable.

Benefit Plans	12 Months Ended
Benefit Plans	Jan. 28, 2017
Compensation and Retirement Disclosure [Abstract]
Benefit Plans	Benefit Plans The Company sponsors a 401(k) savings and investment plan that allows eligible U.S. employees to participate by making pre-tax contributions to the 401(k) plan ranging from 1% to 50% of eligible earnings subject to a required annual limit. The Company matches 100% of the first 4% of the employee’s contribution and 50% of the next 2%, up to a $3,000 maximum contribution. The Company made matching contributions to employees of $4.5 million in fiscal 2017, $4.9 million in fiscal 2016 and $5.1 million in fiscal 2015. As of January 28, 2017, the 401(k) plan offers a variety of investment alternatives, representing different asset classes. Employees may not invest in the Company’s common shares through the 401(k) plan. The Company also has voluntary defined contribution plans in various non-U.S. locations. In connection with these plans, the Company made contributions on behalf of employees totaling $11.8 million, $14.5 million and $18.5 million during fiscal 2017, 2016 and 2015, respectively. The Company also maintains a limited number of defined benefit plans for certain non-U.S. locations. Total costs under these plans were $0.1 million, $1.5 million and $0.1 million in fiscal 2017, 2016 and 2015, respectively.

Shareholders' Equity

12 Months Ended

Jan. 28, 2017

Equity [Abstract]

Shareholders' Equity

Shareholders’ Equity

Common and Preferred Stock

As of January 28, 2017, the Company is authorized to issue 992.0 million shares of $0.002 par value common stock and 8 million shares of $0.002 par value preferred stock. As of January 28, 2017 and January 30, 2016, no shares of preferred stock were outstanding.

1995 Stock Option Plan

In April 1995, the Company adopted the 1995 Stock Option Plan (the “Option Plan”). The Option Plan, as amended from time to time, had 383.4 million common shares reserved for issuance thereunder as of January 28, 2017. Options granted under the Option Plan generally have a term of 10 years and generally must be issued at prices equal to the fair market value of the stock on the date of grant. Incentive stock options granted to shareholders who own greater than 10% of the outstanding stock at the time of the grant may not have a term exceeding five years and these options must be issued at prices of at least 110% of the fair market value of the stock on the date of grant. The Company can also grant stock awards, which may be subject to vesting. Further, the Company can grant restricted stock unit (“RSU”) awards. RSU awards are denominated in shares of stock, but may be settled in cash or shares upon vesting, as determined by the Company at the time of grant. Awards under the Option Plan generally vest over 2 to 5 years.

As of January 28, 2017, approximately 98.6 million shares remained available for future issuance under the Option Plan.

Fiscal 2017. In August 2016, the Company granted performance-based equity awards to each of its executive officers who then joined the Company. The Company also granted performance-based equity awards to an additional four executive officers who later joined the Company in September, November and December of 2016. These equity awards include RSU’s which vest based on the achievement of certain financial goals (“Financial Performance RSU”). The Financial Performance RSUs will be earned on the achievement of certain financial operating metrics to be measured as of the end of fiscal 2018 and will vest on the third anniversary of the respective vesting commencement dates. Shares granted under these Financial Performance RSUs (based on 100% expected achievement) are reported in the table presented below as “Performance-Based.” The executive officers were also granted equity awards which shall vest based on total shareholder return (each a “Total Shareholder Return Award”). The Total Shareholder Return Awards will vest on the third anniversary of the respective vesting commencement dates based on the achievement of performance objectives relating to relative total shareholder return of the Company’s common shares as compared to that of comparable companies of the Philadelphia Semiconductor Sector Index over a performance period defined in the award. These Total Shareholder Return Awards are reported in the table presented below as “Market-Based.”

Fiscal 2016. In April 2015, the Company granted performance-based equity awards to each of its executive officers, which were based on their achievement of certain performance goals for a performance period beginning in fiscal 2016. These equity awards included RSUs which would vest based on the achievement of certain financial goals (each a “Financial Performance RSU”), and performance awards for which a portion would vest based on the achievement of individual strategic objectives (each a “Strategic Objective Award”) and a portion would vest based on total shareholder return (each a “Total Shareholder Return Award”). These awards are reported as “Performance-Based,” except for the Total Shareholder Return Award which is reported as “Market-Based.” The Financial Performance RSUs would be earned based on the achievement of revenue and modified non-GAAP operating income that have been established at “threshold,” “target” and “maximum” levels that would vest on the first anniversary of the vest commencement date. The Strategic Objective Awards would also vest on the first anniversary of the commencement date at the target level based on the achievement of individual strategic goals and, with respect to a portion of each Strategic Objective Award, the further achievement of either the revenue or modified non-GAAP operating income objective established for the Financial Performance RSU. The Total Shareholder Return Awards would vest on the second anniversary of the commencement date based on the Company’s stock price performance in comparison to the Philadelphia Semiconductor Sector Index.

Fiscal 2015. In April 2014, the Company granted performance-based equity awards to each of its executive officers which were based on their achievement of certain performance goals in fiscal 2015 and 2016. These equity awards included RSUs which would vest based on financial performance criteria (“Financial Performance RSU”) and restricted stock units which vest based on both financial performance criteria and individual strategic goals (“Strategic Performance Award”). The Financial Performance RSUs would be earned based on the achievement of revenue and modified non-GAAP operating income that have been established at “threshold,” “target” and “maximum” levels. Each Financial Performance RSU would vest 50% on the first anniversary of the commencement date based on achievement of fiscal 2015 financial performance criteria and 50% on the second anniversary of the vesting commencement date based on the achievement of fiscal 2016 financial performance criteria. The Strategic Performance Awards would vest based on achievement at the threshold level of either the revenue or modified non-GAAP operating income objective established for the Financial Performance RSU, in addition to the achievement of additional individual strategic goals. Each Strategic Performance Award would vest 50% on the first anniversary of the commencement date based on achievement of fiscal 2015 individual strategic goals and 50% on second anniversary date based on the achievement of the fiscal 2016 individual strategic goals.

In June 2014, the Company granted performance-based RSU (“PSUs”) to certain members of senior management. Pursuant to the PSUs, each eligible employee was entitled to vest in a certain number of shares based on such employee’s achievement of individual financial and strategic performance goals for fiscal 2015, including, for example, net revenue and operating expense targets, and other individual strategic milestones. The actual number of shares that would vest for each eligible employee was based on the achievement of such performance goals determined at the end of fiscal 2015 and would vest over two years, with 50% vesting on April 1, 2015 and 50% vesting on April 1, 2016.

Outside Director Equity Compensation Policy

In September 2016, the Company’s Board of Directors approved the termination of the 2007 Directors’ Stock Incentive Plan, (“2007 Director Plan”) that was initially adopted in October 2007 and it approved a new Outside Director Equity Compensation Policy, which governs the granting of equity awards to non-employee directors under the Option Plan. At the annual general meeting of shareholders held in June 2015, the shareholders approved an amendment to the Option Plan to enable a full range of awards to be granted to non-employee directors. Under the newly adopted Outside Director Compensation Policy, each outside director upon election or appointment at an annual meeting of shareholders will be granted an RSU award under the 1995 Stock Option Plan for a number of shares with an aggregate fair market value equal to $220,000 on the grant date. In no event shall an outside director be awarded an annual RSU award for more than 20,000 shares. The RSU award vests 100% on the earlier of the date of the next annual general meeting of shareholders or the one-year anniversary of the date of grant.

2000 Employee Stock Purchase Plan

Under the 2000 Employee Stock Purchase Plan, as amended and restated on October 31, 2011 (the “ESPP”), participants purchase the Company’s stock using payroll deductions, which may not exceed 15% of their total cash compensation. Pursuant to the terms of the current ESPP, the “look-back” period for the stock purchase price is 24 months. Offering and purchase periods begin on December 8 and June 8 of each year. Participants enrolled in a 24-month offering period will continue in that offering period until the earlier of the end of the offering period or the reset of the offering period. A reset occurs if the fair market value of the Company’s common shares on any purchase date is less than it was on the first day of the offering period. Participants in a 24-month offering period will be granted the right to purchase common shares at a price per share that is 85% of the lesser of the fair market value of the shares at (i) the participant’s entry date into the two-year offering period or (ii) the end of each six-month purchase period within the offering period.

Under the ESPP, a total of 2.3 million shares were issued in fiscal 2017 at a weighted-average price of $7.33 per share, a total of 5.9 million shares were issued in fiscal 2016 at a weighted-average price of $10.00 per share and a total of 9.7 million shares were issued in fiscal 2015 at a weighted-average price of $7.67 per share. As of January 28, 2017, there was $16.2 million of unamortized compensation cost related to the ESPP.

As of January 28, 2017, approximately 29.5 million shares remained available for future issuance under the ESPP.

Option Plan and Stock Award Activity

Stock option activity under the Company’s stock option and stock incentive plans is included in the following table (in thousands, except for per share amounts):



	Time-Based Options				Market-Based Options				Total
	Number of Shares		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price
Balance at February 1, 2014	49,156		$	13.40	2,623		$	15.43	51,779		$	13.51
Granted	6,365		$	15.33	—		—		6,365		$	15.33
Exercised	(3,732	)	$	10.19	—		—		(3,732	)	$	10.19
Canceled/Forfeited	(4,649	)	$	14.66	(391	)	$	15.43	(5,040	)	$	14.72
Balance at January 31, 2015	47,140		$	13.79	2,232		$	15.43	49,372		$	13.88
Granted	6,170		$	14.13	—		—		6,170		$	14.13
Exercised	(2,225	)	$	9.79	—		—		(2,225	)	$	9.79
Canceled/Forfeited	(10,211	)	$	15.68	(76	)	$	15.43	(10,287	)	$	15.68
Balance at January 30, 2016	40,874		$	13.59	2,156		$	15.43	43,030		$	13.68
Granted	2,104		$	9.99	—		—		2,104		$	9.99
Exercised	(5,558	)	$	10.35	—		—		(5,558	)	$	10.35
Canceled/Forfeited	(12,324	)	$	16.44	(2,156	)	$	15.43	(14,480	)	$	16.29
Balance at January 28, 2017	25,096		$	12.61	—				25,096		$	12.61
Vested or expected to vest at January 28, 2017	24,253		$	12.57

For time-based stock options vested and expected to vest at January 28, 2017, the aggregate intrinsic value was $68.0 million. For time-based stock options exercisable at January 28, 2017, the aggregate intrinsic value was $45.7 million. The aggregate intrinsic value of stock options exercised during fiscal 2017, 2016 and 2015 was $19.8 million, $9.7 million and $19.3 million, respectively. The market-based stock options automatically expired in April 2016 since the market price conditions were not met within the required five years from date of grant. The Company’s closing stock price of $15.09 as reported on the NASDAQ Global Select Market as of January 27, 2017 was used to calculate the aggregate intrinsic value for all in-the-money options.

Outstanding options and exercisable options information by range of exercise prices as of January 28, 2017 was as follows:



				Outstanding Options				Exercisable Options
Range of Exercise Prices				Number of Shares (in Thousands)	Weighted Average Remaining Contractual Term (in Years)	Weighted Average Exercise Price		Number of Shares (in Thousands)	Weighted Average Exercise Price
$	5.70	$	10.47	3,842	4.84	$	8.11	2,214	$	6.94
$	10.76	$	10.76	7,004	6.16	$	10.76	4,344	$	10.76
$	10.80	$	14.35	6,047	5.79	$	13.13	2,630	$	11.72
$	14.45	$	15.87	5,540	5.82	$	15.40	2,385	$	15.24
$	15.91	$	21.62	2,663	1.19	$	16.95	2,599	$	16.96
Total				25,096	5.27	$	12.61	14,172	$	12.23

As of January 28, 2017, the unamortized compensation expense for time-based stock options was $15.5 million. The unamortized compensation expense for time-based options will be amortized on a straight-line basis and is expected to be recognized over a weighted-average period of 1.4 years.

Activity related to the non-vested portion of the restricted stock units is included in the following table (in thousands, except for share prices):



	Time-Based				Performance-Based					Market-Based					Total
	Number of Shares		Weighted Average Grant Date Fair Value		Number of Shares			Weighted Average Grant Date Fair Value		Number of Shares			Weighted Average Grant Date Fair Value		Number of Shares		Weighted Average Grant Date Fair Value
Balance at February 1, 2014	11,254		$	14.14	100			$	10.52						11,354		$	14.11
Granted	5,534		$	15.20	1,277		*	$	14.98						6,811		$	15.16
Vested	(5,938	)	$	13.96	(3	)		$	10.52						(5,941	)	$	13.96
Canceled/Forfeited	(1,102	)	$	14.32	(120	)		$	11.23						(1,222	)	$	14.02
Balance at January 31, 2015	9,748		$	14.84	1,254			$	14.99						11,002		$	14.85
Granted	5,689		$	12.88	669		*	$	14.08	407			$	12.24	6,765		$	12.96
Vested	(5,139	)	$	15.06	(658	)		$	15.15	—			$	—	(5,797	)	$	15.07
Canceled/Forfeited	(1,955	)	$	13.99	(288	)		$	14.39	(54	)		$	12.24	(2,297	)	$	14.00
Balance at January 30, 2016	8,343		$	13.57	977			$	14.43	353			$	12.24	9,673		$	13.61
Granted	9,139		$	9.83	366		*	$	13.91	612		*	$	11.94	10,117		$	10.11
Vested	(5,490	)	$	13.95	(155	)		$	14.15	—			—		(5,645	)	$	13.95
Canceled/Forfeited	(2,067	)	$	10.69	(875	)		$	14.45	(406	)		$	12.39	(3,348	)	$	11.88
Balance at January 28, 2017	9,925		$	10.52	313			$	13.91	559			$	11.80	10,797		$	10.69


*	Amounts represent the target number of restricted stock units at grant date. For awards granted to our executive officers, up to 200% of the target restricted stock units may vest if the maximum level for performance goals is achieved.

In connection with the performance-based equity awards granted in fiscal 2016 to each of the Company’s executive officers, a total of 33,616 shares vested on April 1, 2016 based on achieving certain individual strategic goals as evaluated by the Executive Compensation Committee of the Company’s Board of Directors. No shares vested for the achievement of financial performance goals since the financial performance criteria were below the threshold level. The amount of canceled shares reported in the table above includes the unvested shares that were not earned.

In connection with the performance-based equity awards granted in fiscal 2015 to each of the Company’s executive officers, a total of 478,001 shares vested on April 1, 2015 in connection with the first performance period completed at the end of fiscal 2015. Of this amount, an additional 107,954 shares are included as granted in the table above for fiscal 2015 since each executive officer achieved greater than their target shares for one of the financial performance goals. The amount of canceled shares reported in the table above includes the portion of unvested shares that were not earned since performance objectives for each executive officer’s other financial and strategic performance goals were not fully achieved. No shares will be issued in connection with the second performance period since the financial and strategic performance goals for fiscal 2016 were not achieved.

In connection with the PSUs granted in fiscal 2015 to certain members of senior management, final evaluation for each individual’s achievement of their performance was measured in the first quarter of fiscal 2016. As a result, a total of 360,723 shares vested on April 1, 2015 and are included in the above table. There was no material adjustment to share-based compensation expense related to these performance-based restricted stock units in fiscal 2016. The amount of canceled shares reported in the table above includes the portion of unvested shares that were not earned since certain performance achievements were not fully achieved.

The aggregate intrinsic value of restricted stock units expected to vest as of January 28, 2017 was $152.4 million. The number of restricted stock units that are expected to vest is 10.1 million shares.

As of January 28, 2017, unamortized compensation expense related to restricted stock units was $64.2 million. The unamortized compensation expense for restricted stock units will be amortized on a straight-line basis and is expected to be recognized over a weighted-average period of 1.4 years.

Share-Based Compensation

The following table presents details of share-based compensation expenses by functional line item (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Continuing operations:
Cost of goods sold	$	8,334	$	7,787	$	7,972
Research and development	78,136		92,054		89,131
Selling and marketing	10,243		10,242		10,623
General and administrative	8,047		15,878		23,292
Share-based compensation - continuing operations	$	104,760	$	125,961	$	131,018
Discontinued operations:
Cost of goods sold	187		129		—
Research and development	8,306		6,738		5,301
Selling and marketing	649		864		846
General and administrative	68		87		81
Share-based compensation - discontinued operations	9,210		7,818		6,228
Total share-based compensation	$	113,970	$	133,779	$	137,246

Share-based compensation capitalized in inventory was $0.9 million at January 28, 2017 and $1.5 million at both January 30, 2016 and January 31, 2015.

