PMC Sierra (PMCS) 10-Q 3 Nov 15 2015 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 26, 2015	Nov. 02, 2015
Document And Entity Information [Abstract]
Entity Registrant Name	PMC SIERRA INC
Entity Filer Category	Large Accelerated Filer
Entity Central Index Key	767,920
Trading Symbol	pmcs
Amendment Flag	false
Document Type	10-Q
Document Fiscal Period Focus	Q3
Document Period End Date	Sep. 26, 2015
Document Fiscal Year Focus	2,015
Current Fiscal Year End Date	--12-26
Entity Common Stock, Shares Outstanding		198,759,058

Condensed Consolidated Statemen

Condensed Consolidated Statements Of Operations - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Condensed Consolidated Statements Of Operations [Abstract]
Net revenues		$ 133,574	$ 135,462	$ 391,412	$ 388,752
Cost of revenues (excluding amortization of purchased intangible assets below)		37,999	40,306	116,413	114,694
Gross profit		95,575	95,156	274,999	274,058
Research and development, net		47,277	48,441	151,976	147,977
Selling, general and administrative		28,050	29,265	88,589	87,596
Amortization of purchased intangible assets		9,172	9,948	27,758	32,225
Income from operations		11,076	7,502	6,676	6,260
Other income (expense):
Foreign exchange gain		2,412	899	4,058	642
Interest and other financial income, net		108	198	589	321
Gain on investment securities and other investments		70	12	127	87
Amortization of debt issuance costs		(51)	(51)	(153)	(153)
Accretion of discount on short-term and long-term obligation		(170)		(560)
Income before income taxes		13,445	8,560	10,737	7,157
Provision for income taxes		(6,727)	(3,087)	(7,943)	(9,405)
Net income (loss)		$ 6,718	$ 5,473	$ 2,794	$ (2,248)
Net income (loss) per common share - basic and diluted		$ 0.03	$ 0.03	$ 0.01	$ (0.01)
Shares used in per share calculation - basic		194,562	197,613	196,848	196,305
Shares used in per share calculation - diluted	[1]	196,865	200,744	201,018	196,305
[1]	PMC-Sierra Ltd. special shares are included in the calculation of basic and diluted weighted average common shares outstanding.

Condensed Consolidated Stateme3

Condensed Consolidated Statements Of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Condensed Consolidated Statements Of Comprehensive Loss [Abstract]
Net income (loss)	$ 6,718	$ 5,473	$ 2,794	$ (2,248)
Other comprehensive income (loss):
Change in fair value of derivatives, net of tax of nil, $227, nil and $41	(2,707)	(745)	(687)	(217)
Change in fair value of investment securities, net of tax of nil, $47, nil and $13	(13)	(134)	229	(37)
Other comprehensive loss	(2,720)	(879)	(458)	(254)
Comprehensive income (loss)	$ 3,998	$ 4,594	$ 2,336	$ (2,502)

Condensed Consolidated Stateme4

Condensed Consolidated Statements Of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Condensed Consolidated Statements Of Comprehensive Loss [Abstract]
Change in fair value of derivatives, tax		$ 227		$ 41
Change in fair value of investment securities, tax		$ 47		$ 13

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Current assets:
Cash and cash equivalents	$ 73,130	$ 112,570
Short-term investments	42,347	45,885
Accounts receivable, net of allowance for doubtful accounts of $735 (2014 - $795)	62,269	55,414
Inventories, net	32,846	37,949
Prepaid expenses and other current assets	12,020	16,473
Income taxes receivable	1,147	1,968
Prepaid income taxes		51
Deferred income tax assets	5,211	5,442
Total current assets	228,970	275,752
Investment securities	134,400	107,509
Investments and other assets	6,328	7,683
Prepaid income taxes	93	42
Property and equipment, net	37,871	37,311
Goodwill	283,239	283,239
Intangible assets, net	116,945	143,680
Deferred income tax assets	13,218	13,412
Income taxes receivable	440	457
Total assets	821,504	869,085
Current liabilities:
Accounts payable	18,261	23,360
Accrued liabilities	55,172	74,135
Credit facility	30,000
Income taxes payable	626	1,062
Liability for unrecognized tax benefit	14,001	16,076
Deferred income tax liabilities	7,677	7,644
Deferred income	4,515	4,530
Total current liabilities	130,252	126,807
Long-term obligations	28,396	36,305
Deferred income tax liabilities	56,182	53,493
Liability for unrecognized tax benefit	27,107	25,244
PMC special shares convertible into 203 (2014 - 278) shares of common stock	475	745
Stockholders' equity:
Common stock, par value $0.001: 900,000 shares authorized; 195,642 shares issued and outstanding (2014 - 199,518)	196	200
Additional paid in capital	1,599,345	1,595,609
Accumulated other comprehensive loss	(2,813)	(2,355)
Accumulated deficit	(1,017,636)	(966,963)
Total stockholders' equity	579,092	626,491
Total liabilities and stockholders' equity	$ 821,504	$ 869,085

Condensed Consolidated Balance6

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Condensed Consolidated Balance Sheets [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 735	$ 795
PMC special shares convertible into common stock, shares	203,000	278,000
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	900,000,000	900,000,000
Common stock, shares issued	195,642,000	199,518,000
Common stock, shares outstanding	195,642,000	199,518,000

Condensed Consolidated Stateme7

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014
Cash flows from operating activities:
Net income (loss)	$ 2,794	$ (2,248)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	45,166	48,739
Stock-based compensation	17,994	16,334
Unrealized foreign exchange gain, net	(8,179)	(2,372)
Net amortization of premiums and accrued interest on investments	587	628
Asset impairments	252	770
Gain on disposal of property and equipment	(63)
Gain on investment securities and other investments	(64)	(86)
Accretion of discount on short-term and long-term obligations	560
Amortization of debt issuance costs	153	153
Gain on exit of lease agreement	(696)
Changes in operating assets and liabilities:
Accounts receivable, net	(6,855)	(934)
Inventories, net	5,103	(3,514)
Prepaid expenses and other current assets	2,306	4,072
Accounts payable and accrued liabilities	(9,732)	(6,699)
Deferred taxes and income taxes payable	7,480	8,608
Deferred income	(15)	(1,980)
Net cash provided by operating activities	56,791	61,471
Cash flows from investing activities:
Cash paid in connection with business acquisition		(10,000)
Purchases of property and equipment	(13,724)	(11,175)
Purchase of intangible assets	(4,072)	(1,167)
Redemption of short-term investments	28,131	4,920
Disposals of investment securities and other investments	40,446	37,936
Purchases of investment securities and other investments	(92,577)	(67,727)
Net cash used in investing activities	(41,796)	(47,213)
Cash flows from financing activities:
Installment payment in connection with previous business acquisition	(18,000)
Proceeds from credit facility	102,000	30,000
Repayment of credit facility	(72,000)	(60,000)
Proceeds from issuance of common stock	36,982	17,924
Repurchases of common stock	(102,108)	(11,496)
Net cash used in financing activities	(53,126)	(23,572)
Effect of exchange rate changes on cash and cash equivalents	(1,309)	(784)
Net decrease in cash and cash equivalents	(39,440)	(10,098)
Cash and cash equivalents, beginning of the period	112,570	100,038
Cash and cash equivalents, end of the period	73,130	89,940
Supplemental disclosures of cash flow information:
Cash paid for interest	(483)	(276)
Cash payments made for income taxes, net of refunds received	$ (827)	$ (747)

Summary Of Significant Accounti

Summary Of Significant Accounting Policies	9 Months Ended
	Sep. 26, 2015
Summary Of Significant Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	NOTE 1. Summary of Significant Accounting Policies Description of business . PMC-Sierra, Inc. (the “Company” or “PMC”) is a fabless semiconductor and software solution innovator transforming networks that connect, move, and store Big Data. The Company designs, develops, markets and supports semiconductor, embedded software, and board level solutions by integrating its mixed-signal, software and systems expertise through a network of offices in North America, Europe and Asia. Building on a track record of technology leadership, the Company is driving innovation across storage, optical and mobile networks. PMC ’ s highly integrated solutions increase performance and enable next generation services to accelerate the network transformation. Basis of presentation. The accompanying interim condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) and United States Generally Accepted Accounting Principles (“GAAP”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules or regulations. These interim condensed consolidated financial statements are unaudited, but reflect all adjustments which are normal and recurring in nature and are, in the opinion of management, necessary to provide a fair statement of results for the interim periods presented. These interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes in the Company ’ s Annual Report on Form 10-K for the year ended December 27, 2014 filed with the SEC on February 24, 2015. The results of operations for the interim periods are not necessarily indicative of results to be expected in future periods. Fiscal 2015 will consist of 52 weeks and will end on Saturday, December 26, 2015. Fiscal 2014 consisted of 52 weeks and ended on Saturday, December 27, 2014. The third quarter of each of 2015 and 2014 consisted of 13 weeks. The Company’s reporting currency is the United States (“U.S.”) dollar and presented in thousands unless otherwise stated. Estimates . The preparation of financial statements and related disclosures in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Estimates are used for, but not limited to, stock-based compensation, purchase accounting assumptions including those used to calculate the fair value of intangible assets and goodwill, the valuation of investments, accounting for doubtful accounts, inventory reserves, depreciation and amortization, asset impairments, revenue recognition, sales returns, warranty costs, restructuring costs, income taxes including uncertain tax positions, accounting for employee benefit plans, and contingencies. Actual results could differ materially from these estimates. Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-03, Simplifying the Presentation of Debt Issuance Costs, which requires that debt issuance costs related to recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU requires retrospective adoption and will be effective for us beginning in our first quarter of 2017. Early adoption is permitted. ASU 2015-13 is not expected to have a material impact on the Company’s condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers , or ASU 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The standard will replace most existing revenue recognition guidance in GAAP when it becomes effective. The standard allows for either full retrospective or modified retrospective adoption method. In July 2015, the FASB deferred the effective date to January 1, 2018 with early adoption beginning January 1, 2017. The Company is currently evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method, adoption date, or determined the effect of the standard on its ongoing financial reporting. In July 2015, the FASB issued ASU 2015-11, Inventory - Simplifying the Measurement of Inventory (Topic 330) . ASU 2015-11 requires inventory to be subsequently measured using the lower of cost and net realizable value, thereby eliminating the market value approach. Net realizable value is defined as the “estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation.” ASU 2015-11 is effective for reporting periods beginning after December 15, 2016 and is applied prospectively. Early adoption is permitted. We are currently evaluating the impact that this guidance will have on our financial statements and disclosure.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 26, 2015
Business Combinations [Abstract]
Business Combinations	NOTE 2. Business Combinations Acquisition of RAID Software License On September 4, 2014 (“Effective Date”), PMC completed a transaction agreement with Hewlett-Packard Company (“HP”) to license core HP Smart Array (“RAID”) software, firmware and management technology (the “Transaction”) for total acquisition consideration of $52 million, accounted for using the acquisition method. With this technology, as well as with certain key employees who worked for HP as lead RAID software development engineers and who were transferred to PMC, PMC can provide more system value to new and existing enterprise, Hyperscale data center and channel customers. The $52 million total acquisition consideration is payable in installments. An initial payment of $10 million was made on the Effective Date and $18 million was paid on January 10, 2015. The remaining $24 million is payable in two installments of $12 million each on January 10, 2016 and January 10, 2017. Such installment payments are classified as financing activities in our condensed consolidated statement of cash flows. Other Agreement with HP Upon the closing of the Transaction, the Company also entered into an agreement with HP related to services and non-recurring engineering (“NRE”) which provides the framework for the development of future generations of RAID software for HP for a period of approximately two years from the Effective Date. During this period, HP will make cost reimbursement payments to the Company totaling $25 million, which are receivable in installments through April 2016. The Company received $3.3 million of the $25 million total cost reimbursement payments from HP in the third quarter of 2015 ( $9.8 million in the first nine months of 2015 and $13.8 million since the Effective Date). Payments to the Company in accordance with this agreement are recorded as a reduction of research and development expense.

Derivative Instruments

Derivative Instruments	9 Months Ended
	Sep. 26, 2015
Derivative Instruments [Abstract]
Derivative Instruments	NOTE 3. Derivative Instruments The Company generates revenues in U.S. dollars but incurs a portion of its operating expenses in foreign currencies, primarily the Canadian dollar. To minimize the short-term impact of foreign currency fluctuations on the Company ’ s operating expenses, the Company purchases forward currency contracts. The Company’s accounting policies for these instruments are based on whether the instruments are classified as designated or non-designated hedging instruments. The Company records all derivatives in the Condensed Consolidated Balance Sheets at fair value. The changes in the fair values of the effective portions of designated cash flow hedges are recorded in Accumulated other comprehensive income (loss) until the hedged item is recognized in earnings. Derivatives that are not designated as hedging instruments and the ineffective portion of cash flow hedges are adjusted to fair value through earnings. The Company de-designates its cash flow hedges when the forecasted hedged transactions are realized or it is probable the forecasted hedged transactions will not occur in the initially identified time period. At such time, the associated gains and losses deferred in Accumulated other comprehensive income (loss) are reclassified immediately into earnings and any subsequent changes in the fair value of such derivative instruments are immediately recorded in earnings. The fair value of our derivative instruments are included in prepaid expenses and other assets or accrued liabilities. The Company did not recognize any net gains or losses related to the de-designation of discontinued cash flow hedges during the nine months ended September 26, 2015 . As at September 26, 2015 the Company had 79 forward currency contracts outstanding ( September 27, 2014 - 84 ), all with maturities of less than 15 months, which qualified and were designated as cash flow hedges. As of September 26, 2015 , the U.S. dollar notional amount of these contracts was $48.3 million ( September 27, 2014 - $35.5 million), and the contracts had an aggregate fair value loss of $2.7 million and $0.7 million for the three months ended September 26, 2015 and September 27, 2014 , respectively (aggregate fair value loss of 0.7 million and $0.2 million for the nine months ended September 26, 2015 and September 27, 2014 , respectively). These were recorded in Accumulated other comprehensive loss, net of taxes.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 26, 2015
Fair Value Measurements [Abstract]
Fair Value Measurements	NOTE 4. Fair Value Measurements ASC Topic 820 specifies a hierarchy of valuation techniques which requires an entity to maximize the use of observable inputs that may be used to measure fair value. The hierarchy is prioritized into three levels (with Level 3 being the lowest) defined as follows: Level 1: Inputs are based on quoted market prices for identical assets and liabilities in active markets at the measurement date. Level 2: Inputs include similar quoted prices for similar assets or liabilities; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3: Pricing inputs include significant inputs that are generally not observable in the marketplace. These inputs may be used with internally developed methodologies that result in management’s best estimate of fair value. The Company’s valuation techniques used to measure the fair value of money market funds and other financial instruments were derived from quoted prices in active markets for identical assets. The valuation techniques used to measure the fair value of all other financial instruments, all of which have counterparties with high credit ratings, were valued based on quoted market prices or model driven valuations using significant inputs derived from or corroborated by observable market data. In the third quarter of 2015, the Company reviewed and evaluated the observable market pricing data and volume of trading activity used in determining Level 1 and Level 2 assets and classified $9.5 million of investments as Level 2 that were reported as Level 1 at December 27, 2014. The Company also classified $10.1 million of investments as Level 1 that were reported as Level 2 at December 27, 2014. The Company’s derivative instruments are classified as Level 2 as of September 26, 2015 and December 27, 2014, as they are not actively traded and are valued using pricing models that use observable market inputs. There were no Level 3 assets or liabilities at September 26, 2015 or December 27, 2014. Assets/Liabilities Measured and Recorded at Fair Value on a Recurring Basis Financial assets measured on a recurring basis as at September 26, 2015 and December 27, 2014, are summarized below: Fair value, September 26, 2015 (in thousands) Level 1 Level 2 Assets: Money market funds $ $ — Corporate bonds and notes U.S. treasury and government agency notes — Foreign government and agency notes U.S. state and municipal securities Total assets $ $ Fair value, December 27, 2014 (in thousands) Level 1 Level 2 Assets: Money market funds $ $ — Corporate bonds and notes U.S. treasury and government agency notes Foreign government and agency notes U.S. state and municipal securities — Total assets $ $ These assets are included in Cash and cash equivalents, Short-term investments, and Long-term investment securities. See Note 7. Investment Securities . Financial liabilities measured on a recurring basis are summarized below: Fair value, September 26, 2015 (in thousands) Level 2 Current liabilities: Forward currency contracts $ Fair value, December 27, 2014 (in thousands) Level 2 Current liabilities: Forward currency contracts $ These are included in Accrued liabilities. There were no assets or liabilities measured and recorded at fair value on a non-recurring basis as of September 26, 2015 .