Upon the termination of certain members of our executive management in April 2016, it was determined that the vesting in certain of their unvested stock awards was no longer probable. As a result, the Company recorded a reversal of the previously recognized related share-based compensation expense in fiscal 2017.

Valuation Assumptions

The expected volatility for awards granted during fiscal 2017, 2016 and 2015 was based on an equally weighted combination of historical stock price volatility and implied volatility derived from traded options on the Company’s stock in the marketplace. The Company believes that the combination of historical volatility and implied volatility provides a better estimate of future stock price volatility.

The expected dividend yield is calculated by dividing the current annualized dividend by the closing stock price on the date of grant of the option.

The following weighted average assumptions were used for each respective period to calculate the fair value of each time-based stock option award on the date of grant using the Black-Scholes option pricing model:



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Time-based Stock Options:
Weighted average fair value	$	2.92		$	3.93		$	4.35
Expected volatility	40		%	34		%	35		%
Expected term (in years)	5.2			5.4			5.0
Risk-free interest rate	1.3		%	1.6		%	1.6		%
Expected dividend yield	2.5		%	1.8		%	1.6		%

There have been no market-based stock option grants since fiscal 2012, when the Company issued 3.1 million stock options with a market-based condition for a group of senior employees. The market price conditions were not met within the five years from date of grant and these stock options automatically expired in April 2016.

The following weighted-average assumptions were used for each respective period to calculate the fair value of common shares to be issued under the ESPP on the date of grant using the Black-Scholes option pricing model:



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Employee Stock Purchase Plan:
Estimated fair value	$	3.83		$	3.24		$	4.10
Expected volatility	39		%	41		%	30		%
Expected term (in years)	1.2			1.3			1.3
Risk-free interest rate	0.7		%	0.6		%	0.3		%
Expected dividend yield	1.9		%	2.4		%	1.6		%

The following weighted-average assumptions were used for each respective period to calculate the fair value of common shares to be issued under Total Shareholder Return performance awards on the date of grant using the Monte Carlo pricing model:



	Year Ended
	January 28, 2017		January 30, 2016
Total Shareholder Return Awards:
Expected term (in years)	2.9		2.0
Expected volatility	36	%	27	%
Average correlation coefficient of peer companies	0.5		0.4
Risk-free interest rate	0.9	%	0.5	%
Expected dividend yield	2.1	%	1.7	%

The correlation coefficients are calculated based upon the price data used to calculate the historical volatilities and is used to model the way in which each entity tends to move in relation to its peers.

Share Repurchase Program

On November 17, 2016, the Company announced that its Board of Directors authorized a $1.0 billion share repurchase plan. The current stock repurchase program replaced in its entirety the prior $3.25 billion stock repurchase program, which had approximately $115.0 million of repurchase authority remaining as of November 27, 2016. The Company intends to effect share repurchases in accordance with the conditions of Rule 10b-18 under the Exchange Act but may also make repurchases in the open market outside of Rule 10b-18 or in privately negotiated transactions. The share repurchase program will be subject to market conditions and other factors, and does not obligate the Company to repurchase any dollar amount or number of its common shares and the repurchase program may be extended, modified, suspended or discontinued at any time.

The Company repurchased 13.3 million of its common shares for $183.1 million, 19.7 million of its common shares for $260.9 million and 5.1 million of its common shares for $65.0 million in cash during fiscal 2017, 2016 and 2015, respectively. All of the repurchased shares were retired immediately after the repurchases were completed. The Company records all repurchases, as well as investment purchases and sales, based on their trade date. From August 2010 when the Company’s Board of Directors initially authorized a share repurchase program through January 28, 2017, a total of 254.9 million shares have been repurchased to date under the Company’s share repurchase program for a total $3.3 billion in cash and there was $884.0 million remaining available for future share repurchases.

Subsequent to the year ended January 28, 2017 through March 15, 2017, the Company repurchased an additional 2.7 million of its common shares for $43.7 million at an average price per share of $15.91.

Dividends

On March 16, 2017, the Company announced that its board of directors declared a cash dividend of $0.06 per share payable on April 20, 2017 to shareholders of record as of April 4, 2017.

Segment and Geographic Information

12 Months Ended

Jan. 28, 2017

Segment Reporting [Abstract]

Segment and Geographic Information

The Company operates in one reportable segment — the design, development and sale of integrated circuits. The chief executive officer was identified as the chief operating decision maker (“CODM”) for the years ended January 28, 2017, January 30, 2016 and January 31, 2015. The Company’s CODM is ultimately responsible and actively involved in the allocation of resources and the assessment of the Company’s performance. The fact that the Company operates in only one reportable segment is based on the following:


•	The Company uses a highly-integrated approach in developing its products in that discrete technologies developed by the Company are frequently integrated across many of its products. Substantially all of the Company’s integrated circuits are manufactured under similar manufacturing processes.


•	The Company’s organizational structure is based along functional lines. Each of the functional department heads reports directly to the CODM. Shared resources in the Company also report directly to the CODM or to a direct report of the CODM.


•	The assessments of performance across the Company, including assessment of the Company’s incentive compensation plan, are based largely on operational performance and consolidated financial performance.


•	The decisions on allocation of resources and other operational decisions are made by the CODM based on his direct involvement with the Company’s operations and product development.

The following tables present net revenue and long-lived asset information based on geographic region. Net revenue is based on the destination of the shipments and long-lived assets are based on the physical location of the assets (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Net Revenue:
United States	$	51,416	$	60,119	$	61,470
China	1,239,931		1,509,244		2,171,299
Thailand	113,778		189,299		294,706
Malaysia	286,267		302,953		377,903
Philippines	283,345		211,602		254,381
Others	342,937		375,999		477,447
	$	2,317,674	$	2,649,216	$	3,637,206



	January 28, 2017		January 30, 2016
Property and equipment, net:
China	$	16,484	$	22,294
Israel	12,133		15,069
Singapore	54,054		68,212
United States	147,552		173,158
Others	13,174		18,045
	$	243,397	$	296,778

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8981-108599

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9038-108599

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8971-108599

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8595-108599

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8380-108599

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8933-108599

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 26
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8844-108599

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8984-108599

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9031-108599

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9054-108599

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8864-108599

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8924-108599

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e8906-108599

+ Details

Related Party Transactions	12 Months Ended
Related Party Transactions	Jan. 28, 2017
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company, through one of its subsidiaries, is a party to technology license agreements with each of VeriSilicon Holdings Co., Ltd. ("VeriSilicon") and Vivante Corporation (“Vivante”). Pursuant to its agreements with VeriSilicon, which has been amended from time to time, and a services agreement with VeriSilicon, the Company paid $1.5 million, $1.8 million and $3.7 million to VeriSilicon during fiscal 2017, 2016 and 2015, respectively. As of January 28, 2017, the Company had $0.1 million of liability to VeriSilicon. Pursuant to its agreements with Vivante, which has been amended from time to time, and a services agreement with Vivante, the Company paid $3.5 million, $4.0 million and $9.1 million to Vivante during fiscal 2017, 2016 and 2015, respectively. As of January 28, 2017, the Company had no liability to Vivante. VeriSilicon acquired Vivante in late 2016. Dr. Sehat Sutardja and Ms. Weili Dai, the Company’s former Chairman and Chief Executive Officer and President and a director of the Company, respectively, and currently greater than 10% shareholder of the Company, are husband and wife. Ms. Dai’s brothers (and Dr. Sutardja’s brothers-in-law) Wayne Dai and Weijin Dai are executive officers and board members of VeriSilicon. Dr. Sutardja and Ms. Dai are shareholders (directly and indirectly) in VeriSilicon. In February 2015, the Executive Compensation Committee (“Committee”) of the Company’s Board of Directors approved a cash payment of approximately $15.4 million to Dr. Sehat Sutardja. The U.S. Court of Federal Claims ruled against Dr. Sutardja in his legal challenge with the Internal Revenue Service and the California Franchise Tax Board related to the tax treatment of several stock options granted in fiscal 2004. After discussing and evaluating the alternatives to a continuing legal challenge of the court’s determination, the likelihood of success of further appeal by Dr. Sutardja and the potential negative impact on the Company of a continuation of the case regardless of the outcome, the Committee determined to provide Dr. Sutardja with relief from the financial effects of the penalty taxes. Accordingly, the Committee approved the cash payment to Dr. Sutardja equal to the amount of his penalty taxes owed under the Tax Codes, plus accrued interest owed with respect to such liabilities, all grossed-up for income taxes that will be owed by Dr. Sutardja on receipt of such cash payment. The Company recorded the payment in general and administrative expense in fiscal 2016. A payment of $8.4 million was made to Dr. Sutardja in fiscal 2016 representing reimbursement for the U.S. federal tax portion. As of January 28, 2017, the Company had a remaining $7.0 million liability to Dr. Sutardja with respect to the California tax portion.

Carnegie Mellon University Settlement	12 Months Ended
Carnegie Mellon University Settlement	Jan. 28, 2017
Commitments and Contingencies Disclosure [Abstract]
Carnegie Mellon University Settlement	Carnegie Mellon University Settlement In February 2016, the Company and CMU settled their patent infringement lawsuit pursuant to a court-ordered mediation and entered into a Settlement Agreement and Patent License (the “Agreement”). The parties agreed to mutual release of claims, license and covenant not to sue provisions for which the Company paid an aggregate of $750 million to CMU in fiscal 2017. See CMU litigation under “Note 10 - Commitments and Contingencies” for further information about the lawsuit. The Agreement was accounted for as a multiple-element arrangement and accordingly, a valuation was completed to determine the estimated fair value of each identifiable element. As a result, the Company allocated $654.7 million to the mutual release of claims and covenant not to sue provisions; $81.3 million to the licensing of intellectual property in fiscal 2016; and the remaining $14.0 million representing the future use of the license through April 2018. The $654.7 million for the mutual release of claims and covenant not to sue was recorded in fiscal 2016 as a settlement charge in operating expenses since there is no future benefit. The $81.3 million license fee was recorded in fiscal 2016 as a charge in cost of goods sold for past use of the license. The $14.0 million representing the future use of the license, is to be recognized in cost of goods sold over the remaining term of the license from February 2016 through April 2018. Accordingly, the Company recorded $6.2 million to cost of goods sold in fiscal 2017.

Changes in the Company's Organization	12 Months Ended
Changes in the Company's Organization	Jan. 28, 2017
Reorganizations [Abstract]
Changes in the Company's Organization	Changes in the Company's Organization In April 2016, the employment of Dr. Sehat Sutardja as Chief Executive Officer and Ms. Weili Dai as President was terminated by the Company’s Board of Directors. The Board of Directors then formed an Interim Office of the Chief Executive and appointed Maya Strelar-Migotti, Executive Vice President of the Smart Networked Devices and Solutions Business Group, and Dr. Pantelis Alexopoulos, Executive Vice President of the Storage Business Group, as Interim Co-Chief Executive Officers. In April 2016, the Company announced that it entered into an agreement with Starboard Value LP (“Starboard”), regarding the composition of its Board of Directors. Under the terms of the agreement, the Company elected Peter A. Feld, Richard S. Hill, Oleg Khaykin, Michael Strachan and Robert Switz to serve on its board. The agreement specifies that the Board would recommend and the Company would support and solicit proxies only for the election at the 2016 annual general meeting of Messrs. Feld, Hill, Khaykin, Strachan and Switz, the four independent directors serving on the Board immediately prior to the execution of the agreement, Dr. Juergen Gromer, Dr. John G. Kassakian, Arturo Krueger and Dr. Randhir Thakur, and Matthew J. Murphy, who joined the Company in July 2016 after the Board of Directors appointed him to serve as the Company’s President and Chief Executive Officer in June 2016. Upon the commencement of Mr. Murphy’s employment, the Board subsequently appointed Richard S. Hill, the Chairman of the Board, as the Company’s Interim Principal Executive Officer, to serve in that capacity until the Company filed its Quarterly Report on Form 10-Q for the second quarter of fiscal 2017 (“Q217 Form 10-Q”). Mr. Murphy assumed the role of the Company’s principal executive officer immediately following the filing of the Q217 Form 10-Q. In August 2016, the Company announced the appointment of Jean Hu as Chief Financial Officer effective August 22, 2016. David P. Eichler, the Company’s Interim Chief Financial Officer and principal financial officer, ceased serving as the Company’s principal financial officer upon Ms. Hu’s appointment as Chief Financial Officer. In September 2016, the Company announced the departure of Dr. Zining Wu as the Company’s Chief Technical Officer. In October 2016, the Company announced the appointment of David Caron as Chief Accounting Officer and Controller. At the Company’s Annual General Meeting of Shareholders held on November 8, 2016 (the “Annual Meeting”), shareholders whose shares were present either in person or by proxy voted upon the election of directors to the Board of Directors. The shareholders elected the following directors to serve until the next annual general meeting of shareholders: Peter Feld; Richard Hill; Oleg Khaykin; Matthew Murphy; Michael Strachan; Robert Switz; and Randhir Thakur. Immediately following the Annual Meeting, the terms of directors Dr. Sehat Sutardja, Weili Dai, Dr. Juergen Groemer, Dr. John Kassakian and Arturo Krueger expired. On November 15, 2016, the Board of Directors appointed Dr. Thakur to serve on the Audit Committee of the Board of Directors, effective immediately. In December 2016, the Board of Directors appointed Tudor Brown as a member of the Board of Directors and the Executive Compensation Committee. In January 2017, Ms. Strelar-Migotti left the Company.

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS

12 Months Ended

Jan. 28, 2017

Valuation and Qualifying Accounts [Abstract]

SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS

SCHEDULE II

VALUATION AND QUALIFYING ACCOUNTS

(in thousands)



	Balance at Beginning of Year		Additions		Deductions			Balance at End of Year
Fiscal year ended January 28, 2017
Allowance for doubtful accounts and sales return reserve	$	2,762	$	4,456	$	(5,834	)	$	1,384
Deferred tax valuation allowance	$	424,914	$	31,627	$	—		$	456,541
Fiscal year ended January 30, 2016
Allowance for doubtful accounts and sales return reserve	$	2,112	$	2,614	$	(1,964	)	$	2,762
Deferred tax valuation allowance	$	382,796	$	42,118	$	—		$	424,914
Fiscal year ended January 31, 2015
Allowance for doubtful accounts and sales return reserve	$	2,294	$	3,041	$	(3,223	)	$	2,112
Deferred tax valuation allowance	$	335,890	$	46,906	$	—		$	382,796

The Company and its Significant Accounting Policies (Policies)

12 Months Ended

Jan. 28, 2017

Accounting Policies [Abstract]

Basis of Presentation

Discontinued Operations

Use of Estimates

Principles of Consolidation

Cash and Cash Equivalents

Investments

Impairment of Investments


•	the Company has the intent to sell the security;


•	it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost base; or


•	a credit loss exists insofar as the Company does not expect to recover the entire recognized amortized cost of the security.

Derivative Financial Instruments

Concentration of Credit Risk and Significant Customers



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Customer:
Western Digital*	21	%	19	%	20	%
Toshiba	13	%	**%		**%
Seagate	9	%	14	%	13	%
Wintech	10	%	**%		11	%

* The percentage of net revenues reported for Western Digital for fiscal year 2017 includes net revenue of HGST and SanDisk that became subsidiaries of Western Digital in late fiscal 2016.
** Less than 10% of net revenue

Inventories

Property and Equipment, Net

Goodwill

Long-Lived Assets and Intangible Assets

Foreign Currency Transactions

Revenue Recognition

Advertising Expense

Advertising costs are expensed as incurred.

Share-Based Compensation

The fair value of each restricted stock unit is estimated based on the market price of the Company’s common shares on the date of grant less the expected dividend yield.