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 26, 2015
Stock-Based Compensation [Abstract]
Stock-Based Compensation	NOTE 5. Stock-Based Compensation The Company has two stock-based compensation plans. Neither of the Company ’ s stock-based awards under these plans are classified as liabilities. The Company recorded stock-based compensation expense for the three and nine months ended September 26, 2015 and September 27, 2014 as follows: Three Months Ended Nine Months Ended September 26, September 27, September 26, September 27, (in thousands) 2015 2014 2015 2014 Cost of revenues $ $ $ $ Research and development, net Selling, general and administrative Total $ $ $ $ The Company received cash of $37.0 million related to the issuance of common stock during the nine months ended September 26, 2015 ( September 27, 2014 - $17.9 million). Equity Award Plans The Company issues its equity awards under the provisions of its equity plans. Stock options are granted with an exercise price equal to the closing market price of the Company’s common stock at the grant date. The options generally expire within 10 years and vest over four years. Activity under the option plans during the nine months ended September 26, 2015 was as follows: Number of options Weighted average exercise price per share Weighted average remaining contractual term (years) Aggregate intrinsic value Outstanding, December 27, 2014 $ $ Granted $ Exercised $ Forfeited $ Expired $ Outstanding, September 26, 2015 $ $ Vested and expected to vest, September 26, 2015 $ $ Exercisable, September 26, 2015 $ $ The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the quoted price of the Company ’ s common stock for the options that were in-the-money at September 26, 2015 . Total forfeitures recorded amounted to $0.7 million and $1.8 million during the nine months ended September 26, 2015 , and September 27, 2014 , respectively. The fair value of the Company ’ s stock option awards granted to employees is estimated using a lattice-binomial valuation model. This model considers the contractual term of the option, the probability that the option will be exercised prior to the end of its contractual life, and the probability of termination or retirement of the option holder in computing the value of the option. The model requires the input of highly subjective assumptions including the expected stock price volatility and expected life. The Company ’ s estimates of expected volatilities are based on a weighted historical and market-based implied volatility. The Company uses historical data to estimate option exercises and employee terminations within the valuation model; separate groups of employees that have similar historical exercise behavior are considered separately for valuation purposes. The expected term of options granted is based on historical activity and represents the period of time that granted options are expected to be outstanding. The risk-free rate for periods within the expected life of the stock option is based on the U.S. Treasury yield curve in effect at the time of the grant. The fair values of the Company’s stock option awards were calculated for expense recognition using an estimated forfeiture rate, assuming no expected dividends and using the following weighted average assumptions: Nine Months Ended September 26, September 27, 2015 2014 Expected life (years) Expected volatility Risk-free interest rate The weighted average grant-date fair value per stock options granted during the nine months ended September 26, 2015 was $2. 11 (September 27, 2014 - $2.29 ) . The total intrinsic value of stock options exercised during the nine months ended September 26, 2015 was $9.6 million ( September 27, 2014 - $ 2.3 million). As of September 26, 2015 , there was $3.5 million of total unrecognized compensation costs related to unvested stock options granted under the plans, which is expected to be recognized over an average period of 2.9 years. Restricted Stock Units The Company has various stock award plans that allow for the issuance of Restricted Stock Units (“RSUs”) to employees and directors. On February 25, 2015, the Company made its annual grant of RSU awards to Executives based on the second performance-based program tied to Non-GAAP operating income targets for 2015-2017. The total fair value of these 2015 grants was estimated at $3.8 million and will be recognized as compensation expense over the award’s vesting terms, with 34% vesting on February 25, 2016, 33% on February 25, 2017 and 33% vesting on February 25, 2018. On August 25, 2015, the Company made its annual grant of RSU awards to Executives. The performance metric applicable to the RSUs granted under the first program remain based on the degree of achievement of Total Shareholder Return (“TSR”) relative to Global Industry Classification Standards (“GICS’) Semiconductor Companies (8-Digit) for the Performance Period (July 1, 2015 - June 30, 2017). The total estimated $1.5 million fair value of these 2015 awards will be recognized as compensation expense over the award’s vesting terms, with 50% vesting on August 25, 2017 and 50% vesting on August 25, 2018. A summary of RSU activity during the nine months ended September 26, 2015 is as follows: Restricted Stock Units Weighted Average Remaining Contractual Term (years) Aggregate intrinsic value Unvested units at December 27, 2014 $ Awarded - — Released - — Forfeited - — Unvested units at September 26, 2015 $ Restricted Stock Units expected to vest at September 26, 2015 $ The intrinsic value of RSUs vested during the nine months ended September 26, 2015 was $14.9 million. As of September 26, 2015 , total unrecognized compensation expense, adjusted for estimated forfeitures, related to unvested RSUs was $41.0 million, which is expected to be recognized over the next 2.8 years. Employee Stock Purchase Plan (“ESPP”) The Company’s 2011 Employee Stock Purchase Plan (the “2011 Plan”) was approved by stockholders at the 2010 Annual Meeting. The 2011 Plan became effective on February 11, 2011. Up to 12,000,000 shares of our Common Stock have been initially reserved for issuance under the 2011 Plan. At the Company’s 2015 annual stockholders meeting, the stockholders approved an increase of 7,000,000 shares of Common Stock to the 2011 Plan. During the nine months ended September 26, 2015 , 1,727,159 shares were issued under the 2011 Plan at a weighted average price of $5.91 per share. As of September 26, 2015 , 2,653,049 shares were available for future issuance under the 2011 Plan compared to 4,380,208 as at December 27, 2014 . The valuation inputs utilized to determine the grant date fair value per ESPP award granted were as follows: Nine Months Ended September 26, September 27, 2015 2014 Expected life (years) Expected volatility Risk-free interest rate The weighted average grant date fair value per ESPP award granted during the first nine months of 2015 was $1.93 . The total intrinsic value of ESPP shares issued during the first nine months of 2015 was $3.7 million. As of September 26, 2015 , total unrecognized compensation costs, adjusted for estimated forfeitures, related to non-vested ESPP awards was $1.1 million which is expected to be recognized over the next four months.

Balance Sheet Items

Balance Sheet Items	9 Months Ended
	Sep. 26, 2015
Balance Sheet Items [Abstract]
Balance Sheet Items	NOTE 6. Balance Sheet Items a. Inventories. Inventories (net of reserves of $7.2 million and $7.8 million at September 26, 2015 and December 27, 2014, respectively) were as follows: September 26, December 27, (in thousands) 2015 2014 Work-in-progress $ $ Finished goods $ $ b. Product warranties. The Company provides a limited warranty on most of its standard products and accrues for the estimated cost at the time of shipment. The Company estimates its warranty costs based on historical failure rates and related repair or replacement costs and periodically reassess these estimates as actual warranty activities occur. The changes in the Company ’ s accrued warranty obligations from December 27, 2014 to September 26, 2015 , and from December 28, 2013 to September 27, 2014 were as follows: Nine Months Ended September 26, September 27, (in thousands) 2015 2014 Balance, beginning of the period $ $ Accrual for new warranties issued Reduction for payments and product replacements Adjustments related to revisions and changes in estimate of warranty accrual Balance, end of the period $ $ During the three months ended September 26, 2015, the Company revised its estimate of the warranty provision necessary for certain product failure obligations resulting in a reduction in warranty accrual of approximately $0.7 million as the risk of product failures associated with this provision was determined to be no longer probable. The Company ’ s accrual for warranty obligations is included in Accrued liabilities in the interim Condensed Consolidated Balance Sheet. c. 2015 Restructuring costs During the second quarter of 2015, the Company began implementing a restructuring plan to reduce spending across the organization. This has involved a reduction in force of approximately 200 employees worldwide and other targeted spending reductions. In connection with this plan, the Company expects to incur charges of approximately $15 million to $16 million, including approximately $13 million to $14 million in charges related to employee severance and related compensation benefits and approximately $2 million in charges related to site closures, asset impairments, and completion costs. The Company expects to complete activities under its cost reduction plan by end of the fourth quarter 2016. Restructuring costs at the end of each period were as follows: Three Months Ended Nine Months Ended September 26, September 26, (in thousands) 2015 2015 Employee severance and related compensation benefits (recoveries) expense: Cost of revenues $ $ Research and development, net Selling, general and administrative Site closures and asset impairments Total restructuring costs $ $ The following summarizes the restructuring activity for the 2015 restructuring plan: (in thousands) Employee severance & related benefits compensation Site closures & assets impairment Total Accrued restructuring balance as of December 27, 2014 $ — $ — $ — Additional accruals Cash payments Adjustments and non-cash charges Accrued restructuring balance as of September 26, 2015 $ $ $ The accrued restructuring costs are expected to be settled and paid by end of the second quarter 201 6 and were recorded in Accrued liabilities in the Company’s Condensed and Consolidated Balance Sheet.

Investment Securities

Investment Securities	9 Months Ended
	Sep. 26, 2015
Investment Securities [Abstract]
Investment Securities	NOTE 7. Investment Securities The Company ’ s available for sale investments, by investment type, consists of the following at September 26, 2015 and December 27, 2014: September 26, 2015 (in thousands) Amortized Cost Gross Unrealized Gains* Gross Unrealized Losses Fair Value Cash equivalents: Money market funds $ $ — $ — $ Total cash equivalents — — Short-term investments: Corporate bonds and notes US treasury and government agency notes — Foreign government and agency notes US states and municipal securities — Total short-term investments Long-term investment securities: Corporate bonds and notes US treasury and government agency notes Foreign government and agency notes Total long-term investment securities Total $ $ $ $ * Gross unrealized gains include accrued interest on investments of $0.6 million which are included in the Consolidated Statement of Operations. The remainder of the gross unrealized gains and losses are included in the Consolidated Balance Sheet as Accumulated other comprehensive income (loss). December 27, 2014 (in thousands) Amortized Cost Gross Unrealized Gains* Gross Unrealized Losses Fair Value Cash equivalents: Money market funds $ $ — $ — $ Total cash equivalents — — Short-term investments: Corporate bonds and notes US treasury and government agency notes — Foreign government and agency notes — Total short-term investments Long-term investment securities: Corporate bonds and notes US treasury and government agency notes Foreign government and agency notes US states and municipal securities — Total long-term investment securities Total $ $ $ $ *Gross unrealized gains include accrued interest on investments of $0.6 million which are included in the Consolidated Statement of Operations. The remainder of the gross unrealized gains and losses are included in the Consolidated Balance Sheet as Accumulated other comprehensive income (loss). As of September 26, 2015 and December 27, 2014 , the fair value of certain of the Company ’ s available-for-sale securities was less than their cost basis. Management reviews various factors in determining whether to recognize an impairment charge related to these unrealized losses, including the current financial and credit market environment, the financial condition, near-term prospects of the issuer of the investment security, the magnitude of the unrealized loss compared to the cost of the investment, length of time the investment has been in a loss position and the Company ’ s intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery of market value. As of September 26, 2015 , the Company determined that all the unrealized losses are temporary in nature and recorded them as a component of Accumulated other comprehensive income (loss). Contractual maturities as of September 26, 2015 of the Company’s investment securities do not exceed three years. The majority of the contractual maturities are two to three years, and the balance has maturities of one year or less.

Credit Facility

Credit Facility	9 Months Ended
	Sep. 26, 2015
Credit Facility [Abstract]
Credit Facility	NOTE 8. Credit Facility As of September 26, 2015 , the Company had an available revolving line of credit with a group of banks under which the Company may borrow up to $100 million, of which $30 million was drawn (December 27, 2014 - nil ). The Company may request, from time to time, and subject to customary conditions, including receipt of commitments, that the revolving credit facility be increased by an aggregate amount not to exceed $150 million. Interest payments are based on LIBOR plus margins, where margins range from 1.75% to 2.25% per annum based on the Company’s leverage ratio. The revolving credit facility is available for general corporate purposes. The credit facility is collateralized by substantially all of the Company’s personal property. The Company’s obligations under the credit facility are jointly and severally guaranteed by material wholly-owned domestic subsidiaries of the Company. On October 14, 2015, subsequent to the third quarter of 2015 balance sheet date, the Company repaid $5 million of the outstanding balance as of September 26, 2015 .

Income Taxes

Income Taxes	9 Months Ended
	Sep. 26, 2015
Income Taxes [Abstract]
Income Taxes	NOTE 9. Income Taxes The Company recorded a provision for income taxes of $6.7 million and $7.9 million for the three and nine months ended September 26, 2015 , respectively. The Company recorded a provision for income taxes of $3.1 million and $9.4 million for the three and nine months ended September 27, 2014 , respectively. The Company’s effective tax rate was 50% and 36% for the three months ended September 26, 2015 and September 27, 2014 , respectively. For the third quarter of 2015, the difference between the Company’s effective tax rate and the 35% federal statutory rate results primarily from changes in accruals related to unrecognized tax benefits and non-deductible amortization of intangible assets, partially offset by foreign earnings eligible for tax rates lower than the federal statutory rate. For the third quarter of 2014, the difference between the Company’s effective tax rate and the 35% federal statutory rate results primarily from changes in accruals related to unrecognized tax benefits, non-deductible amortization of intangible assets, and amortization of prepaid taxes, partially offset by foreign earnings eligible for tax rates lower than the federal statutory rate and book losses that are not benefited for tax purposes. The Company’s effective tax rate was 74% and 131% for the nine months ended September 26, 2015 and September 27, 2014 , respectively. For the first nine months of 2015, the difference between the Company’s tax rate and the 35% federal statutory rate results primarily from changes in accruals related to unrecognized tax benefits and non-deductible amortization of intangible assets, partially offset by foreign earnings eligible for tax rates lower than the federal statutory rate. For the first nine months of 2014, the difference between the Company’s tax rate and the 35% federal statutory rate results primarily from changes in accruals related to unrecognized tax benefits, non-deductible amortization of intangible assets, and amortization of prepaid taxes, partially offset by foreign earnings eligible for tax rates lower than the federal statutory rate and book losses that are not benefited for tax purposes. As of September 26, 2015 and December 27, 2014 , the Company’s liability for unrecognized tax benefits on a world-wide consolidated basis was $41.1 million and $41.3 million, respectively. The ultimate recognition of an amount different from this estimate would affect the Company’s effective tax rate.