Comprehensive Income (Loss)

Accounting for Income Taxes

Warranty

Recent Accounting Pronouncements

Accounting Pronouncements Recently Adopted

Accounting Pronouncements Not Yet Effective

The Company and its Significant Accounting Policies (Tables)

12 Months Ended

Jan. 28, 2017

Accounting Policies [Abstract]

Schedule of Net Revenue Attributable to Significant Customers

Net revenue attributable to significant customers whose revenues as a percentage of net revenue was 10% or greater of total net revenues is presented in the following table:



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Customer:
Western Digital*	21	%	19	%	20	%
Toshiba	13	%	**%		**%
Seagate	9	%	14	%	13	%
Wintech	10	%	**%		11	%

* The percentage of net revenues reported for Western Digital for fiscal year 2017 includes net revenue of HGST and SanDisk that became subsidiaries of Western Digital in late fiscal 2016.
** Less than 10% of net revenue

Discontinued Operations (Tables)

12 Months Ended

Jan. 28, 2017

Discontinued Operations and Disposal Groups [Abstract]

Major Classes of Assets and Liabilities and Results of Operations of Discontinued Operations



	January 28, 2017		January 30, 2016
Current assets held for sale:
Inventory	$	8,154	$	9,059
Property and equipment, net	2,898		2,762
Goodwill	26,532		26,532
Acquired intangible assets, net	3,799		6,063
Other	1,490		679
Current assets held for sale for discontinued operations	42,873		45,095
Other assets held for sale
Property and equipment, net	2,973		—
Total assets of the disposal group classified as held for sale	$	45,846	$	45,095
Current liabilities held for sale:
Deferred Income	$	1,670	$	1,749
Total liabilities of the disposal group classified as held for sale	$	1,670	$	1,749



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Net Revenue	$	98,755		$	76,612		$	69,757
Operating costs and expenses:
Cost of goods sold	60,799			52,219			44,281
Research and development	53,784			59,524			67,263
Selling and marketing	4,750			4,684			4,325
General and administrative	963			769			795
Amortization of acquired intangible assets	325			650			650
Total operating costs and expenses	120,621			117,846			117,314
Loss from discontinued operations before income taxes	(21,866		)	(41,234		)	(47,557		)
Provision for income taxes	977			1,011			884
Net loss from discontinued operations	$	(22,843	)	$	(42,245	)	$	(48,441	)

- Definition

Tabular disclosure of information related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
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-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721533-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Topic 205
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-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721683-107760

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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 205
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 205
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 205
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-Paragraph 5D
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721677-107760

+ Details

Investments (Tables)

12 Months Ended

Jan. 28, 2017

Investments, Debt and Equity Securities [Abstract]

Schedule of Available-for-sale Securities Reconciliation

The following tables summarize the Company’s investments (in thousands):



	January 28, 2017
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Short-term investments:
Available-for-sale:
Corporate debt securities	$	432,603	$	281	$	(776	)	$	432,108
U.S. government and agency debt	185,584		86		(283		)	185,387
Asset backed securities	45,541		33		(47		)	45,527
Foreign government and agency debt	13,425		—		(50		)	13,375
Municipal debt securities	27,916		4		(49		)	27,871
Held-to-Maturity:
Time deposits	150,000		—		—			150,000
Total short-term investments	855,069		404		(1,205		)	854,268
Long-term investments:
Available-for-sale:
Auction rate securities	4,615		—		—			4,615
Total long-term investments	4,615		—		—			4,615
Total investments	$	859,684	$	404	$	(1,205	)	$	858,883



	January 30, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Short-term investments:
Available-for-sale:
Corporate debt securities	$	558,337	$	766	$	(1,282	)	$	557,821
U.S. government and agency debt	317,595		64		(254		)	317,405
Asset backed securities	76,711		81		(56		)	76,736
Foreign government and agency debt	21,370		2		(14		)	21,358
Municipal debt securities	31,211		45		(7		)	31,249
Total short-term investments	1,005,224		958		(1,613		)	1,004,569
Long-term investments:
Available-for-sale:
Auction rate securities	11,296		—		—			11,296
Total long-term investments	11,296		—		—			11,296
Total investments	$	1,016,520	$	958	$	(1,613	)	$	1,015,865

Gross Realized Gains and Losses on Sales of Available-for-Sale Securities

Gross realized gains and gross realized losses on sales of available-for-sale securities are presented in the following table (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Gross realized gains	$	2,047		$	1,654		$	1,618
Gross realized losses	(547		)	(1,923		)	(169		)
Impairment loss	—			(1,204		)	—
Total net realized gains (losses)	$	1,500		$	(1,473	)	$	1,449

Investments Classified by Contractual Maturity Date

The contractual maturities of available-for-sale securities are presented in the following table (in thousands):



	January 28, 2017				January 30, 2016
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
Due in one year or less	$	423,151	$	423,058	$	304,117	$	304,035
Due between one and five years	423,669		422,995		689,847		689,279
Due over five years	12,864		12,830		22,556		22,551
	$	859,684	$	858,883	$	1,016,520	$	1,015,865

Unrealized Loss Position Investments



	January 28, 2017
	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
Corporate debt securities	$	199,382	$	(751	)	$	16,063	$	(25	)	$	215,445	$	(776	)
U.S. government and agency debt	94,064		(283		)	—		—			94,064		(283		)
Asset backed securities	16,754		(47		)	—		—			16,754		(47		)
Foreign government and agency debt	11,875		(48		)	1,499		(2		)	13,374		(50		)
Municipal debt securities	17,450		(47		)	1,248		(2		)	18,698		(49		)
Total securities	$	339,525	$	(1,176	)	$	18,810	$	(29	)	$	358,335	$	(1,205	)



	January 30, 2016
	Less than 12 months					12 months or more					Total
	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss			Fair Value		Unrealized Loss
Corporate debt securities	$	283,138	$	(1,237	)	$	14,383	$	(45	)	$	297,521	$	(1,282	)
U.S. government and agency debt	263,325		(254		)	—		—			263,325		(254		)
Asset backed securities	46,646		(56		)	—		—			46,646		(56		)
Foreign government and agency debt	16,458		(14		)	—		—			16,458		(14		)
Municipal debt securities	2,943		(5		)	1,571		(2		)	4,514		(7		)
Total securities	$	612,510	$	(1,566	)	$	15,954	$	(47	)	$	628,464	$	(1,613	)

Supplemental Financial Information (Tables)

12 Months Ended

Jan. 28, 2017

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Schedule of Cash and Cash Equivalents



	January 28, 2017		January 30, 2016
Cash and cash equivalents:
Cash	$	651,953	$	669,312
Cash equivalents:
Time deposits	67,000		209,405
U.S. government and agency debt	17,497		184,374
Money market funds	36,122		160,400
Corporate debt securities	31,280		54,689
Municipal debt securities	8,740		—
Foreign government and agency debt	1,500		—
Cash and cash equivalents	$	814,092	$	1,278,180

Schedule of Provision for Sales Returns and Allowances



	January 28, 2017		January 30, 2016
Provision for sales returns and allowances:
Sales returns	$	470	$	1,873
Doubtful accounts	914		889
	$	1,384	$	2,762

Schedule of Inventories



	January 28, 2017		January 30, 2016
Inventories:
Work-in-process	$	110,083	$	125,800
Finished goods	61,886		75,158
Inventories	$	171,969	$	200,958

Schedule of Property and Equipment, Net



	January 28, 2017			January 30, 2016
Property and equipment, net:
Machinery and equipment	$	578,248		$	575,954
Buildings and building improvements	194,290			194,247
Computer software	99,186			102,840
Land	53,373			53,373
Leasehold improvements	49,004			50,192
Furniture and fixtures	23,903			27,118
Construction in progress	11,240			1,353
	1,009,244			1,005,077
Less: Accumulated depreciation	(765,847		)	(708,299		)
Property and equipment, net	$	243,397		$	296,778

Schedule of Other Non-current Assets



	January 28, 2017		January 30, 2016
Other non-current assets:
Technology and other licenses	$	53,254	$	48,091
Deferred tax assets	26,608		34,505
Investments in privately-held companies	5,787		5,804
Prepaid land use rights	12,810		13,123
Deposits	3,756		51,512
Other	11,109		10,996
Other non-current assets	$	113,324	$	164,031

Schedule of Accrued Liabilities



	January 28, 2017		January 30, 2016
Accrued liabilities:
Accrued rebates	$	26,095	$	41,320
Restructuring liability	23,150		3,842
Accrued royalties	17,349		16,217
Technology license obligations	21,905		17,985
Accrued legal expense	5,127		9,761
Other	49,865		42,935
Accrued liabilities	$	143,491	$	132,060

Schedule of Deferred Income



	January 28, 2017			January 30, 2016
Deferred income:
Net deferred revenue	$	93,148		$	75,541
Deferred cost of goods sold	(25,024		)	(21,568		)
Deferred income	$	68,124		$	53,973

Schedule of Other Non-current Liabilities



	January 28, 2017		January 30, 2016
Other non-current liabilities:
Technology license obligations	$	14,949	$	12,461
Long-term accrued employee compensation	4,075		6,078
Deferred tax liabilities	38,777		1,098
Other	6,136		7,326
Other non-current liabilities	$	63,937	$	26,963

Schedule of Changes in Accumulated Other Comprehensive Income (Loss)

The changes in accumulated other comprehensive income (loss) by components are presented in the following tables (in thousands):



	Unrealized Gain (Loss) on Marketable Securities			Unrealized Loss on Auction Rate Securities			Unrealized Gain (Loss) on Cash Flow Hedges			Total
Balance at January 31, 2015	$	3,768		$	(2,274	)	$	(1,186	)	$	308
Other comprehensive income (loss) before reclassifications	(3,838		)	—			1,111			(2,727		)
Amounts reclassified from accumulated other comprehensive income (loss)	(586		)	2,274			(64		)	1,624
Net current-period other comprehensive income (loss), net of tax	(4,424		)	2,274			1,047			(1,103		)
Balance at January 30, 2016	(656		)	—			(139		)	(795		)
Other comprehensive income before reclassifications	1,766			—			1,496			3,262
Amounts reclassified from accumulated other comprehensive income	(1,911		)	—			(533		)	(2,444		)
Net current-period other comprehensive income (loss), net of tax	(145		)	—			963			818
Balance at January 28, 2017	$	(801	)	$	—		$	824		$	23

Schedule of Amounts Reclassified from Accumulated Other Comprehensive Income (Loss)

The amounts reclassified from accumulated other comprehensive income (loss) by components are presented in the following table (in thousands):



	Year Ended
Affected Line Item in the Statement of Operations	January 28, 2017		January 30, 2016			January 31, 2015
Interest and other income, net:
Available-for-sale securities:
Marketable securities	$	1,911	$	586		$	1,245
Auction rate securities	—		(2,274		)	(512		)
Operating costs and expenses:
Cash flow hedges:
Research and development	467		48			(198		)
Selling and marketing	10		(1		)	(8		)
General and administrative	56		17			(12		)
Total	$	2,444	$	(1,624	)	$	515

Schedule of Interest and Other Income, Net



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Interest and other income, net:
Interest income	$	13,198		$	15,982		$	11,370
Net realized gain (loss) on investments	1,500			(1,473		)	1,449
Currency translation gain	1,746			6,655			1,871
Other income (loss)	946			(2,773		)	9,811
Interest expense	(368		)	(706		)	(1,167		)
	$	17,022		$	17,685		$	23,334

Schedule of Supplemental Cash Flow Information



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Supplemental cash flow information:
Cash paid for interest	$	363	$	703	$	1,167
Cash paid for income taxes, net	$	17,032	$	13,363	$	15,727
Non-Cash Investing and Financing Activities:
Purchase of intellectual property under license obligations	$	27,081	$	13,800	$	—
Unsettled trade receivable of available-for-sale securities	$	7,742	$	53,749	$	—
Unsettled trade payable of available-for-sale securities	$	15,371	$	—	$	—
Unpaid purchase of property and equipment at end of year	$	2,547	$	9,069	$	7,083
Unpaid repurchases of our common shares	$	1,499	$	—	$	—

Schedule of Computation of Basic and Diluted Net Income (Loss) Per Share

The computations of basic and diluted net income (loss) per share are presented in the following table (in thousands, except per share amounts):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Numerator:
Income (loss) from continuing operations	$	43,994		$	(769,155	)	$	483,787
Loss from discontinued operations	(22,843		)	(42,245		)	(48,441		)
Net income (loss)	$	21,151		$	(811,400	)	$	435,346
Denominator:
Weighted average shares — basic	509,738			510,945			511,089
Effect of dilutive securities:
Share-based awards	7,775			—			9,671
Weighted average shares — diluted	517,513			510,945			520,760
Income (loss) from continuing operations per share:
Basic	$	0.09		$	(1.51	)	$	0.95
Diluted	$	0.09		$	(1.51	)	$	0.93
Loss from discontinued operations per share:
Basic	$	(0.05	)	$	(0.08	)	$	(0.10	)
Diluted	$	(0.05	)	$	(0.08	)	$	(0.09	)
Net income (loss) per share:
Basic	$	0.04		$	(1.59	)	$	0.85
Diluted	$	0.04		$	(1.59	)	$	0.84

Schedule of Anti-dilutive Potential Shares

Anti-dilutive potential shares are presented in the following table (in thousands):



	Year Ended
	January 28, 2017	January 30, 2016	January 31, 2015
Weighted average shares outstanding:
Share-based awards	22,642	64,420	35,636

Derivative Financial Instruments (Tables)

12 Months Ended

Jan. 28, 2017

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Derivative Instruments

The notional amounts of outstanding forward contracts were as follows (in thousands):



	Buy Contracts
	January 28, 2017		January 30, 2016
Israeli shekel	$	63,523	$	19,082

Information about Gains (Losses) Associated with Derivative Financial Instruments

The following table provides information about gains (losses) associated with our derivative financial instruments (in thousands):



	Location of Gains (Losses) in Statement of Operations	Amount of Gains (Losses) in Statement of Operations for the Year Ended
	Location of Gains (Losses) in Statement of Operations	January 28, 2017		January 30, 2016			January 31, 2015
Derivatives designated as cash flow hedges:
Forward contracts:	Research and development	$	737	$	(390	)	$	(1,930	)
	Selling and marketing	15		(5		)	(24		)
	General and administrative	86		(26		)	(157		)
		$	838	$	(421	)	$	(2,111	)

- Definition

Tabular disclosure of pertinent information about a derivative or group of derivatives on a disaggregated basis, such as for individual instruments, or small groups of similar instruments. May include a combination of the type of instrument, risks being hedged, notional amount, hedge designation, related hedged item, inception date, maturity date, or other relevant item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41641-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41678-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41638-113959

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579240-113959

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41620-113959

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Fair Value Measurements (Tables)

12 Months Ended

Jan. 28, 2017

Fair Value Disclosures [Abstract]

Fair Value, Assets and Liabilities Measured on Recurring Basis



	Fair Value Measurements at January 28, 2017
	Level 1		Level 2		Level 3		Total
Items measured at fair value on a recurring basis:
Assets
Cash equivalents:
Money market funds	$	36,122	$	—	$	—	$	36,122
Time deposits	—		67,000		—		67,000
U.S. government and agency debt	17,497		—		—		17,497
Corporate debt securities	—		31,280		—		31,280
Foreign government and agency debt	—		1,500		—		1,500
Municipal debt securities	—		8,740		—		8,740
Short-term investments:
U.S. government and agency debt	185,387		—		—		185,387
Corporate debt securities	—		432,108		—		432,108
Asset backed securities	—		45,527		—		45,527
Foreign government and agency debt	—		13,375		—		13,375
Municipal debt securities	—		27,871		—		27,871
Time deposits	—		150,000		—		150,000
Prepaid expenses and other current assets:
Foreign currency forward contracts	—		735		—		735
Long-term investments:
Auction rate securities	—		—		4,615		4,615
Other non-current assets:
Severance pay fund	—		736		—		736
Total assets	$	239,006	$	778,872	$	4,615	$	1,022,493
Liabilities
Accrued liabilities:
Foreign currency forward contracts	$	—	$	58	$	—	$	58



	Fair Value Measurements at January 30, 2016
	Level 1		Level 2		Level 3		Total
Items measured at fair value on a recurring basis:
Assets
Cash equivalents:
Money market funds	$	160,400	$	—	$	—	$	160,400
Time deposits	—		209,405		—		209,405
U.S. government and agency debt	184,374		—		—		184,374
Corporate debt securities	—		54,689		—		54,689
Short-term investments:
U.S. government and agency debt	317,405		—		—		317,405
Corporate debt securities	—		557,821		—		557,821
Asset backed securities	—		76,736		—		76,736
Foreign government and agency debt	—		21,358		—		21,358
Municipal debt securities	—		31,249		—		31,249
Prepaid expenses and other current assets:
Foreign currency forward contracts	—		30		—		30
Long-term investments:
Auction rate securities	—		—		11,296		11,296
Other non-current assets:
Severance pay fund	—		678		—		678
Total assets	$	662,179	$	951,966	$	11,296	$	1,625,441
Liabilities
Accrued liabilities:
Foreign currency forward contracts	$	—	$	195	$	—	$	195