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 26, 2015
Net Loss Per Share [Abstract]
Net Loss Per Share	NOTE 10. Net Income (Loss) Per Share The following table sets forth the computation of basic and diluted net income (loss) per share: Three Months Ended Nine Months Ended September 26, September 27, September 26, September 27, (in thousands, except per share amounts) 2015 2014 2015 2014 Numerator: Net income (loss) $ $ $ $ Denominator: Basic and diluted weighted average common shares outstanding (1) Dilutive effect of employee stock options and awards — Diluted weighted average common shares outstanding (1) Basic and diluted net income (loss) per share $ $ $ $ (1) PMC-Sierra Ltd. special shares are included in the calculation of basic and diluted weighted average common shares outstanding. In the nine months ended September 27, 2014 , the Company had approximately 3.3 million of stock options and Restricted Stock Units that were not included in the diluted net loss per share because they would have been anti-dilutive.

Stock Repurchase

Stock Repurchase	9 Months Ended
	Sep. 26, 2015
Stock Repurchase [Abstract]
Stock Repurchase	NOTE 11. Stock Repurchase On February 9, 2015, the Board of Directors of the Company authorized a share repurchase for up to $75 million of its common stock. This program increased the total remaining repurchase authorization to $102.1 million, including the $27.1 million that remained available for repurchases under the $275 million 2012 share repurchase authorization as of December 27, 2014. On May 21, 2015, the Board of Directors of the Company authorized up to $75 million of its common stock for share repurchases, which is the authorization amount that remained available for repurchases as of September 26, 2015. For the nine months ended September 26, 2015 and September 27, 2014 , the Company repurchased 11.6 million and 1.4 million shares for a total cash cost of $102.1 million and $8.9 million, respectively. The repurchased shares were retired immediately. Accordingly, the repurchased shares were recorded as a reduction of common stock, additional paid-in capital and accumulated deficit. As of September 26, 2015 , the Company had completed $430.0 million of the total announced $505.0 million stock repurchases since 2011.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 26, 2015
Subsequent Events [Abstract]
Subsequent Events	NOTE 12. Subsequent Events On October 5, 2015 , the Company entered into an Agreement and Plan of Merger with Skyworks Solutions, Inc., a Delaware corporation (“Parent” or “Skyworks”), and Amherst Acquisition, Inc., a Delaware corporation and a wholly owned subsidiary of Parent (“Merger Sub”) , which agreement was later amended and restated by the parties’ entry into the Amended and Restated Agreement and Plan of Merger on October 29, 2015 (as so amended and restated, the “Merger Agreement’) in response to an unsolicited bid from Microsemi Corporation. Under the Merger Agreement, Skyworks has agreed to acquire the Company for $11.60 in cash per share of the Company’s common stock. Upon the terms and subject to the conditions of the Merger Agreement, Merger Sub will merge with and into the Company (the “Merger”), with the Company surviving the Merger as a wholly-owned subsidiary of Parent. In the Merger, each outstanding share of the Company’s common stock (the “ Company Common Stock ”), other than shares of Company Common Stock held in the treasury of the Company, shares of Company Common Stock owned by Parent or any subsidiary of Parent (including Merger Sub) or shares of Common Stock owned by stockholders who have validly exercised their appraisal rights under Delaware law, will be converted into the right to receive $11.60 per share in cash (the “Merger Consideration”) without interest and subject to any required withholding for taxes. Skyworks intends to fund the Merger Consideration with a combination of cash on hand and committed debt financing. As a result of the Merger, (i) each vested in-the-money stock option and vested restricted stock unit will be cancelled in exchange for the right to receive the Merger Consideration (less any amounts required to be withheld and, in the case of options, the exercise price of such options), and (ii) each unvested stock option, out-of-the money stock option (whether vested or unvested) and unvested restricted stock unit (including unvested performance stock units, with target-level performance deemed achieved) will be assumed by Parent and converted, as applicable, into stock options and restricted stock units of Parent, on the basis of the Merger Consideration, adjusted pursuant to an exchange ratio based on Company and Parent’s relative stock price s prior to the Merger, which converted stock options and restricted stock units shall retain the same vesting terms (except that performance stock units will be subject only to time-based vesting conditions following the Merger). Closing Conditions The obligation of each party to consummate the Merger is subject to the satisfaction or waiver of customary closing conditions set forth in the Merger Agreement, including (i) the approval of the Merger Agreement and the Merger by stockholders of the Company owning at least a majority of the issued and outstanding shares of Company Common Stock, (ii) the expiration or termination of any applicable regulatory waiting periods and/or receipt of regulatory clearance, (iii) the absence of any order or ruling prohibiting the consummation of the Merger and (iv) subject to certain exceptions, the accuracy of the other party’s representations and warranties and compliance with covenants. In addition, the obligation of Parent and Merger Sub to consummate the Merger is also subject to the satisfaction or waiver of the condition that no material adverse effect on the Company shall have occurred since the date of the Merger Agreement. Skyworks’ and the Company’s obligations are not subject to any financing condition. Representations and Warranties; Covenants Each of the Company, Parent and Merger Sub has made customary representations and warranties and covenants in the Merger Agreement, including covenants to use their respective reasonable best efforts to secure required regulatory approvals , other than antitrust filings, which are governed by more detailed requirements . In addition, the Company has agreed to other customary covenants, including, among others, covenants to conduct its business in the ordinary course during the interim period between the execution of the Merger Agreement and the closing of the Merger, and not to solicit alternative transactions or, subject to certain exceptions, not to enter into discussions concerning, or provide confidential information in connection with, an alternative transaction, and Parent has agreed to other customary covenants, including, among others, covenants to use i t s reasonable best efforts to consummate the committed debt financing. Termination and Termination Fees The Merger Agreement contains certain termination rights for each of the Company and Parent, including, among others, if the Merger is not consummated at or prior to 11:59 p.m. (New York City time ) on July 6, 2016 , which may be extended by either the Company or Parent until October 5, 2016 if the mutual closing conditions set forth in the Merger Agreement relating to regulatory clearances have not yet been satisfied or waived. Upon termination of the Merger Agreement under sp ecified circumstances, including a termination by the Company to enter into an agreement for an alternative transaction pursuant to a “superior proposal,” the Company has agreed to pay Parent a termination fee of $ 88.5 million. The Company recorded acquisition-related costs of approximately $1.6 million, primarily for outside legal and financial advisory fees associated with the pending Skyworks acquisition of the Company in the three and nine months ended September 26, 2015. Those costs were recorded in selling, general and administrative expenses in our unaudited Condensed Consolidated Statements of Operations for the three and nine months ended September 26, 2015. The foregoing description of the Merger Agreement and the transactions contemplated thereby does not purport to be complete and is subject to, and qualified in its entirety by, the full text of the Amended and Restated Merger Agreement, which is attached as Exhibit 2.1 to the Form 8-K filed by the Company on October 30 , 2015 and listed in the Exhibit Table of this filing. The Company plans to file with the SEC and mail to our stockholders a proxy statement in connection with the Merger. Additionally, the Company intends to file other relevant materials with the SEC in connection with the Merger. The proxy statement and other relevant materials will contain important information about the Company, Skyworks, the Merger and related matters. Investors and stockholders are urged to read the proxy statement and the other relevant materials carefully when they become available before making any voting or investment decision with respect to the Merger.

Summary Of Significant Accoun20

Summary Of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 26, 2015
Summary Of Significant Accounting Policies [Abstract]
Description Of Business	Description of business . PMC-Sierra, Inc. (the “Company” or “PMC”) is a fabless semiconductor and software solution innovator transforming networks that connect, move, and store Big Data. The Company designs, develops, markets and supports semiconductor, embedded software, and board level solutions by integrating its mixed-signal, software and systems expertise through a network of offices in North America, Europe and Asia. Building on a track record of technology leadership, the Company is driving innovation across storage, optical and mobile networks. PMC ’ s highly integrated solutions increase performance and enable next generation services to accelerate the network transformation.
Basis Of Presentation	Basis of presentation. The accompanying interim condensed consolidated financial statements have been prepared pursuant to the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) and United States Generally Accepted Accounting Principles (“GAAP”). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to those rules or regulations. These interim condensed consolidated financial statements are unaudited, but reflect all adjustments which are normal and recurring in nature and are, in the opinion of management, necessary to provide a fair statement of results for the interim periods presented. These interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes in the Company ’ s Annual Report on Form 10-K for the year ended December 27, 2014 filed with the SEC on February 24, 2015. The results of operations for the interim periods are not necessarily indicative of results to be expected in future periods. Fiscal 2015 will consist of 52 weeks and will end on Saturday, December 26, 2015. Fiscal 2014 consisted of 52 weeks and ended on Saturday, December 27, 2014. The third quarter of each of 2015 and 2014 consisted of 13 weeks. The Company’s reporting currency is the United States (“U.S.”) dollar and presented in thousands unless otherwise stated.
Estimates	Estimates . The preparation of financial statements and related disclosures in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Estimates are used for, but not limited to, stock-based compensation, purchase accounting assumptions including those used to calculate the fair value of intangible assets and goodwill, the valuation of investments, accounting for doubtful accounts, inventory reserves, depreciation and amortization, asset impairments, revenue recognition, sales returns, warranty costs, restructuring costs, income taxes including uncertain tax positions, accounting for employee benefit plans, and contingencies. Actual results could differ materially from these estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-03, Simplifying the Presentation of Debt Issuance Costs, which requires that debt issuance costs related to recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. This ASU requires retrospective adoption and will be effective for us beginning in our first quarter of 2017. Early adoption is permitted. ASU 2015-13 is not expected to have a material impact on the Company’s condensed consolidated financial statements. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers , or ASU 2014-09, which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The standard will replace most existing revenue recognition guidance in GAAP when it becomes effective. The standard allows for either full retrospective or modified retrospective adoption method. In July 2015, the FASB deferred the effective date to January 1, 2018 with early adoption beginning January 1, 2017. The Company is currently evaluating the effect that ASU 2014-09 will have on its consolidated financial statements and related disclosures. The Company has not yet selected a transition method, adoption date, or determined the effect of the standard on its ongoing financial reporting. In July 2015, the FASB issued ASU 2015-11, Inventory - Simplifying the Measurement of Inventory (Topic 330) . ASU 2015-11 requires inventory to be subsequently measured using the lower of cost and net realizable value, thereby eliminating the market value approach. Net realizable value is defined as the “estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation.” ASU 2015-11 is effective for reporting periods beginning after December 15, 2016 and is applied prospectively. Early adoption is permitted. We are currently evaluating the impact that this guidance will have on our financial statements and disclosure.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 26, 2015
Fair Value Measurements [Abstract]
Financial Assets Measured At Fair Value On Recurring Basis	Fair value, September 26, 2015 (in thousands) Level 1 Level 2 Assets: Money market funds $ $ — Corporate bonds and notes U.S. treasury and government agency notes — Foreign government and agency notes U.S. state and municipal securities Total assets $ $ Fair value, December 27, 2014 (in thousands) Level 1 Level 2 Assets: Money market funds $ $ — Corporate bonds and notes U.S. treasury and government agency notes Foreign government and agency notes U.S. state and municipal securities — Total assets $ $ These assets are included in Cash and cash equivalents, Short-term investments, and Long-term investment securities. See Note 7. Investment Securities .
Financial Liabilities Measured At Fair Value On Recurring Basis	Fair value, September 26, 2015 (in thousands) Level 2 Current liabilities: Forward currency contracts $ Fair value, December 27, 2014 (in thousands) Level 2 Current liabilities: Forward currency contracts $ These are included in Accrued liabilities.

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 26, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule Of Stock-Based Compensation Expense	Three Months Ended Nine Months Ended September 26, September 27, September 26, September 27, (in thousands) 2015 2014 2015 2014 Cost of revenues $ $ $ $ Research and development, net Selling, general and administrative Total $ $ $ $
Schedule Of Activity Under Option Plans	Number of options Weighted average exercise price per share Weighted average remaining contractual term (years) Aggregate intrinsic value Outstanding, December 27, 2014 $ $ Granted $ Exercised $ Forfeited $ Expired $ Outstanding, September 26, 2015 $ $ Vested and expected to vest, September 26, 2015 $ $ Exercisable, September 26, 2015 $ $
Schedule Of Fair Value Weighted Average Assumptions	Nine Months Ended September 26, September 27, 2015 2014 Expected life (years) Expected volatility Risk-free interest rate
Summary Of RSU Activity	Restricted Stock Units Weighted Average Remaining Contractual Term (years) Aggregate intrinsic value Unvested units at December 27, 2014 $ Awarded - — Released - — Forfeited - — Unvested units at September 26, 2015 $ Restricted Stock Units expected to vest at September 26, 2015 $
2011 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Schedule Of Fair Value Weighted Average Assumptions	Nine Months Ended September 26, September 27, 2015 2014 Expected life (years) Expected volatility Risk-free interest rate

Balance Sheet Items (Tables)

Balance Sheet Items (Tables)	9 Months Ended
	Sep. 26, 2015
Balance Sheet Items [Abstract]
Schedule Of Inventories	September 26, December 27, (in thousands) 2015 2014 Work-in-progress $ $ Finished goods $ $
Schedule Of Product Warranties	Nine Months Ended September 26, September 27, (in thousands) 2015 2014 Balance, beginning of the period $ $ Accrual for new warranties issued Reduction for payments and product replacements Adjustments related to revisions and changes in estimate of warranty accrual Balance, end of the period $ $
Schedule Of Restructuring Costs	Three Months Ended Nine Months Ended September 26, September 26, (in thousands) 2015 2015 Employee severance and related compensation benefits (recoveries) expense: Cost of revenues $ $ Research and development, net Selling, general and administrative Site closures and asset impairments Total restructuring costs $ $
Schedule Of Restructuring Activity	(in thousands) Employee severance & related benefits compensation Site closures & assets impairment Total Accrued restructuring balance as of December 27, 2014 $ — $ — $ — Additional accruals Cash payments Adjustments and non-cash charges Accrued restructuring balance as of September 26, 2015 $ $ $

Investment Securities (Tables)

Investment Securities (Tables)	9 Months Ended
	Sep. 26, 2015
Investment Securities [Abstract]
Available For Sale Investments	September 26, 2015 (in thousands) Amortized Cost Gross Unrealized Gains* Gross Unrealized Losses Fair Value Cash equivalents: Money market funds $ $ — $ — $ Total cash equivalents — — Short-term investments: Corporate bonds and notes US treasury and government agency notes — Foreign government and agency notes US states and municipal securities — Total short-term investments Long-term investment securities: Corporate bonds and notes US treasury and government agency notes Foreign government and agency notes Total long-term investment securities Total $ $ $ $ * Gross unrealized gains include accrued interest on investments of $0.6 million which are included in the Consolidated Statement of Operations. The remainder of the gross unrealized gains and losses are included in the Consolidated Balance Sheet as Accumulated other comprehensive income (loss). December 27, 2014 (in thousands) Amortized Cost Gross Unrealized Gains* Gross Unrealized Losses Fair Value Cash equivalents: Money market funds $ $ — $ — $ Total cash equivalents — — Short-term investments: Corporate bonds and notes US treasury and government agency notes — Foreign government and agency notes — Total short-term investments Long-term investment securities: Corporate bonds and notes US treasury and government agency notes Foreign government and agency notes US states and municipal securities — Total long-term investment securities Total $ $ $ $ *Gross unrealized gains include accrued interest on investments of $0.6 million which are included in the Consolidated Statement of Operations. The remainder of the gross unrealized gains and losses are included in the Consolidated Balance Sheet as Accumulated other comprehensive income (loss).