Summary of Change in Fair Values for Level Three Assets

The following table summarizes the change in fair values for Level 3 assets for the years ended January 28, 2017 and January 30, 2016 (in thousands):



	Level 3
Changes in fair value during the year (pre-tax):
Balance at January 31, 2015	$	10,226
Impairment loss	(1,204		)
Unrealized gain included in accumulated other comprehensive income	2,274
Balance at January 30, 2016	11,296
Sales, redemption and settlement	(6,681		)
Unrealized gain included in accumulated other comprehensive income	—
Balance at January 28, 2017	$	4,615

Goodwill and Acquired Intangible Assets, Net (Tables)

12 Months Ended

Jan. 28, 2017

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Finite-Lived Intangible Assets by Major Class

The carrying amounts of acquired intangible assets are as follows (in thousands):



		January 28, 2017							January 30, 2016
	Range of Useful Lives	Gross Carrying Amounts		Accumulated Amortization and Write-Offs			Net Carrying Amounts		Gross Carrying Amounts		Accumulated Amortization and Write-Offs			Net Carrying Amounts
Purchased and core technology	4 - 8 years	$	25,798	$	(22,227	)	$	3,571	$	25,798	$	(17,950	)	$	7,848
Customer intangibles	5 - 7 years	24,700		(24,700		)	—		24,700		(20,601		)	4,099
Total acquired intangible assets from continuing operations, net		$	50,498	$	(46,927	)	$	3,571	$	50,498	$	(38,551	)	$	11,947

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense of Identified Intangibles Excluding IPR&D

Based on the identified intangible assets recorded at January 28, 2017, the future amortization expense of identified intangibles for the next five fiscal years is as follows (in thousands):



Fiscal Year
2018	$	3,571
2019 and thereafter	—
	$	3,571

Restructuring and Other Related Charges (Tables)

12 Months Ended

Jan. 28, 2017

Restructuring and Related Activities [Abstract]

Summary of Restructuring and Other Related Charges

The following table provides a summary of restructuring and other related charges as presented in the Consolidated Statements of Operations (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Cost of goods sold	$	—	$	10,292	$	—
Restructuring and other related charges	105,186		53,251		10,438
Write-off of acquired intangible assets	—		—		3,386
	$	105,186	$	63,543	$	13,824

The following table presents details of charges recorded by the Company related to the restructuring actions described below (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016		January 31, 2015
Severance and related costs	$	41,035		$	43,926	$	5,181
Facilities and related costs	6,587			1,407		1,924
Loss on early contract termination	—			1,644		3,230
Other exit-related costs	5,452			534		86
	53,074			47,511		10,421
Release of reserves:
Severance	(86		)	—		—
Other exit-related costs	(383		)	—		—

Impairment and write-off of assets:
Prepaid deposit	45,000			—		—
Inventory	—			8,046		—
Technology licenses	629			1,250		—
Equipment and other	6,952			6,736		17
Acquired intangible asset	—			—		3,386
	$	105,186		$	63,543	$	13,824

Reconciliation of Beginning and Ending Restructuring Liability Balances by Major Type of Costs

The following table sets forth a reconciliation of the beginning and ending restructuring liability balances by each major type of costs associated with the restructuring charges (in thousands):



	November 2016 Restructuring									Mobile & Other Prior Restructuring
	Severance and related costs			Facilities and related costs			Other exit-related costs			Severance and related costs			Facilities and related costs			Other exit-related costs			Total
Balance at January 31, 2015	$	—		$	—		$	—		$	—		$	1,339		$	3,230		$	4,569
Cost reduction charges	—			—			—			43,926			1,407			2,178			47,511
Cash payments	—			—			—			(42,741		)	(1,567		)	(3,764		)	(48,072		)
Exchange rate adjustment	—			—			—			(30		)	(106		)	—			(136		)
Balance at January 30, 2016	—			—			—			1,155			1,043			1,644			3,842
Cost reduction charges	41,020			1,872			5,452			15			4,715			—			53,074
Cash payments	(24,065		)	(110		)	(829		)	(1,082		)	(5,112		)	(1,261		)	(32,459		)
Release of reserves	—			—			—			(86		)	—			(383		)	(469		)
Exchange rate adjustment	45			1			2			(2		)	65			—			111
Balance at January 28, 2017	17,000			1,763			4,625			—			711			—			24,099
Less: non-current portion	—			(949		)	—			—			—			—			(949		)
Current portion	$	17,000		$	814		$	4,625		$	—		$	711		$	—		$	23,150

Income Taxes (Tables)

12 Months Ended

Jan. 28, 2017

Income Tax Disclosure [Abstract]

Schedule of US and non US Components of Income Before Income Tax Expense (Benefit)

The U.S. and non-U.S. components of income (loss) before income taxes of continuing operations consist of the following (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016			January 31, 2015
U.S. operations	$	30,889	$	32,433		$	30,607
Non-U.S. operations	86,127		(790,253		)	449,103
	$	117,016	$	(757,820	)	$	479,710

Schedule of Provision (Benefit) for Income Taxes

The provision (benefit) for income taxes consists of the following (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Current income tax provision (benefit):
Federal	$	8,289		$	10,482		$	8,826
State	180			83			(161		)
Foreign	19,916			(5,326		)	171
Total current income tax provision (benefit)	28,385			5,239			8,836
Deferred income tax provision (benefit):
Federal	(5,062		)	(4,355		)	(1,775		)
State	(12		)	580			16
Foreign	49,711			9,871			(11,154		)
Total deferred income tax provision (benefit)	44,637			6,096			(12,913		)
Total provision (benefit) for income taxes	$	73,022		$	11,335		$	(4,077	)

Schedule of Deferred Tax Assets and Liabilities

Deferred tax assets consist of the following (in thousands):



	January 28, 2017			January 30, 2016
Deferred tax assets:
Federal and California research and other tax credits	$	450,503		$	414,662
Reserves and accruals	35,887			35,200
Share-based compensation	3,733			4,476
Net operating losses	5,361			11,055
Gross deferred tax assets	495,484			465,393
Valuation allowance	(456,541		)	(424,914		)
Total deferred tax assets	38,943			40,479
Total deferred tax liabilities	(51,112		)	(7,073		)
Net deferred tax assets (liabilities)	$	(12,169	)	$	33,406

Reconciliation Between the Provision (Benefit) for Income Taxes at the Statutory Rate and the Effective Tax Rate

For purposes of the reconciliation between the provision (benefit) for income taxes at the statutory rate and the effective tax rate, a notional U.S. 35% rate is applied as follows:



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Provision at U.S. notional statutory rate	35.0	%	35.0	%	35.0	%
Difference in U.S. and non-U.S. tax rates	(23.7	)	(37.1	)	(35.1	)
Benefits from utilization of general business credits	(35.8	)	5.2		(10.8	)
Change in valuation allowance	30.6		(4.3	)	9.5
Withholding taxes	42.8		—		—
Tax effects of global restructuring	14.3		—		—
Other	(0.8	)	(0.3	)	0.5
Effective tax rate	62.4	%	(1.5	)%	(0.9	)%

Unrecognized Tax Benefits Reconciliation

The following table reflects changes in the unrecognized tax benefits (in thousands):



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Unrecognized tax benefits as of the beginning of the period	$	29,139		$	45,197		$	51,682
Increases related to prior year tax positions	2,080			304			976
Decreases related to prior year tax positions	—			(4,334		)	(386		)
Increases related to current year tax positions	2,363			4,237			5,356
Settlements	—			(704		)	—
Lapse in the statute of limitations	(6,576		)	(9,739		)	(10,691		)
Foreign exchange gain	(3,213		)	(5,822		)	(1,740		)
Gross amounts of unrecognized tax benefits as of the end of the period	$	23,793		$	29,139		$	45,197

Commitments and Contingencies (Tables)

12 Months Ended

Jan. 28, 2017

Commitments and Contingencies Disclosure [Abstract]

Future Minimum Lease Payments, Net of Estimated Sublease Income under Operating and Capital Leases

Future minimum lease payments, net of estimated sublease income, and payments under technology license obligations as of January 28, 2017, are presented in the following tables (in thousands):



Fiscal Year	Minimum Operating Leases Payments
2018	$	37,167
2019	27,004
2020	16,708
2021	3,767
2022	610
Thereafter	2,147
Total future minimum lease payments	$	87,403

Future Minimum Lease Payments Under Technology License Obligations



Fiscal Year	Technology License Obligations
2018	$	23,180
2019	7,025
2020 and thereafter	7,025
Total future minimum lease payments	$	37,230
Less: amount representing interest	(170		)
Present value of future minimum payments	37,060
Less: current portion	(22,111		)
Non-current portion	$	14,949

Shareholders’ Equity (Tables)

12 Months Ended

Jan. 28, 2017

Equity [Abstract]

Schedule of Stock Option Activity

Stock option activity under the Company’s stock option and stock incentive plans is included in the following table (in thousands, except for per share amounts):



	Time-Based Options				Market-Based Options				Total
	Number of Shares		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price
Balance at February 1, 2014	49,156		$	13.40	2,623		$	15.43	51,779		$	13.51
Granted	6,365		$	15.33	—		—		6,365		$	15.33
Exercised	(3,732	)	$	10.19	—		—		(3,732	)	$	10.19
Canceled/Forfeited	(4,649	)	$	14.66	(391	)	$	15.43	(5,040	)	$	14.72
Balance at January 31, 2015	47,140		$	13.79	2,232		$	15.43	49,372		$	13.88
Granted	6,170		$	14.13	—		—		6,170		$	14.13
Exercised	(2,225	)	$	9.79	—		—		(2,225	)	$	9.79
Canceled/Forfeited	(10,211	)	$	15.68	(76	)	$	15.43	(10,287	)	$	15.68
Balance at January 30, 2016	40,874		$	13.59	2,156		$	15.43	43,030		$	13.68
Granted	2,104		$	9.99	—		—		2,104		$	9.99
Exercised	(5,558	)	$	10.35	—		—		(5,558	)	$	10.35
Canceled/Forfeited	(12,324	)	$	16.44	(2,156	)	$	15.43	(14,480	)	$	16.29
Balance at January 28, 2017	25,096		$	12.61	—				25,096		$	12.61
Vested or expected to vest at January 28, 2017	24,253		$	12.57

Schedule of Outstanding Options and Exercisable Options Information, by Range of Exercise Prices

Outstanding options and exercisable options information by range of exercise prices as of January 28, 2017 was as follows:



				Outstanding Options				Exercisable Options
Range of Exercise Prices				Number of Shares (in Thousands)	Weighted Average Remaining Contractual Term (in Years)	Weighted Average Exercise Price		Number of Shares (in Thousands)	Weighted Average Exercise Price
$	5.70	$	10.47	3,842	4.84	$	8.11	2,214	$	6.94
$	10.76	$	10.76	7,004	6.16	$	10.76	4,344	$	10.76
$	10.80	$	14.35	6,047	5.79	$	13.13	2,630	$	11.72
$	14.45	$	15.87	5,540	5.82	$	15.40	2,385	$	15.24
$	15.91	$	21.62	2,663	1.19	$	16.95	2,599	$	16.96
Total				25,096	5.27	$	12.61	14,172	$	12.23

Schedule of Nonvested Share Activity

Activity related to the non-vested portion of the restricted stock units is included in the following table (in thousands, except for share prices):



	Time-Based				Performance-Based					Market-Based					Total
	Number of Shares		Weighted Average Grant Date Fair Value		Number of Shares			Weighted Average Grant Date Fair Value		Number of Shares			Weighted Average Grant Date Fair Value		Number of Shares		Weighted Average Grant Date Fair Value
Balance at February 1, 2014	11,254		$	14.14	100			$	10.52						11,354		$	14.11
Granted	5,534		$	15.20	1,277		*	$	14.98						6,811		$	15.16
Vested	(5,938	)	$	13.96	(3	)		$	10.52						(5,941	)	$	13.96
Canceled/Forfeited	(1,102	)	$	14.32	(120	)		$	11.23						(1,222	)	$	14.02
Balance at January 31, 2015	9,748		$	14.84	1,254			$	14.99						11,002		$	14.85
Granted	5,689		$	12.88	669		*	$	14.08	407			$	12.24	6,765		$	12.96
Vested	(5,139	)	$	15.06	(658	)		$	15.15	—			$	—	(5,797	)	$	15.07
Canceled/Forfeited	(1,955	)	$	13.99	(288	)		$	14.39	(54	)		$	12.24	(2,297	)	$	14.00
Balance at January 30, 2016	8,343		$	13.57	977			$	14.43	353			$	12.24	9,673		$	13.61
Granted	9,139		$	9.83	366		*	$	13.91	612		*	$	11.94	10,117		$	10.11
Vested	(5,490	)	$	13.95	(155	)		$	14.15	—			—		(5,645	)	$	13.95
Canceled/Forfeited	(2,067	)	$	10.69	(875	)		$	14.45	(406	)		$	12.39	(3,348	)	$	11.88
Balance at January 28, 2017	9,925		$	10.52	313			$	13.91	559			$	11.80	10,797		$	10.69


*	Amounts represent the target number of restricted stock units at grant date. For awards granted to our executive officers, up to 200% of the target restricted stock units may vest if the maximum level for performance goals is achieved.

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

The following table presents details of share-based compensation expenses by functional line item (in thousands):



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Continuing operations:
Cost of goods sold	$	8,334	$	7,787	$	7,972
Research and development	78,136		92,054		89,131
Selling and marketing	10,243		10,242		10,623
General and administrative	8,047		15,878		23,292
Share-based compensation - continuing operations	$	104,760	$	125,961	$	131,018
Discontinued operations:
Cost of goods sold	187		129		—
Research and development	8,306		6,738		5,301
Selling and marketing	649		864		846
General and administrative	68		87		81
Share-based compensation - discontinued operations	9,210		7,818		6,228
Total share-based compensation	$	113,970	$	133,779	$	137,246

Weighted Average Assumptions Used to Calculate Fair Value Awards



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Employee Stock Purchase Plan:
Estimated fair value	$	3.83		$	3.24		$	4.10
Expected volatility	39		%	41		%	30		%
Expected term (in years)	1.2			1.3			1.3
Risk-free interest rate	0.7		%	0.6		%	0.3		%
Expected dividend yield	1.9		%	2.4		%	1.6		%



	Year Ended
	January 28, 2017		January 30, 2016
Total Shareholder Return Awards:
Expected term (in years)	2.9		2.0
Expected volatility	36	%	27	%
Average correlation coefficient of peer companies	0.5		0.4
Risk-free interest rate	0.9	%	0.5	%
Expected dividend yield	2.1	%	1.7	%



	Year Ended
	January 28, 2017			January 30, 2016			January 31, 2015
Time-based Stock Options:
Weighted average fair value	$	2.92		$	3.93		$	4.35
Expected volatility	40		%	34		%	35		%
Expected term (in years)	5.2			5.4			5.0
Risk-free interest rate	1.3		%	1.6		%	1.6		%
Expected dividend yield	2.5		%	1.8		%	1.6		%

Segment and Geographic Information (Tables)

12 Months Ended

Jan. 28, 2017

Segment Reporting [Abstract]

Net Revenue and Long-Lived Asset Information Based on Geographic Region



	Year Ended
	January 28, 2017		January 30, 2016		January 31, 2015
Net Revenue:
United States	$	51,416	$	60,119	$	61,470
China	1,239,931		1,509,244		2,171,299
Thailand	113,778		189,299		294,706
Malaysia	286,267		302,953		377,903
Philippines	283,345		211,602		254,381
Others	342,937		375,999		477,447
	$	2,317,674	$	2,649,216	$	3,637,206



	January 28, 2017		January 30, 2016
Property and equipment, net:
China	$	16,484	$	22,294
Israel	12,133		15,069
Singapore	54,054		68,212
United States	147,552		173,158
Others	13,174		18,045
	$	243,397	$	296,778

The Company and its Significant Accounting Policies - Discontinued Operations (Details)	12 Months Ended
	Jan. 28, 2017 business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of businesses to be disposed of	2
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of businesses to be disposed of	2

The Company and its Significant Accounting Policies - Concentration of Credit Risk and Significant Customers (Details) - Customer Concentration Risk - Accounts Receivable	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016
Customer A
Concentration Risk [Line Items]
Concentration of risk percentage	14.00%	13.00%
Customer B
Concentration Risk [Line Items]
Concentration of risk percentage	13.00%	11.00%
Customer C
Concentration Risk [Line Items]
Concentration of risk percentage	11.00%

The Company and its Significant Accounting Policies - Schedule of Net Revenue Attributable to Significant Customers (Details) - Net Revenue - Customer Concentration Risk	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Western Digital
Concentration Risk [Line Items]
Concentration of risk percentage	21.00%	19.00%	20.00%
Toshiba
Concentration Risk [Line Items]
Concentration of risk percentage	13.00%
Seagate
Concentration Risk [Line Items]
Concentration of risk percentage	9.00%	14.00%	13.00%
Wintech
Concentration Risk [Line Items]
Concentration of risk percentage	10.00%		11.00%

The Company and its Significant Accounting Policies - Property and Equipment, Net (Details)	12 Months Ended
	Jan. 28, 2017
Machinery and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	3 years
Machinery and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	7 years
Computer software \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	3 years
Computer software \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	4 years
Furniture and fixtures \| Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	3 years
Furniture and fixtures \| Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	4 years
Buildings
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	30 years
Building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives (in years)	15 years

The Company and its Significant Accounting Policies - Goodwill (Details)	12 Months Ended
	Jan. 28, 2017 component
Accounting Policies [Abstract]
Number of components	2

The Company and its Significant Accounting Policies - Revenue Recognition (Details)	12 Months Ended
	Jan. 28, 2017
Minimum
Inventory [Line Items]
Inventory turnover period (in days)	60 days
Maximum
Inventory [Line Items]
Inventory turnover period (in days)	90 days

The Company and its Significant Accounting Policies - Advertising Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Accounting Policies [Abstract]
Advertising costs	$ 0.5	$ 5.1	$ 5.6

The Company and its Significant Accounting Policies - Share-Based Compensation (Details)	12 Months Ended
	Jan. 28, 2017 group
Employee group
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of groups used in calculating assumptions for stock option exercises and pre-vesting terminations of stock options	2
Employee/non-employee group
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of groups used in calculating assumptions for stock option exercises and pre-vesting terminations of stock options	1
Stock Purchase Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	2 years

The Company and its Significant Accounting Policies - Warranty (Details)	12 Months Ended
	Jan. 28, 2017
Accounting Policies [Abstract]
Standard warranty period	90 days
Extended warranty period	1 year

Discontinued Operations - Additional Information (Details) $ in Thousands	1 Months Ended	12 Months Ended
	Nov. 30, 2016 USD ($) position	Jan. 28, 2017 USD ($) business	Jan. 30, 2016 USD ($)	Jan. 31, 2015 USD ($)
Business Acquisition [Line Items]
Number of positions to be eliminated \| position	900
Number of businesses to be disposed of \| business		2
Share-based compensation		$ 113,970	$ 133,779	$ 137,246
Disposal Group, Not Discontinued Operations \| Operating Expenses
Business Acquisition [Line Items]
Effect on future earnings	$ 60,000
Disposal Group, Not Discontinued Operations \| Revenues
Business Acquisition [Line Items]
Effect on future earnings	$ (100,000)
Discontinued Operations
Business Acquisition [Line Items]
Number of businesses to be disposed of \| business		2
Share-based compensation		$ 9,200	7,800	6,200
Provision for income taxes		$ 977	$ 1,011	$ 884

Discontinued Operations - Current Assets and Liabilities Held for Sale (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Other assets held for sale
Total assets of the disposal group classified as held for sale	$ 45,846	$ 45,095
Current liabilities held for sale:
Total liabilities of the disposal group classified as held for sale	1,670	1,749
Discontinued Operations
Current assets held for sale:
Inventory	8,154	9,059
Property and equipment, net	2,898	2,762
Goodwill	26,532	26,532
Acquired intangible assets, net	3,799	6,063
Other	1,490	679
Current assets held for sale for discontinued operations	42,873	45,095
Other assets held for sale
Property and equipment, net	2,973	0
Total assets of the disposal group classified as held for sale	45,846	45,095
Current liabilities held for sale:
Deferred Income	1,670	1,749
Total liabilities of the disposal group classified as held for sale	$ 1,670	$ 1,749

Discontinued Operations - Components of Results of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Operating costs and expenses:
Net loss from discontinued operations	$ (22,843)	$ (42,245)	$ (48,441)
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net Revenue	98,755	76,612	69,757
Operating costs and expenses:
Cost of goods sold	60,799	52,219	44,281
Research and development	53,784	59,524	67,263
Selling and marketing	4,750	4,684	4,325
General and administrative	963	769	795
Amortization of acquired intangible assets	325	650	650
Total operating costs and expenses	120,621	117,846	117,314
Loss from discontinued operations before income taxes	(21,866)	(41,234)	(47,557)
Provision for income taxes	977	1,011	884
Net loss from discontinued operations	$ (22,843)	$ (42,245)	$ (48,441)

Investments - Summary of Investments (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Available-for-sale:
Amortized Cost	$ 859,684	$ 1,016,520
Estimated Fair Value	858,883	1,015,865
Held-to-Maturity:
Amortized Cost	859,684	1,016,520
Gross Unrealized Gains	404	958
Gross Unrealized Losses	(1,205)	(1,613)
Estimated Fair Value	858,883	1,015,865
Short-term Investments
Held-to-Maturity:
Amortized Cost	855,069	1,005,224
Gross Unrealized Gains	404	958
Gross Unrealized Losses	(1,205)	(1,613)
Estimated Fair Value	854,268	1,004,569
Corporate debt securities
Available-for-sale:
Amortized Cost	432,603	558,337
Gross Unrealized Gains	281	766
Gross Unrealized Losses	(776)	(1,282)
Estimated Fair Value	432,108	557,821
U.S. government and agency debt
Available-for-sale:
Amortized Cost	185,584	317,595
Gross Unrealized Gains	86	64
Gross Unrealized Losses	(283)	(254)
Estimated Fair Value	185,387	317,405
Asset backed securities
Available-for-sale:
Amortized Cost	45,541	76,711
Gross Unrealized Gains	33	81
Gross Unrealized Losses	(47)	(56)
Estimated Fair Value	45,527	76,736
Foreign government and agency debt
Available-for-sale:
Amortized Cost	13,425	21,370
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(50)	(14)
Estimated Fair Value	13,375	21,358
Municipal debt securities
Available-for-sale:
Amortized Cost	27,916	31,211
Gross Unrealized Gains	4	45
Gross Unrealized Losses	(49)	(7)
Estimated Fair Value	27,871	31,249
Time deposits
Held-to-Maturity:
Amortized Cost	150,000
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	150,000
Long-term investments
Held-to-Maturity:
Amortized Cost	4,615	11,296
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	4,615	11,296
Auction rate securities
Available-for-sale:
Amortized Cost	4,615	11,296
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 4,615	$ 11,296

Investments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Gain (Loss) on Investments [Line Items]
Auction rate securities, aggregate par value	$ 5,000
Impairment loss	0	$ 1,204	$ 0
Net gain from sale of securities	2,047	$ 1,654	$ 1,618
Long-term investments
Gain (Loss) on Investments [Line Items]
Impairment loss	400
Auction rate securities
Gain (Loss) on Investments [Line Items]
Auction rate securities sold, aggregate par value	7,500
Proceeds from sale of auction rate securities	6,900
Sold security, at carrying value	6,700
Net gain from sale of securities	$ 200

Investments - Gross Realized Gains and Losses on Sales of Available-for-Sale Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$ 2,047	$ 1,654	$ 1,618
Gross realized losses	(547)	(1,923)	(169)
Impairment loss	0	(1,204)	0
Total net realized gains (losses)	$ 1,500	$ (1,473)	$ 1,449

Investments - Contractual Maturities of Available for Sale Securities (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Amortized Cost
Due in one year or less	$ 423,151	$ 304,117
Due between one and five years	423,669	689,847
Due over five years	12,864	22,556
Amortized Cost	859,684	1,016,520
Estimated Fair Value
Due in one year or less	423,058	304,035
Due between one and five years	422,995	689,279
Due over five years	12,830	22,551
Estimated Fair Value	$ 858,883	$ 1,015,865

Investments - Summary of Investments Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Fair Value
Less than 12 months	$ 339,525	$ 612,510
12 months or more	18,810	15,954
Total	358,335	628,464
Unrealized Loss
Less than 12 months	(1,176)	(1,566)
12 months or more	(29)	(47)
Total	(1,205)	(1,613)
Corporate debt securities
Fair Value
Less than 12 months	199,382	283,138
12 months or more	16,063	14,383
Total	215,445	297,521
Unrealized Loss
Less than 12 months	(751)	(1,237)
12 months or more	(25)	(45)
Total	(776)	(1,282)
U.S. government and agency debt
Fair Value
Less than 12 months	94,064	263,325
12 months or more	0	0
Total	94,064	263,325
Unrealized Loss
Less than 12 months	(283)	(254)
12 months or more	0	0
Total	(283)	(254)
Asset backed securities
Fair Value
Less than 12 months	16,754	46,646
12 months or more	0	0
Total	16,754	46,646
Unrealized Loss
Less than 12 months	(47)	(56)
12 months or more	0	0
Total	(47)	(56)
Foreign government and agency debt
Fair Value
Less than 12 months	11,875	16,458
12 months or more	1,499	0
Total	13,374	16,458
Unrealized Loss
Less than 12 months	(48)	(14)
12 months or more	(2)	0
Total	(50)	(14)
Municipal debt securities
Fair Value
Less than 12 months	17,450	2,943
12 months or more	1,248	1,571
Total	18,698	4,514
Unrealized Loss
Less than 12 months	(47)	(5)
12 months or more	(2)	(2)
Total	$ (49)	$ (7)

Supplemental Financial Information - Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Feb. 01, 2014
Cash and cash equivalents:
Cash	$ 651,953	$ 669,312
Cash equivalents:
Time deposits	67,000	209,405
U.S. government and agency debt	17,497	184,374
Money market funds	36,122	160,400
Corporate debt securities	31,280	54,689
Municipal debt securities	8,740	0
Foreign government and agency debt	1,500	0
Cash and cash equivalents	$ 814,092	$ 1,278,180	$ 1,210,977	$ 965,750

Supplemental Financial Information - Provision for Sales Return and Allowance (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Provision for sales returns and allowances:
Sales returns	$ 470	$ 1,873
Doubtful accounts	914	889
Provision for sales returns and allowances	$ 1,384	$ 2,762

Supplemental Financial Information - Inventories (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Inventories:
Work-in-process	$ 110,083	$ 125,800
Finished goods	61,886	75,158
Inventories	171,969	200,958
Inventory held at third-party logistics providers	$ 26,500	$ 21,000

Supplemental Financial Information - Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,009,244	$ 1,005,077
Less: Accumulated depreciation	(765,847)	(708,299)
Property and equipment, net	243,397	296,778
Depreciation expense	82,400	73,800	$ 78,300
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	578,248	575,954
Buildings and building improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	194,290	194,247
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	99,186	102,840
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	53,373	53,373
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	49,004	50,192
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	23,903	27,118
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 11,240	$ 1,353

Supplemental Financial Information - Other Non-current Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Other non-current assets:
Technology and other licenses	$ 53,254	$ 48,091
Deferred tax assets	26,608	34,505
Investments in privately-held companies	5,787	5,804
Prepaid land use rights	12,810	13,123
Deposits	3,756	51,512
Other	11,109	10,996
Other non-current assets	113,324	164,031
Investment impairment	45,000
Finite-Lived Intangible Assets [Line Items]
Amortization and write-off of acquired intangible assets	8,376	10,098	$ 15,747
Technology and Other Licenses
Finite-Lived Intangible Assets [Line Items]
Amortization and write-off of acquired intangible assets	$ 25,500	$ 26,400	$ 27,900

Supplemental Financial Information - Accrued Liabilities (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Accrued liabilities:
Accrued rebates	$ 26,095	$ 41,320
Restructuring liability	23,150	3,842
Accrued royalties	17,349	16,217
Technology license obligations	21,905	17,985
Accrued legal expense	5,127	9,761
Other	49,865	42,935
Accrued liabilities	$ 143,491	$ 132,060

Supplemental Financial Information - Deferred Income (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Deferred income:
Net deferred revenue	$ 93,148	$ 75,541
Deferred cost of goods sold	(25,024)	(21,568)
Deferred income	$ 68,124	$ 53,973

- Definition

The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

+ References + Details

Supplemental Financial Information - Other Non-current Liabilities (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Other non-current liabilities:
Technology license obligations	$ 14,949	$ 12,461
Long-term accrued employee compensation	4,075	6,078
Deferred tax liabilities	38,777	1,098
Other	6,136	7,326
Other non-current liabilities	$ 63,937	$ 26,963

Supplemental Financial Information - Changes in Accumulated Other Comprehensive Income (Loss) by Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 4,140,123	$ 5,146,089	$ 4,675,910
Other comprehensive income (loss) before reclassifications	3,262	(2,727)
Amounts reclassified from accumulated other comprehensive income (loss)	(2,444)	1,624
Other comprehensive income (loss), net of tax	818	(1,103)	(289)
Balance at end of period	4,027,651	4,140,123	5,146,089
Unrealized Gain (Loss) on Marketable Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(656)	3,768
Other comprehensive income (loss) before reclassifications	1,766	(3,838)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,911)	(586)
Other comprehensive income (loss), net of tax	(145)	(4,424)
Balance at end of period	(801)	(656)	3,768
Unrealized Loss on Auction Rate Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	0	(2,274)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	2,274
Other comprehensive income (loss), net of tax	0	2,274
Balance at end of period	0	0	(2,274)
Unrealized Gain (Loss) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(139)	(1,186)
Other comprehensive income (loss) before reclassifications	1,496	1,111
Amounts reclassified from accumulated other comprehensive income (loss)	(533)	(64)
Other comprehensive income (loss), net of tax	963	1,047
Balance at end of period	824	(139)	(1,186)
Total
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(795)	308	597
Other comprehensive income (loss), net of tax	818	(1,103)	(289)
Balance at end of period	$ 23	$ (795)	$ 308

Supplemental Financial Information - Amounts Reclassified from Accumulated Other Comprehensive Income (Loss) by Components (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest and other income, net	$ 17,022	$ 17,685	$ 23,334
Research and development	(831,398)	(994,733)	(1,091,547)
Selling and marketing	(115,817)	(124,096)	(139,627)
General and administrative	(127,376)	(145,359)	(124,046)
Net Income (loss)	21,151	(811,400)	435,346
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Income (loss)	2,444	(1,624)	515
Reclassification out of Accumulated Other Comprehensive Income \| Marketable securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest and other income, net	1,911	586	1,245
Reclassification out of Accumulated Other Comprehensive Income \| Auction rate securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest and other income, net	0	(2,274)	(512)
Reclassification out of Accumulated Other Comprehensive Income \| Cash flow hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Research and development	467	48	(198)
Selling and marketing	10	(1)	(8)
General and administrative	$ 56	$ 17	$ (12)

Supplemental Financial Information - Interest and Other Income, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Interest and other income, net:
Interest income	$ 13,198	$ 15,982	$ 11,370
Net realized gain (loss) on investments	1,500	(1,473)	1,449
Currency translation gain	1,746	6,655	1,871
Other income (loss)	946	(2,773)	9,811
Interest expense	(368)	(706)	(1,167)
Interest and other income, net	$ 17,022	$ 17,685	$ 23,334

- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References + Details

Supplemental Financial Information - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Supplemental cash flow information:
Cash paid for interest	$ 363	$ 703	$ 1,167
Cash paid for income taxes, net	17,032	13,363	15,727
Non-Cash Investing and Financing Activities:
Purchase of intellectual property under license obligations	27,081	13,800	0
Unsettled trade receivable of available-for-sale securities	7,742	53,749	0
Unsettled trade payable of available-for-sale securities	15,371	0	0
Unpaid purchase of property and equipment at end of year	2,547	9,069	7,083
Unpaid repurchases of our common shares	$ 1,499	$ 0	$ 0