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 26, 2015
Net Loss Per Share [Abstract]
Computation Of Basic And Diluted Net Loss Per Share	Three Months Ended Nine Months Ended September 26, September 27, September 26, September 27, (in thousands, except per share amounts) 2015 2014 2015 2014 Numerator: Net income (loss) $ $ $ $ Denominator: Basic and diluted weighted average common shares outstanding (1) Dilutive effect of employee stock options and awards — Diluted weighted average common shares outstanding (1) Basic and diluted net income (loss) per share $ $ $ $ (1) PMC-Sierra Ltd. special shares are included in the calculation of basic and diluted weighted average common shares outstanding.

Business Combinations (Details)

Business Combinations (Details) - USD ($) $ in Thousands	Jan. 10, 2017	Jan. 10, 2016	Jan. 10, 2015	Sep. 04, 2014	Sep. 26, 2015	Sep. 26, 2015	Jun. 27, 2015
Business Acquisition [Line Items]
Installment payment						$ 18,000
RAID Software License [Member]
Business Acquisition [Line Items]
Effective Date						Sep. 4, 2014
Total acquisition consideration				$ 52,000
Initial payment				$ 10,000
Installment payment			$ 18,000
Installment payments remaining					$ 24,000	$ 24,000
Period for development of future generations of software						2 years
Cost reimbursement payments					25,000	$ 25,000
Reimbursement revenue					$ 3,300	$ 9,800	$ 13,800
Forecast [Member] | RAID Software License [Member]
Business Acquisition [Line Items]
Installment payment	$ 12,000	$ 12,000

Derivative Instruments (Details

Derivative Instruments (Details) - Cash Flow Hedging [Member]	3 Months Ended		9 Months Ended
	Sep. 26, 2015USD ($)contract	Sep. 27, 2014USD ($)contract	Sep. 26, 2015USD ($)contract	Sep. 27, 2014USD ($)contract
Derivative [Line Items]
Gains (losses) related to de-designation of discontinued cash flow hedges			$ 0
Forward currency contracts outstanding | contract	79	84	79	84
Forward currency contracts maturity, maximum			15 months
Notional amount of contracts	$ 48,300,000	$ 35,500,000	$ 48,300,000	$ 35,500,000
Aggregate fair value gain, net of taxes	$ 2,700,000	$ 700,000	$ 700,000	$ 200,000

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - USD ($)	Sep. 26, 2015	Dec. 27, 2014
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured and recorded at fair value	$ 0
Liabilities measured and recorded at fair value	0
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments previously listed as Level 2	(10,100,000)
Assets measured and recorded at fair value	149,969,000	$ 135,950,000
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments previously listed as Level 1	(9,500,000)
Assets measured and recorded at fair value	30,818,000	26,173,000
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets measured and recorded at fair value	0	0
Liabilities measured and recorded at fair value	$ 0	$ 0

Fair Value Measurements (Financ

Fair Value Measurements (Financial Assets Measured At Fair Value On Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 149,969	$ 135,950
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	4,040	8,729
Level 1 [Member] | Corporate Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	97,434	88,401
Level 1 [Member] | U.S. Treasury And Government Agency Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	46,835	38,283
Level 1 [Member] | Foreign Government And Agency Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	1,509	537
Level 1 [Member] | U.S. State And Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	151
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	30,818	26,173
Level 2 [Member] | Corporate Bonds And Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	21,224	17,030
Level 2 [Member] | U.S. Treasury And Government Agency Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets		1,387
Level 2 [Member] | Foreign Government And Agency Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	9,514	7,525
Level 2 [Member] | U.S. State And Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 80	$ 231

Fair Value Measurements (Fina30

Fair Value Measurements (Financial Liabilities Measured At Fair Value On Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Forward currency contracts	$ 2,744	$ 1,907

Stock-Based Compensation (Narra

Stock-Based Compensation (Narrative) (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 26, 2015USD ($)$ / sharesShareBasedCompensationPlanshares	Sep. 27, 2014USD ($)$ / shares	Dec. 27, 2014shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation plans | ShareBasedCompensationPlan	2
Proceeds from issuance of common stock	$ 36,982	$ 17,924
2011 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation costs	$ 1,100
Average period of unrecognized compensation costs expected to be recognized	4 months
Common shares initially reserved for issuance | shares	2,653,049		4,380,208
Common shares increase | shares	7,000,000
Shares issued during period under ESPP | shares	1,727,159
Weighted average price per share under ESPP | $ / shares	$ 5.91
Weighted average grant-date fair value per ESPP award | $ / shares	$ 1.93
Total intrinsic value of ESPP shares issued	$ 3,700
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration period	10 years
Options vesting period	4 years
Total forfeitures recorded	$ 700	$ 1,800
Weighted average grant-date fair value per stock options granted | $ / shares	$ 2.11	$ 2.29
Total intrinsic value of awards	$ 9,600	$ 2,300
Total unrecognized compensation costs	$ 3,500
Average period of unrecognized compensation costs expected to be recognized	2 years 10 months 24 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of awards	$ 14,900
Total unrecognized compensation costs	$ 41,000
Average period of unrecognized compensation costs expected to be recognized	2 years 9 months 18 days
Restricted Stock Units (RSUs) [Member] | February 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of grants	$ 3,800
Restricted Stock Units (RSUs) [Member] | August 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of grants	$ 1,500
Restricted Stock Units (RSUs) [Member] | First Vesting Date [Member] | February 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	34.00%
Restricted Stock Units (RSUs) [Member] | First Vesting Date [Member] | August 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Restricted Stock Units (RSUs) [Member] | Second Vesting Date [Member] | February 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Restricted Stock Units (RSUs) [Member] | Second Vesting Date [Member] | August 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Restricted Stock Units (RSUs) [Member] | Third Vesting Date [Member] | February 25, 2015 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	33.00%
Maximum [Member] | 2011 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares initially reserved for issuance | shares	12,000,000

Stock-Based Compensation (Sched

Stock-Based Compensation (Schedule Of Stock-Based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 5,190	$ 5,228	$ 17,994	$ 16,334
Cost Of Revenues [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	266	226	803	681
Research And Development, Net [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	2,266	1,990	7,510	6,540
Selling, General And Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 2,658	$ 3,012	$ 9,681	$ 9,113

Stock-Based Compensation (Sch33

Stock-Based Compensation (Schedule Of Activity Under Option Plans) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 26, 2015	Dec. 27, 2014
Stock-Based Compensation [Abstract]
Outstanding beginning balance, Number of options	18,316,720
Granted, Number of options	847,892
Exercised, Number of options	(4,017,595)
Forfeited, Number of options	(136,344)
Expired, Number of options	(1,025,118)
Outstanding ending balance, Number of options	13,985,555	18,316,720
Vested and expected to vest, Number of options	13,731,955
Exercisable, Number of options	12,046,856
Outstanding beginning balance, Weighted average exercise price per share	$ 7.53
Granted, Weighted average exercise price per share	6.73
Exercised, Weighted average exercise price per share	6.66
Forfeited, Weighted average exercise price per share	6.55
Expired, Weighted average exercise price per shre	9.48
Outstanding ending balance, Weighted average exercise price per share	7.60	$ 7.53
Vested and expected to vest, Weighted average exercise price per share	7.62
Exercisable, Weighted average exercise price per share	$ 7.75
Outstanding, Weighted average remaining contractual term (years)	4 years 3 months 7 days	4 years 4 months 28 days
Vested and expected to vest, Weighted average remaining contractual term (years)	4 years 2 months 5 days
Exercisable, Weighted average remaining contractual term (years)	3 years 6 months 11 days
Outstanding beginning balance, Aggregate intrinsic value	$ 32,598,999
Outstanding ending balance, Aggregate intrinsic value	2,734,065	$ 32,598,999
Vested and expected to vest, Aggregate intrinsic value	2,722,645
Exercisable, Aggregate intrinsic value	$ 2,509,015