Supplemental Financial Information - Computations of Basic and Diluted Net Income (Loss) Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Numerator:
Income (loss) from continuing operations	$ 43,994	$ (769,155)	$ 483,787
Loss from discontinued operations	(22,843)	(42,245)	(48,441)
Net Income (loss)	$ 21,151	$ (811,400)	$ 435,346
Denominator:
Weighted average shares — basic	509,738	510,945	511,089
Effect of dilutive securities:
Share-based awards (in shares)	7,775	0	9,671
Weighted average shares — diluted	517,513	510,945	520,760
Income (loss) from continuing operations per share:
Basic (in usd per share)	$ 0.09	$ (1.51)	$ 0.95
Diluted (in usd per share)	0.09	(1.51)	0.93
Loss from discontinued operations per share:
Basic (in usd per share)	(0.05)	(0.08)	(0.10)
Diluted (in usd per share)	(0.05)	(0.08)	(0.09)
Net income (loss) per share:
Net Income (loss) per share basic (in usd per share)	0.04	(1.59)	0.85
Net Income (loss) per share diluted (in usd per share)	$ 0.04	$ (1.59)	$ 0.84

Supplemental Financial Information - Anti-dilutive Potential Shares (Details) - shares shares in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Weighted average shares outstanding:
Share-based awards (in shares)	22,642	64,420	35,636

Derivative Financial Instruments - Notional Amounts of Outstanding Foreign Currency Forward Contracts (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Foreign Exchange Buy Contracts \| Israeli shekel
Derivative [Line Items]
Derivative, notional amount	$ 63,523	$ 19,082

Derivative Financial Instruments - Information about Gains (Losses) Associated with Derivative Financial Instruments (Details) - Cash flow hedges - Foreign currency forward contracts - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gains (Losses) in Statement of Operations	$ 838	$ (421)	$ (2,111)
Research and development
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gains (Losses) in Statement of Operations	737	(390)	(1,930)
Selling and marketing
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gains (Losses) in Statement of Operations	15	(5)	(24)
General and administrative
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gains (Losses) in Statement of Operations	$ 86	$ (26)	$ (157)

Derivative Financial Instruments - Additional Information (Details) - USD ($)	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash flow hedges were terminated as a result of forecasted transactions that did not occur	$ 0
Not Designated as Hedging Instrument \| Foreign currency forward contracts \| Interest and other income, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Portion of gains (losses) excluded from the assessment of hedge effectiveness	$ (300,000)	$ (100,000)	$ 200,000

Fair Value Measurements - Assets and Liabilities that are Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Assets
Investments	$ 858,883	$ 1,015,865
Fair Value
Assets
Total assets	1,022,493	1,625,441
Fair Value \| Other non-current assets \| Severance pay fund
Assets
Other non-current assets	736	678
Fair Value \| Foreign currency forward contracts
Liabilities
Accrued liabilities	58	195
Fair Value \| Foreign currency forward contracts \| Prepaid expenses and other current assets
Assets
Prepaid expenses and other current assets	735	30
Fair Value \| Money market funds
Assets
Cash equivalents	36,122	160,400
Fair Value \| Time deposits
Assets
Cash equivalents	67,000	209,405
Fair Value \| Time deposits \| Short-term investments
Assets
Investments	150,000
Fair Value \| U.S. government and agency debt
Assets
Cash equivalents	17,497	184,374
Fair Value \| U.S. government and agency debt \| Short-term investments
Assets
Investments	185,387	317,405
Fair Value \| Corporate debt securities
Assets
Cash equivalents	31,280	54,689
Fair Value \| Corporate debt securities \| Short-term investments
Assets
Investments	432,108	557,821
Fair Value \| Asset backed securities \| Short-term investments
Assets
Investments	45,527	76,736
Fair Value \| Foreign government and agency debt
Assets
Cash equivalents	1,500
Fair Value \| Foreign government and agency debt \| Short-term investments
Assets
Investments	13,375	21,358
Fair Value \| Municipal debt securities
Assets
Cash equivalents	8,740
Fair Value \| Municipal debt securities \| Short-term investments
Assets
Investments	27,871	31,249
Fair Value \| Auction rate securities \| Long-term investments
Assets
Investments	4,615	11,296
Fair Value \| Level 1
Assets
Total assets	239,006	662,179
Fair Value \| Level 1 \| Other non-current assets \| Severance pay fund
Assets
Other non-current assets	0	0
Fair Value \| Level 1 \| Foreign currency forward contracts
Liabilities
Accrued liabilities	0	0
Fair Value \| Level 1 \| Foreign currency forward contracts \| Prepaid expenses and other current assets
Assets
Prepaid expenses and other current assets	0	0
Fair Value \| Level 1 \| Money market funds
Assets
Cash equivalents	36,122	160,400
Fair Value \| Level 1 \| Time deposits
Assets
Cash equivalents	0	0
Fair Value \| Level 1 \| Time deposits \| Short-term investments
Assets
Investments	0
Fair Value \| Level 1 \| U.S. government and agency debt
Assets
Cash equivalents	17,497	184,374
Fair Value \| Level 1 \| U.S. government and agency debt \| Short-term investments
Assets
Investments	185,387	317,405
Fair Value \| Level 1 \| Corporate debt securities
Assets
Cash equivalents	0	0
Fair Value \| Level 1 \| Corporate debt securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 1 \| Asset backed securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 1 \| Foreign government and agency debt
Assets
Cash equivalents	0
Fair Value \| Level 1 \| Foreign government and agency debt \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 1 \| Municipal debt securities
Assets
Cash equivalents	0
Fair Value \| Level 1 \| Municipal debt securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 1 \| Auction rate securities \| Long-term investments
Assets
Investments	0	0
Fair Value \| Level 2
Assets
Total assets	778,872	951,966
Fair Value \| Level 2 \| Other non-current assets \| Severance pay fund
Assets
Other non-current assets	736	678
Fair Value \| Level 2 \| Foreign currency forward contracts
Liabilities
Accrued liabilities	58	195
Fair Value \| Level 2 \| Foreign currency forward contracts \| Prepaid expenses and other current assets
Assets
Prepaid expenses and other current assets	735	30
Fair Value \| Level 2 \| Money market funds
Assets
Cash equivalents	0	0
Fair Value \| Level 2 \| Time deposits
Assets
Cash equivalents	67,000	209,405
Fair Value \| Level 2 \| Time deposits \| Short-term investments
Assets
Investments	150,000
Fair Value \| Level 2 \| U.S. government and agency debt
Assets
Cash equivalents	0	0
Fair Value \| Level 2 \| U.S. government and agency debt \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 2 \| Corporate debt securities
Assets
Cash equivalents	31,280	54,689
Fair Value \| Level 2 \| Corporate debt securities \| Short-term investments
Assets
Investments	432,108	557,821
Fair Value \| Level 2 \| Asset backed securities \| Short-term investments
Assets
Investments	45,527	76,736
Fair Value \| Level 2 \| Foreign government and agency debt
Assets
Cash equivalents	1,500
Fair Value \| Level 2 \| Foreign government and agency debt \| Short-term investments
Assets
Investments	13,375	21,358
Fair Value \| Level 2 \| Municipal debt securities
Assets
Cash equivalents	8,740
Fair Value \| Level 2 \| Municipal debt securities \| Short-term investments
Assets
Investments	27,871	31,249
Fair Value \| Level 2 \| Auction rate securities \| Long-term investments
Assets
Investments	0	0
Fair Value \| Level 3
Assets
Total assets	4,615	11,296
Fair Value \| Level 3 \| Other non-current assets \| Severance pay fund
Assets
Other non-current assets	0	0
Fair Value \| Level 3 \| Foreign currency forward contracts
Liabilities
Accrued liabilities	0	0
Fair Value \| Level 3 \| Foreign currency forward contracts \| Prepaid expenses and other current assets
Assets
Prepaid expenses and other current assets	0	0
Fair Value \| Level 3 \| Money market funds
Assets
Cash equivalents	0	0
Fair Value \| Level 3 \| Time deposits
Assets
Cash equivalents	0	0
Fair Value \| Level 3 \| Time deposits \| Short-term investments
Assets
Investments	0
Fair Value \| Level 3 \| U.S. government and agency debt
Assets
Cash equivalents	0	0
Fair Value \| Level 3 \| U.S. government and agency debt \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 3 \| Corporate debt securities
Assets
Cash equivalents	0	0
Fair Value \| Level 3 \| Corporate debt securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 3 \| Asset backed securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 3 \| Foreign government and agency debt
Assets
Cash equivalents	0
Fair Value \| Level 3 \| Foreign government and agency debt \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 3 \| Municipal debt securities
Assets
Cash equivalents	0
Fair Value \| Level 3 \| Municipal debt securities \| Short-term investments
Assets
Investments	0	0
Fair Value \| Level 3 \| Auction rate securities \| Long-term investments
Assets
Investments	$ 4,615	$ 11,296

Fair Value Measurements - Change in Fair Values for Level 3 Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 11,296	$ 10,226
Impairment loss		(1,204)
Sales, redemption and settlement	(6,681)
Unrealized gain included in accumulated other comprehensive income	0	2,274
Ending balance	$ 4,615	$ 11,296

Goodwill and Acquired Intangible Assets, Net - Additional Information (Details)	3 Months Ended	12 Months Ended
	Jan. 28, 2017 USD ($)	Jan. 28, 2017 USD ($) component segment	Jan. 30, 2016 USD ($)	Jan. 31, 2015 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill acquired		$ 0	$ 0
Goodwill written off		$ 0	$ 0
Number of components \| component		2
Number of operating segments \| segment		1
Number of reportable segments \| segment		1
Goodwill impairment	$ 0
IPR&D written off				$ 3,400,000

Goodwill and Acquired Intangible Assets, Net - Acquired Intangible Assets Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	$ 50,498	$ 50,498
Accumulated Amortization and Write-Offs	(46,927)	(38,551)
Net Carrying Amounts	3,571	11,947
Purchased and core technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	25,798	25,798
Accumulated Amortization and Write-Offs	(22,227)	(17,950)
Net Carrying Amounts	$ 3,571	7,848
Purchased and core technology \| Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Range of Useful Lives	4 years
Purchased and core technology \| Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Range of Useful Lives	8 years
Customer intangibles
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amounts	$ 24,700	24,700
Accumulated Amortization and Write-Offs	(24,700)	(20,601)
Net Carrying Amounts	$ 0	$ 4,099
Customer intangibles \| Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Range of Useful Lives	5 years
Customer intangibles \| Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Range of Useful Lives	7 years

Goodwill and Acquired Intangible Assets, Net - Future Amortization Expense of Identified Intangibles (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Fiscal Year
2018	$ 3,571
2019 and thereafter	0
Net Carrying Amounts	$ 3,571	$ 11,947

Restructuring and Other Related Charges - Summary of Restructuring and Other Related Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges	$ 105,186	$ 63,543	$ 13,824
Cost of goods sold
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges	0	10,292	0
Restructuring and other related charges
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges	105,186	53,251	10,438
Write-off of acquired intangible assets
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges	$ 0	$ 0	$ 3,386

Restructuring and Other Related Charges - Charges Related to Restructuring Actions (Details) - USD ($) $ in Thousands	5 Months Ended	12 Months Ended
	Aug. 01, 2015	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Restructuring and Related Activities [Abstract]
Severance and related costs		$ 41,035	$ 43,926	$ 5,181
Facilities and related costs		6,587	1,407	1,924
Loss on early contract termination		0	1,644	3,230
Other exit-related costs		5,452	534	86
Restructuring charges		53,074	47,511	10,421
Restructuring Cost and Reserve [Line Items]
Release of reserves		469
Impairment and write-off of assets:
Prepaid deposit		45,000	0	0
Inventory		0	8,046	0
Technology licenses		629	1,250	0
Equipment and other	$ 1,400	6,952	6,736	17
Acquired intangible asset		0	0	3,386
Restructuring and other related charges		105,186	63,543	13,824
Severance
Restructuring Cost and Reserve [Line Items]
Release of reserves		(86)	0	0
Other exit-related costs
Restructuring Cost and Reserve [Line Items]
Release of reserves		$ (383)	$ 0	$ 0

Restructuring and Other Related Charges - Additional Information (Details)	1 Months Ended		5 Months Ended	12 Months Ended
	Nov. 30, 2016 USD ($) position	Oct. 31, 2015 USD ($)	Aug. 01, 2015 USD ($)	Jan. 28, 2017 USD ($) employee	Jan. 30, 2016 USD ($) employee	Jan. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring and other related charges				$ 105,186,000	$ 63,543,000	$ 13,824,000
Total number of employees to be terminated \| position	900
Restructuring charges				53,074,000	47,511,000	10,421,000
Release of reserves				$ (469,000)
Number of employees departed and were paid severance and related benefit costs \| employee				500
Asset impairment charges			$ 1,400,000	$ 6,952,000	6,736,000	17,000
Proceeds from equipment held for sale		$ 9,300,000		0	10,007,000	0
Gain or loss recognized upon sale of equipment held for sale		$ 0
Loss on early contract termination				0	1,644,000	3,230,000
Severance
Restructuring Cost and Reserve [Line Items]
Release of reserves				86,000	0	0
Other exit-related costs
Restructuring Cost and Reserve [Line Items]
Release of reserves				383,000	0	$ 0
November 2016 Restructuring
Restructuring Cost and Reserve [Line Items]
Total number of employees to be terminated \| position	900
Restructuring charges				98,700,000
November 2016 Restructuring \| Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring costs, expected cost to incur	$ 90,000,000
Restructuring costs, expected cash charges	35,000,000
Restructuring, expected additional charges				10,000,000
November 2016 Restructuring \| Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring costs, expected cost to incur	110,000,000
Restructuring costs, expected cash charges	$ 50,000,000
Restructuring, expected additional charges				15,000,000
November 2016 Restructuring \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges				41,020,000	0
Release of reserves				0
November 2016 Restructuring \| Other exit-related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges				5,452,000	0
Release of reserves				0
November 2016 Restructuring \| Facilities and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges				1,872,000	0
Release of reserves				0
November 2016 Restructuring \| Contract termination
Restructuring Cost and Reserve [Line Items]
Restructuring charges				45,000,000
November 2016 Restructuring \| Impairment of equipment and technology licenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges				5,400,000
Mobile Platform Business
Restructuring Cost and Reserve [Line Items]
Restructuring charges				1,900,000	$ 44,400,000
Cumulative costs incurred				$ 46,400,000
Number of employees retained \| employee				140
Number of employees offered with retention bonuses \| employee				128
Mobile Platform Business \| Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring costs, expected cost to incur							$ 100,000,000
Mobile Platform Business \| Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring costs, expected cost to incur							$ 130,000,000
Mobile Platform Business \| Severance
Restructuring Cost and Reserve [Line Items]
Cumulative costs incurred				$ 28,100,000
Number of employees departed and were paid severance and related benefit costs \| employee					825
Mobile Platform Business \| Facilities and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges				4,600,000	$ 1,400,000
Cumulative costs incurred				200,000
Mobile Platform Business \| Contract termination
Restructuring Cost and Reserve [Line Items]
Release of reserves				300,000
Cumulative costs incurred				1,300,000
Mobile Platform Business \| Impairment of equipment and technology licenses
Restructuring Cost and Reserve [Line Items]
Cumulative costs incurred				8,800,000
Mobile Platform Business \| Write-off of assets held-for-sale
Restructuring Cost and Reserve [Line Items]
Restructuring charges				2,200,000
Mobile Platform Business \| Write down of inventory
Restructuring Cost and Reserve [Line Items]
Cumulative costs incurred				$ 8,000,000
Reduction in Operations in Israel and Closing of Other Design Centers
Restructuring Cost and Reserve [Line Items]
Total number of employees to be terminated \| employee					358
Restructuring charges					$ 16,300,000
Reduction in Operations in Israel and Closing of Other Design Centers \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges					15,100,000
Reduction in Operations in Israel and Closing of Other Design Centers \| Facilities and related costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 1,200,000

Restructuring and Other Related Charges - Reconciliation of Beginning and Ending Restructuring Liability Balances by Major Type of Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Restructuring Reserve [Roll Forward]
Balance at beginning of period	$ 3,842	$ 4,569
Cost reduction charges	53,074	47,511	$ 10,421
Cash payments	(32,459)	(48,072)
Release of reserves	(469)
Exchange rate adjustment	111	(136)
Balance at end of period	24,099	3,842	4,569
Less: non-current portion	(949)
Current portion	23,150	3,842
Severance and related costs
Restructuring Reserve [Roll Forward]
Release of reserves	86	0	0
Other exit-related costs
Restructuring Reserve [Roll Forward]
Release of reserves	383	0	0
November 2016 Restructuring
Restructuring Reserve [Roll Forward]
Cost reduction charges	98,700
November 2016 Restructuring \| Severance and related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0	0
Cost reduction charges	41,020	0
Cash payments	(24,065)	0
Release of reserves	0
Exchange rate adjustment	45	0
Balance at end of period	17,000	0	0
Less: non-current portion	0
Current portion	17,000
November 2016 Restructuring \| Facilities and related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0	0
Cost reduction charges	1,872	0
Cash payments	(110)	0
Release of reserves	0
Exchange rate adjustment	1	0
Balance at end of period	1,763	0	0
Less: non-current portion	(949)
Current portion	814
November 2016 Restructuring \| Other exit-related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	0	0
Cost reduction charges	5,452	0
Cash payments	(829)	0
Release of reserves	0
Exchange rate adjustment	2	0
Balance at end of period	4,625	0	0
Less: non-current portion	0
Current portion	4,625
Mobile & Other Prior Restructuring \| Severance and related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	1,155	0
Cost reduction charges	15	43,926
Cash payments	(1,082)	(42,741)
Release of reserves	(86)
Exchange rate adjustment	(2)	(30)
Balance at end of period	0	1,155	0
Less: non-current portion	0
Current portion	0
Mobile & Other Prior Restructuring \| Facilities and related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	1,043	1,339
Cost reduction charges	4,715	1,407
Cash payments	(5,112)	(1,567)
Release of reserves	0
Exchange rate adjustment	65	(106)
Balance at end of period	711	1,043	1,339
Less: non-current portion	0
Current portion	711
Mobile & Other Prior Restructuring \| Other exit-related costs
Restructuring Reserve [Roll Forward]
Balance at beginning of period	1,644	3,230
Cost reduction charges	0	2,178
Cash payments	(1,261)	(3,764)
Release of reserves	(383)
Exchange rate adjustment	0	0
Balance at end of period	0	$ 1,644	$ 3,230
Less: non-current portion	0
Current portion	$ 0

Income Taxes - U.S. and Non-U.S. Components of Income Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Income Tax Disclosure [Abstract]
U.S. operations	$ 30,889	$ 32,433	$ 30,607
Non-U.S. operations	86,127	(790,253)	449,103
Income before income taxes	$ 117,016	$ (757,820)	$ 479,710

Income Taxes - Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Current income tax provision (benefit):
Federal	$ 8,289	$ 10,482	$ 8,826
State	180	83	(161)
Foreign	19,916	(5,326)	171
Total current income tax provision (benefit)	28,385	5,239	8,836
Deferred income tax provision (benefit):
Federal	(5,062)	(4,355)	(1,775)
State	(12)	580	16
Foreign	49,711	9,871	(11,154)
Total deferred income tax provision (benefit)	44,637	6,096	(12,913)
Total provision (benefit) for income taxes	$ 73,022	$ 11,335	$ (4,077)

Income Taxes - Deferred Tax Assets (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Deferred tax assets:
Federal and California research and other tax credits	$ 450,503	$ 414,662
Reserves and accruals	35,887	35,200
Share-based compensation	3,733	4,476
Net operating losses	5,361	11,055
Gross deferred tax assets	495,484	465,393
Valuation allowance	(456,541)	(424,914)
Total deferred tax assets	38,943	40,479
Total deferred tax liabilities	(51,112)	(7,073)
Net deferred tax liabilities	$ (12,169)
Net deferred tax assets		$ 33,406

Income Taxes - Additional Information (Details)	1 Months Ended		3 Months Ended	12 Months Ended
Income Taxes - Additional Information (Details)	Jun. 30, 2014	Jul. 31, 1999	Jan. 28, 2017 USD ($) branch	Jan. 28, 2017 USD ($) branch $ / shares	Jan. 30, 2016 USD ($) $ / shares	Jan. 31, 2015 USD ($) $ / shares	Jan. 27, 2007
Income Taxes [Line Items]
Deferred tax assets for net operating losses available to be used			$ 7,500,000	$ 7,500,000	$ 6,300,000
Valuation allowance			456,541,000	456,541,000	$ 424,914,000
Increase in valuation allowance				$ 31,600,000
Federal statutory tax rate				35.00%	35.00%	35.00%
Unrecognized tax benefit that would affect the effective income tax rate if recognized			23,400,000	$ 23,400,000
Unrecognized tax benefits offset by deferred tax assets				7,500,000	$ 6,300,000
Unrecognized tax benefit, interest and penalties accrued			21,600,000	21,600,000	26,400,000	$ 27,700,000
Interest and penalties related to unrecognized tax benefits included in consolidated statements of operation				2,700,000	$ 4,600,000	$ 3,800,000
Uncertain tax positions decrease from the lapse of the statutes of limitation in various jurisdictions during the next 12 months			9,500,000	9,500,000
Tax expense on restructuring			66,900,000
Foreign withholding taxes on undistributed earnings of subsidiaries not permanently reinvested			50,100,000
Cash, cash equivalents and short-term investments			1,700,000,000	1,700,000,000
Undistributed earnings of foreign subsidiaries			$ 620,000,000	$ 620,000,000
Marvell Israel
Income Taxes [Line Items]
Number of branches entitled to tax programs \| branch			2	2
Foreign Subsidiaries
Income Taxes [Line Items]
Cash, cash equivalents and short-term investments			$ 970,000,000	$ 970,000,000
Increase (decrease) in tax expense in the event of undistributed earnings needed by parent company or no longer considered indefinitely reinvested outside of Bermuda				$ 190,000,000
Office of the Tax Commissioner, Bermuda
Income Taxes [Line Items]
Applicable statutory rate			0.00%	0.00%	0.00%	0.00%
Economic Development Board of Singapore Pioneer Status
Income Taxes [Line Items]
Expiration of tax exemption, period	15 years	10 years
Tax holidays, tax savings amount				$ 900,000	$ 5,300,000	$ 100,000
Tax holidays, per share effect on earnings (less than) (in usd per share) \| $ / shares				$ 0.01	$ 0.01	$ 0.01
Swiss Federal Department of Economy and the Vaud Cantonal Tax Administration Tax Holiday
Income Taxes [Line Items]
Expiration of tax exemption, period							10 years
Tax holidays, tax savings amount				$ 0	$ 3,700,000	$ 4,500,000
Tax holidays, per share effect on earnings (less than) (in usd per share) \| $ / shares					$ 0.01	$ 0.01
Foreign
Income Taxes [Line Items]
Net operating loss carryforwards			$ 82,700,000	82,700,000
Tax expense associated with restructuring actions			16,800,000
Federal
Income Taxes [Line Items]
Net operating loss carryforwards			1,400,000	1,400,000
Federal \| Research Tax Credit
Income Taxes [Line Items]
Tax credit carryforwards			268,500,000	268,500,000
Net operating loss carryforwards, amount attributable to excess tax benefits from stock options			63,000,000	63,000,000
State \| California
Income Taxes [Line Items]
Net operating loss carryforwards			6,300,000	6,300,000
State \| California \| Research Tax Credit
Income Taxes [Line Items]
Tax credit carryforwards			279,400,000	279,400,000
Net operating loss carryforwards, amount attributable to excess tax benefits from stock options			60,000,000	60,000,000
State \| Other State \| Research and Investment Tax Credit
Income Taxes [Line Items]
Tax credit carryforwards			$ 24,300,000	$ 24,300,000

Income Taxes - Reconciliation Between the Provision (Benefit) for Income Taxes at the Statutory Rate and the Effective Tax Rate (Details)	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Income Tax Disclosure [Abstract]
Provision at U.S. notional statutory rate	35.00%	35.00%	35.00%
Difference in U.S. and non-U.S. tax rates	(23.70%)	(37.10%)	(35.10%)
Benefits from utilization of general business credits	(35.80%)	5.20%	(10.80%)
Change in valuation allowance	30.60%	(4.30%)	9.50%
Withholding taxes	42.80%	0.00%	0.00%
Tax effects of global restructuring	14.30%	0.00%	0.00%
Other	(0.80%)	(0.30%)	0.50%
Effective tax rate	62.40%	(1.50%)	(0.90%)

Income Taxes - Changes in Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits as of the beginning of the period	$ 29,139	$ 45,197	$ 51,682
Increases related to prior year tax positions	2,080	304	976
Decreases related to prior year tax positions	0	(4,334)	(386)
Increases related to current year tax positions	2,363	4,237	5,356
Settlements	0	(704)	0
Lapse in the statute of limitations	(6,576)	(9,739)	(10,691)
Foreign exchange gain	(3,213)	(5,822)	(1,740)
Gross amounts of unrecognized tax benefits as of the end of the period	$ 23,793	$ 29,139	$ 45,197

Commitments and Contingencies - Warranty Obligations (Details)	12 Months Ended
	Jan. 28, 2017
Commitments and Contingencies Disclosure [Abstract]
Standard warranty period	90 days
Extended warranty period (more than)	1 year

Commitments and Contingencies - Lease Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Rent expense, net of sublease income	$ 23.7	$ 23.8	$ 26.1

Commitments and Contingencies - Future Minimum Lease Payments, Net of Estimated Sublease Income under Operating and Capital Leases (Details) $ in Thousands	Jan. 28, 2017 USD ($)
Minimum Operating Leases Payments
2018	$ 37,167
2019	27,004
2020	16,708
2021	3,767
2022	610
Thereafter	2,147
Total future minimum lease payments	$ 87,403

Commitments and Contingencies - Future Minimum Payments Under Technology License Obligations (Details) - USD ($) $ in Thousands	Jan. 28, 2017	Jan. 30, 2016
Fiscal Year
Less: current portion	$ (21,905)	$ (17,985)
Non-current portion	14,949	$ 12,461
Technology License Obligations
Fiscal Year
2018	23,180
2019	7,025
2020 and thereafter	7,025
Total future minimum lease payments	37,230
Less: amount representing interest	(170)
Present value of future minimum payments	37,060
Less: current portion	(22,111)
Non-current portion	$ 14,949

Commitments and Contingencies - Purchase Commitments (Details) $ in Millions	Jan. 28, 2017 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Purchase commitment, outstanding commitment	$ 208.8

Commitments and Contingencies - Contingencies (Details) $ in Millions						12 Months Ended
	Oct. 12, 2016	Feb. 16, 2016 USD ($)	Oct. 16, 2015 officer	Sep. 11, 2015 claims	Dec. 26, 2012 USD ($)	Jan. 28, 2017 USD ($)
Luna Litigation and Consolidated Cases
Loss Contingencies [Line Items]
Number of additional claims consolidated \| claims				2
Plaintiff's period to file an amended complaint	30 days
Saratoga Litigation
Loss Contingencies [Line Items]
Number of current officers and/or directors named in the action \| officer			8
CMU Litigation
Loss Contingencies [Line Items]
Loss contingency, awarded amount					$ 1,170.0	$ 1,540.0
Amount agreed to pay pursuant to settlement						$ 6.2
Settlement Agreement and Patent License
Loss Contingencies [Line Items]
Amount agreed to pay pursuant to settlement		$ 750.0
Primary Surety Bond
Loss Contingencies [Line Items]
Bond		439.0
Secondary Surety Bond
Loss Contingencies [Line Items]
Bond		$ 311.0

Commitments and Contingencies - Surety Bonds (Details) - USD ($) $ in Millions	Jan. 28, 2017	Feb. 16, 2016	Nov. 14, 2014	May 14, 2014
Santa Clara, California Campus
Loss Contingencies [Line Items]
Carrying value of pledged assets	$ 126.7
Surety Bond
Loss Contingencies [Line Items]
Bond			$ 216.0	$ 1,540.0
Commitment Letter
Loss Contingencies [Line Items]
Bond			$ 95.0
Primary Surety Bond
Loss Contingencies [Line Items]
Bond		$ 439.0
Secondary Surety Bond
Loss Contingencies [Line Items]
Bond		$ 311.0

Benefit Plans (Details) - USD ($)	12 Months Ended
Benefit Plans (Details) - USD ($)	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Foreign Defined Benefit Plan
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan, cost recognized	$ 100,000	$ 1,500,000	$ 100,000
U.S. Defined Contribution Plan
Defined Contribution Plan Disclosure [Line Items]
Maximum contribution per employee	3,000
Matching contributions to employees	$ 4,500,000	4,900,000	5,100,000
U.S. Defined Contribution Plan \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Employee pre-tax contributions to 401(k)	1.00%
U.S. Defined Contribution Plan \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Employee pre-tax contributions to 401(k)	50.00%
U.S. Defined Contribution Plan \| Defined Contribution Plan, Tranche One
Defined Contribution Plan Disclosure [Line Items]
Employee pre-tax contributions to 401(k)	4.00%
Employer match contributions percentage	100.00%
U.S. Defined Contribution Plan \| Defined Contribution Plan, Tranche Two
Defined Contribution Plan Disclosure [Line Items]
Employee pre-tax contributions to 401(k)	2.00%
Employer match contributions percentage	50.00%
Non-U.S. Defined Contribution Plan
Defined Contribution Plan Disclosure [Line Items]
Matching contributions to employees	$ 11,800,000	$ 14,500,000	$ 18,500,000

Shareholders’ Equity - Common and Preferred Stock (Details) - $ / shares	Jan. 28, 2017	Jan. 30, 2016
Equity [Abstract]
Common stock, shares authorized	992,000,000	992,000,000
Common stock, par value (in usd per share)	$ 0.002	$ 0.002
Preferred stock, shares authorized	8,000,000	8,000,000
Preferred stock, par value (in usd per share)	$ 0.002	$ 0.002
Preferred stock, shares outstanding	0	0

Shareholders’ Equity - 1995 Stock Option Plan (Details) shares in Millions	1 Months Ended	4 Months Ended	12 Months Ended
	Jun. 30, 2014	Dec. 31, 2016 employee	Jan. 28, 2017 shares	Jan. 31, 2015
Performance-based Equity Awards \| Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees who later joined the Company who were granted with equity awards \| employee		4
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected achievement percentage of performance awards			100.00%
Employee Stock Option Plan, 1995 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance, authorized			383.4
Equity awards, expiration period			10 years
Number of shares available for future issuance			98.6
Employee Stock Option Plan, 1995 Plan \| Incentive Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, expiration period			5 years
Percentage of ownership in outstanding stock (greater than)			10.00%
Employee Stock Option Plan, 1995 Plan \| Incentive Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option, purchase price as percentage of fair market value			110.00%
Equity awards, vesting period			2 years
Employee Stock Option Plan, 1995 Plan \| Incentive Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting period			5 years
Employee Stock Option Plan, 1995 Plan \| Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting period	2 years
Employee Stock Option Plan, 1995 Plan \| Performance RSUs \| Vesting on April 1, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage	50.00%
Employee Stock Option Plan, 1995 Plan \| Performance RSUs \| Vesting on April 1, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage	50.00%
Employee Stock Option Plan, 1995 Plan \| Financial Performance RSU \| First Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage				50.00%
Employee Stock Option Plan, 1995 Plan \| Financial Performance RSU \| Second Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage				50.00%
Employee Stock Option Plan, 1995 Plan \| Strategic Performance Award \| First Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage				50.00%
Employee Stock Option Plan, 1995 Plan \| Strategic Performance Award \| Second Anniversary
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, vesting percentage				50.00%

Shareholders’ Equity - Outside Director Equity Compensation Policy (Details) - Outside Director Equity Compensation Policy - RSUs $ in Thousands	12 Months Ended
	Jan. 28, 2017 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, aggregate fair market value \| $	$ 220
Equity awards, vesting percentage	100.00%
Equity awards, vesting period	1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized \| shares	20,000

Shareholders’ Equity - 2000 Employee Stock Purchase Plan (Details) - the ESPP - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Feb. 02, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum subscription rate	15.00%
Look-back period	24 months
Offering period	24 months
Percentage discount of purchase price per share of common shares	85.00%
Purchase period				6 months
Number of shares issued	2.3	5.9	9.7
Weighted-average price (in usd per share)	$ 7.33	$ 10.00	$ 7.67
Unamortized compensation expense	$ 16.2
Number of shares available for future issuance	29.5

Shareholders’ Equity - Stock Option Plan Activity (Details) - $ / shares shares in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Jan. 28, 2012
Number of Shares
Balance at beginning of period (in shares)	43,030	49,372	51,779
Granted (in shares)	2,104	6,170	6,365
Exercised (in shares)	(5,558)	(2,225)	(3,732)
Canceled/Forfeited (in shares)	(14,480)	(10,287)	(5,040)
Balance at end of period (in shares)	25,096	43,030	49,372
Weighted Average Exercise Price
Balance at beginning of period (in usd per share)	$ 13.68	$ 13.88	$ 13.51
Granted (in usd per share)	9.99	14.13	15.33
Exercised (in usd per share)	10.35	9.79	10.19
Canceled/Forfeited (in usd per share)	16.29	15.68	14.72
Balance at end of period (in usd per share)	$ 12.61	$ 13.68	$ 13.88
Time-Based Options
Number of Shares
Balance at beginning of period (in shares)	40,874	47,140	49,156
Granted (in shares)	2,104	6,170	6,365
Exercised (in shares)	(5,558)	(2,225)	(3,732)
Canceled/Forfeited (in shares)	(12,324)	(10,211)	(4,649)
Balance at end of period (in shares)	25,096	40,874	47,140
Vested or expected to vest at end of period (in shares)	24,253
Weighted Average Exercise Price
Balance at beginning of period (in usd per share)	$ 13.59	$ 13.79	$ 13.40
Granted (in usd per share)	9.99	14.13	15.33
Exercised (in usd per share)	10.35	9.79	10.19
Canceled/Forfeited (in usd per share)	16.44	15.68	14.66
Balance at end of period (in usd per share)	12.61	$ 13.59	$ 13.79
Vested or expected to vest at end of period (in usd per share)	$ 12.57
Market-Based Options
Number of Shares
Balance at beginning of period (in shares)	2,156	2,232	2,623
Granted (in shares)	0	0	0	3,100
Exercised (in shares)	0	0	0
Canceled/Forfeited (in shares)	(2,156)	(76)	(391)
Balance at end of period (in shares)	0	2,156	2,232
Weighted Average Exercise Price
Balance at beginning of period (in usd per share)	$ 15.43	$ 15.43	$ 15.43
Granted (in usd per share)	0.00	0.00	0.00
Exercised (in usd per share)	0.00	0.00	0.00
Canceled/Forfeited (in usd per share)	$ 15.43	15.43	15.43
Balance at end of period (in usd per share)		$ 15.43	$ 15.43

Shareholders’ Equity - Option Plan and Stock Award Activity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	12 Months Ended
	Apr. 01, 2016	Apr. 01, 2015	Apr. 30, 2016	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Jan. 27, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Closing stock price (in usd per share)							$ 15.09
Time-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options vested and expected to vest, aggregate intrinsic value				$ 68.0
Options exercisable, aggregate intrinsic value				45.7
Aggregate intrinsic value of stock options exercised				19.8	$ 9.7	$ 19.3
Unamortized compensation expense				$ 15.5
Unrecognized share based compensation cost, weighted-average period of recognition (in years)				1 year 5 months 5 days
Market-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards, expiration period			5 years
Performance RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested		360,723		155,000	658,000	3,000
Number of shares granted				366,000	669,000	1,277,000
Performance RSUs \| Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested	33,616	478,001
Number of shares granted		107,954
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense				$ 64.2
Unrecognized share based compensation cost, weighted-average period of recognition (in years)				1 year 4 months 28 days
Number of shares vested				5,645,000	5,797,000	5,941,000
Number of shares granted				10,117,000	6,765,000	6,811,000
Restricted stock units, aggregate intrinsic value				$ 152.4
Restricted stock units vested and expected to vest (in shares)				10,100,000

Shareholders’ Equity - Schedule of Outstanding Options and Exercisable Options Information, by Range of Exercise Prices (Details) shares in Thousands	12 Months Ended
	Jan. 28, 2017 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Outstanding Options, Number of Shares \| shares	25,096
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	5 years 3 months 7 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 12.61
Exercisable Options, Number of Shares \| shares	14,172
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 12.23
Range One
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit (in usd per share)	5.70
Range of Exercise Prices, Upper Limit (in usd per share)	$ 10.47
Outstanding Options, Number of Shares \| shares	3,842
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	4 years 10 months 2 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 8.11
Exercisable Options, Number of Shares \| shares	2,214
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 6.94
Range Two
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit (in usd per share)	10.76
Range of Exercise Prices, Upper Limit (in usd per share)	$ 10.76
Outstanding Options, Number of Shares \| shares	7,004
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	6 years 1 month 27 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 10.76
Exercisable Options, Number of Shares \| shares	4,344
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 10.76
Range Three
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit (in usd per share)	10.80
Range of Exercise Prices, Upper Limit (in usd per share)	$ 14.35
Outstanding Options, Number of Shares \| shares	6,047
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	5 years 9 months 14 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 13.13
Exercisable Options, Number of Shares \| shares	2,630
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 11.72
Range Four
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit (in usd per share)	14.45
Range of Exercise Prices, Upper Limit (in usd per share)	$ 15.87
Outstanding Options, Number of Shares \| shares	5,540
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	5 years 9 months 25 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 15.40
Exercisable Options, Number of Shares \| shares	2,385
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 15.24
Range Five
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit (in usd per share)	15.91
Range of Exercise Prices, Upper Limit (in usd per share)	$ 21.62
Outstanding Options, Number of Shares \| shares	2,663
Outstanding Options, Weighted Average Remaining Contractual Term (in Years)	1 year 2 months 8 days
Outstanding Options, Weighted Average Exercise Price (in usd per share)	$ 16.95
Exercisable Options, Number of Shares \| shares	2,599
Exercisable Options, Weighted Average Exercise Price (in usd per share)	$ 16.96

Shareholders’ Equity - Activity Related to Non Vested Portion of Restricted Stock Units (Details) - $ / shares			12 Months Ended
	Apr. 01, 2016	Apr. 01, 2015	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Time-Based
Number of Shares
Beginning Balance (in shares)			8,343,000	9,748,000	11,254,000
Granted (in shares)			9,139,000	5,689,000	5,534,000
Vested (in shares)			(5,490,000)	(5,139,000)	(5,938,000)
Canceled/Forfeited (in shares)			(2,067,000)	(1,955,000)	(1,102,000)
Ending Balance (in shares)			9,925,000	8,343,000	9,748,000
Weighted Average Grant Date Fair Value
Beginning Balance (in usd per share)			$ 13.57	$ 14.84	$ 14.14
Granted (in usd per share)			9.83	12.88	15.20
Vested (in usd per share)			13.95	15.06	13.96
Canceled/Forfeited (in usd per share)			10.69	13.99	14.32
Ending Balance (in usd per share)			$ 10.52	$ 13.57	$ 14.84
Performance-Based
Number of Shares
Beginning Balance (in shares)			977,000	1,254,000	100,000
Granted (in shares)			366,000	669,000	1,277,000
Vested (in shares)		(360,723)	(155,000)	(658,000)	(3,000)
Canceled/Forfeited (in shares)			(875,000)	(288,000)	(120,000)
Ending Balance (in shares)			313,000	977,000	1,254,000
Weighted Average Grant Date Fair Value
Beginning Balance (in usd per share)			$ 14.43	$ 14.99	$ 10.52
Granted (in usd per share)			13.91	14.08	14.98
Vested (in usd per share)			14.15	15.15	10.52
Canceled/Forfeited (in usd per share)			14.45	14.39	11.23
Ending Balance (in usd per share)			$ 13.91	$ 14.43	$ 14.99
Performance-Based \| Executive Officers
Number of Shares
Granted (in shares)		107,954
Vested (in shares)	(33,616)	(478,001)
Market-Based
Number of Shares
Beginning Balance (in shares)			353,000
Granted (in shares)			612,000	407,000
Vested (in shares)			0	0
Canceled/Forfeited (in shares)			(406,000)	(54,000)
Ending Balance (in shares)			559,000	353,000
Weighted Average Grant Date Fair Value
Beginning Balance (in usd per share)			$ 12.24
Granted (in usd per share)			11.94	$ 12.24
Vested (in usd per share)			0.00	0.00
Canceled/Forfeited (in usd per share)			12.39	12.24
Ending Balance (in usd per share)			$ 11.80	$ 12.24
Total
Number of Shares
Beginning Balance (in shares)			9,673,000	11,002,000	11,354,000
Granted (in shares)			10,117,000	6,765,000	6,811,000
Vested (in shares)			(5,645,000)	(5,797,000)	(5,941,000)
Canceled/Forfeited (in shares)			(3,348,000)	(2,297,000)	(1,222,000)
Ending Balance (in shares)			10,797,000	9,673,000	11,002,000
Weighted Average Grant Date Fair Value
Beginning Balance (in usd per share)			$ 13.61	$ 14.85	$ 14.11
Granted (in usd per share)			10.11	12.96	15.16
Vested (in usd per share)			13.95	15.07	13.96
Canceled/Forfeited (in usd per share)			11.88	14.00	14.02
Ending Balance (in usd per share)			$ 10.69	$ 13.61	$ 14.85
Total \| Executive Officers \| Maximum
Weighted Average Grant Date Fair Value
Equity awards, vesting percentage			200.00%

Shareholders’ Equity - Total Stock Compensation by Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	$ 113,970	$ 133,779	$ 137,246
Continuing operations
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	104,760	125,961	131,018
Continuing operations \| Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	8,334	7,787	7,972
Continuing operations \| Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	78,136	92,054	89,131
Continuing operations \| Selling and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	10,243	10,242	10,623
Continuing operations \| General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	8,047	15,878	23,292
Discontinued operations
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	9,210	7,818	6,228
Discontinued operations \| Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	187	129	0
Discontinued operations \| Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	8,306	6,738	5,301
Discontinued operations \| Selling and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	649	864	846
Discontinued operations \| General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total share-based compensation	$ 68	$ 87	$ 81

Shareholders’ Equity - Share-based Compensation (Details) - USD ($) $ in Millions	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Equity [Abstract]
Share-based compensation capitalized in inventory	$ 0.9	$ 1.5	$ 1.5

Shareholders’ Equity - Weighted Average Assumptions Used to Calculate Fair Value of Time Based Stock Option Award (Details) - Time-Based Options - $ / shares	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value (in usd per share)	$ 2.92	$ 3.93	$ 4.35
Expected volatility (as a percent)	40.00%	34.00%	35.00%
Expected term (in years)	5 years 2 months 12 days	5 years 4 months 24 days	5 years
Risk-free interest rate (as a percent)	1.30%	1.60%	1.60%
Expected dividend yield (as a percent)	2.50%	1.80%	1.60%

Shareholders’ Equity - Valuation Assumptions (Narrative) (Details) - shares shares in Thousands	1 Months Ended	12 Months Ended
	Apr. 30, 2016	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Jan. 28, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued		2,104	6,170	6,365
Market-Based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares issued		0	0	0	3,100
Equity awards, expiration period	5 years

Shareholders’ Equity - Weighted Average Assumptions Used to Calculate Fair Value Awards for Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan - $ / shares	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated fair value (in usd per share)	$ 3.83	$ 3.24	$ 4.10
Expected volatility (as a percent)	39.00%	41.00%	30.00%
Expected term (in years)	1 year 2 months 12 days	1 year 3 months 18 days	1 year 3 months 18 days
Risk-free interest rate (as a percent)	0.70%	0.60%	0.30%
Expected dividend yield (as a percent)	1.90%	2.40%	1.60%

Shareholders’ Equity - Weighted Average Assumptions Used to Calculate Fair Value Awards of Total Shareholder Return Awards (Details) - Total Shareholder Return	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	2 years 10 months 24 days	2 years
Expected volatility (as a percent)	36.00%	27.00%
Average correlation coefficient of peer companies	0.5	0.4
Risk-free interest rate (as a percent)	0.90%	0.50%
Expected dividend yield (as a percent)	2.10%	1.70%

Shareholders’ Equity - Share Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions	2 Months Ended	12 Months Ended			78 Months Ended
	Mar. 15, 2017	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Jan. 28, 2017	Nov. 27, 2016	Nov. 17, 2016
Equity [Abstract]
Share repurchase program, amount authorized			$ 3,250,000,000				$ 1,000,000,000
Share repurchase program, remaining available for future share repurchases		$ 884,000,000			$ 884,000,000	$ 115,000,000
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased		13.3	19.7	5.1	254.9
Amount of shares repurchased		$ 183,064,000	$ 260,875,000	$ 64,962,000	$ 3,300,000,000
Subsequent Event
Equity, Class of Treasury Stock [Line Items]
Number of shares repurchased	2.7
Amount of shares repurchased	$ 43,700,000
Shares repurchased, average price per share (in usd per share)	$ 15.91

Shareholders’ Equity - Dividends (Details) - $ / shares		12 Months Ended
Shareholders’ Equity - Dividends (Details) - $ / shares	Mar. 16, 2017	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Subsequent Event [Line Items]
Cash dividends declared per share (in usd per share)		$ 0.24	$ 0.24	$ 0.24
Subsequent Event
Subsequent Event [Line Items]
Cash dividends declared per share (in usd per share)	$ 0.06

Segment and Geographic Information - Additional Information (Details)	12 Months Ended
	Jan. 28, 2017 segment
Segment Reporting [Abstract]
Number of reportable segments	1

Segment and Geographic Information - Net Revenue and Long-Lived Asset Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	$ 2,317,674	$ 2,649,216	$ 3,637,206
Property and equipment, net	243,397	296,778
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	51,416	60,119	61,470
Property and equipment, net	147,552	173,158
China
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	1,239,931	1,509,244	2,171,299
Property and equipment, net	16,484	22,294
Thailand
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	113,778	189,299	294,706
Malaysia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	286,267	302,953	377,903
Philippines
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	283,345	211,602	254,381
Others
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenue	342,937	375,999	$ 477,447
Property and equipment, net	13,174	18,045
Israel
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	12,133	15,069
Singapore
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, net	$ 54,054	$ 68,212

Related Party Transactions (Details) - USD ($)	12 Months Ended
Related Party Transactions (Details) - USD ($)	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Feb. 28, 2015
Veri Silicon Holdings Company Limited
Related Party Transaction [Line Items]
Liability to related party	$ 100,000
Veri Silicon Holdings Company Limited \| Technology License Obligations
Related Party Transaction [Line Items]
Amount of transactions with related parties	1,500,000	$ 1,800,000	$ 3,700,000
Vivante Corporation
Related Party Transaction [Line Items]
Liability to related party	0
Vivante Corporation \| Restated Technology Agreement
Related Party Transaction [Line Items]
Amount of transactions with related parties	3,500,000	$ 4,000,000	$ 9,100,000
Former Chairman and Chief Executive Officer and President and Director
Related Party Transaction [Line Items]
Amount of transactions with related parties	8,400,000
Liability to related party	$ 7,000,000			$ 15,400,000
Percentage of ownership in outstanding stock (greater than)	10.00%

Carnegie Mellon University Settlement (Details) - USD ($) $ in Millions		12 Months Ended
	Feb. 16, 2016	Jan. 28, 2017	Jan. 30, 2016
Settlement Agreement and Patent License
Loss Contingencies [Line Items]
Litigation settlement, amount	$ 750.0
CMU Litigation
Loss Contingencies [Line Items]
Litigation settlement, amount		$ 6.2
CMU Litigation \| Cost Of Goods Sold For Past Use
Loss Contingencies [Line Items]
Litigation settlement, amount			$ 81.3
CMU Litigation \| Mutual Release Of Claims And Covenant Not To Sue Provisions \| Operating Expenses
Loss Contingencies [Line Items]
Litigation settlement, amount			654.7
CMU Litigation \| Future License Settlement \| Cost Of Goods Sold For Past Use
Loss Contingencies [Line Items]
Litigation settlement, amount			$ 14.0

Changes in the Company's Organization (Details)	1 Months Ended
Changes in the Company's Organization (Details)	Apr. 30, 2016 director
Reorganizations [Abstract]
Number of independent directors serving on the Board	4

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015
Allowance for doubtful accounts and sales return reserve
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 2,762	$ 2,112	$ 2,294
Additions	4,456	2,614	3,041
Deductions	(5,834)	(1,964)	(3,223)
Balance at End of Year	1,384	2,762	2,112
Deferred tax valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	424,914	382,796	335,890
Additions	31,627	42,118	46,906
Deductions	0	0	0
Balance at End of Year	$ 456,541	$ 424,914	$ 382,796