Stock-Based Compensation (Sch34

Stock-Based Compensation (Schedule Of Fair Value Weighted Average Assumptions) (Details)	9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)	5 years 10 months 24 days	5 years 9 months 18 days
Expected volatility	30.00%	33.00%
Risk-free interest rate	1.80%	1.80%
2011 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (years)	6 months	6 months
Expected volatility	34.00%	35.00%
Risk-free interest rate	0.20%	0.10%

Stock-Based Compensation (Summa

Stock-Based Compensation (Summary Of RSU Activity) (Details) - Restricted Stock Units (RSUs) [Member] - USD ($)	9 Months Ended	12 Months Ended
	Sep. 26, 2015	Dec. 27, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested units, Beginning balance, Restricted Stock Units	7,368,529
Awarded, Restricted Stock Units	3,492,249
Released, Restricted Stock Units	(2,242,344)
Forfeited, Restricted Stock Units	(712,317)
Unvested units, Ending balance, Restricted Stock Units	7,906,117	7,368,529
Restricted Stock Units expected to vest, Restricted Stock Units	6,784,932
Unvested units, Weighted Average Remaining Contractual Term (years)	1 year 9 months 29 days	1 year 8 months 23 days
Restricted Stock Units expected to vest, Weighted Average Remaining Contractual Term (years)	1 year 8 months 23 days
Unvested units, Beginning balance, Aggregate intrinsic value	$ 67,200,984
Unvested units, Ending balance, Aggregate intrinsic value	50,361,965	$ 67,200,984
Restricted Stock Units expected to vest, Aggregate intrinsic value	$ 43,220,018

Balance Sheet Items (Schedule O

Balance Sheet Items (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Sep. 26, 2015	Dec. 27, 2014
Balance Sheet Items [Abstract]
Work-in-progress	$ 15,655	$ 17,438
Finished goods	17,191	20,511
Inventory, net	32,846	37,949
Inventory reserves	$ 7,200	$ 7,800

Balance Sheet Items (Schedule37

Balance Sheet Items (Schedule Of Product Warranties) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014
Balance Sheet Items [Abstract]
Balance, beginning of the period	$ 1,756	$ 2,163
Accrual for new warranties issued	512	371
Reduction for payments and product replacements	(372)	(533)
Adjustments related to revisions and changes in estimate of warranty accrual	(700)	(113)
Balance, end of the period	$ 1,196	$ 1,888

Balance Sheet Items (Schedule38

Balance Sheet Items (Schedule Of Restructuring Costs) (Details) $ in Thousands	3 Months Ended	9 Months Ended	21 Months Ended
	Sep. 26, 2015USD ($)	Sep. 26, 2015USD ($)employee	Dec. 25, 2016USD ($)
Restructuring Cost and Reserve [Line Items]
Number of employees, reduction in force | employee		200
Employee severance and related compensation benefits	$ (70)	$ 13,015
Site closures and asset impairments	1,165	1,165
Total restructuring costs	1,095	14,180
Cost Of Revenues [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and related compensation benefits	(6)	1,158
Research And Development, Net [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and related compensation benefits	(80)	7,864
Selling, General And Administrative [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and related compensation benefits	$ 16	$ 3,993
Forecast [Member]
Restructuring Cost and Reserve [Line Items]
Site closures and asset impairments			$ 2,000
Minimum [Member] | Forecast [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and related compensation benefits			13,000
Total restructuring costs			15,000
Maximum [Member] | Forecast [Member]
Restructuring Cost and Reserve [Line Items]
Employee severance and related compensation benefits			14,000
Total restructuring costs			$ 16,000

Balance Sheet Items (Schedule39

Balance Sheet Items (Schedule Of Restructuring Activity) (Details) $ in Thousands	9 Months Ended
	Sep. 26, 2015USD ($)
Restructuring Cost and Reserve [Line Items]
Accrued restructuring beginning balance
Additional accruals	$ 14,653
Cash payments	(6,281)
Adjustments and non-cash charges	(1,713)
Accrued restructuring ending balance	$ 6,659
Employee Severance & Related Benefits Compensation [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring beginning balance
Additional accruals	$ 13,488
Cash payments	(6,127)
Adjustments and non-cash charges	(921)
Accrued restructuring ending balance	$ 6,440
Site Closures & Assets Impairment [Member]
Restructuring Cost and Reserve [Line Items]
Accrued restructuring beginning balance
Additional accruals	$ 1,165
Cash payments	(154)
Adjustments and non-cash charges	(792)
Accrued restructuring ending balance	$ 219

Investment Securities (Narrativ

Investment Securities (Narrative) (Details)	9 Months Ended
	Sep. 26, 2015
Contractual maturities of investment securities	3 years
Minimum [Member]
Contractual maturities of investment securities	2 years
Maximum [Member]
Contractual maturities of investment securities	3 years
Contractual maturities of investment securities, balance	1 year

Investment Securities (Availabl

Investment Securities (Available For Sale Investments) (Details) - USD ($) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 26, 2015	Dec. 27, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 179,628	$ 161,817
Gross Unrealized Gains	[1]	1,286	650
Gross Unrealized Losses		(127)	(344)
Fair Value		180,787	162,123
Accrued interest on investments		600	600
Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,040	8,729
Fair Value		4,040	8,729
Cash Equivalents [Member] | Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,040	8,729
Fair Value		4,040	8,729
Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		41,252	45,288
Gross Unrealized Gains	[1]	1,102	613
Gross Unrealized Losses		(7)	(16)
Fair Value		42,347	45,885
Short-Term Investments [Member] | Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		32,879	43,777
Gross Unrealized Gains	[1]	958	498
Gross Unrealized Losses		(5)	(16)
Fair Value		33,832	44,259
Short-Term Investments [Member] | U.S. Treasury And Government Agency Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		5,131	1,010
Gross Unrealized Gains	[1]	92	79
Fair Value		5,223	1,089
Short-Term Investments [Member] | Foreign Government And Agency Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		3,012	501
Gross Unrealized Gains	[1]	51	36
Gross Unrealized Losses		(2)
Fair Value		3,061	537
Short-Term Investments [Member] | US States And Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		230
Gross Unrealized Gains	[1]	1
Fair Value		231
Long-Term Investment Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		134,336	107,800
Gross Unrealized Gains	[1]	184	37
Gross Unrealized Losses		(120)	(328)
Fair Value		134,400	107,509
Long-Term Investment Securities [Member] | Corporate Bonds And Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		84,866	61,357
Gross Unrealized Gains	[1]	75	28
Gross Unrealized Losses		(115)	(213)
Fair Value		84,826	61,172
Long-Term Investment Securities [Member] | U.S. Treasury And Government Agency Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		41,508	38,650
Gross Unrealized Gains	[1]	105	7
Gross Unrealized Losses		(1)	(76)
Fair Value		41,612	38,581
Long-Term Investment Securities [Member] | Foreign Government And Agency Notes [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		7,962	7,563
Gross Unrealized Gains	[1]	4	1
Gross Unrealized Losses		(4)	(39)
Fair Value		$ 7,962	7,525
Long-Term Investment Securities [Member] | US States And Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost			230
Gross Unrealized Gains	[1]		1
Fair Value			$ 231
[1]	Gross unrealized gains include accrued interest on investments of $0.6 million which are included in the Consolidated Statement of Operations. The remainder of the gross unrealized gains and losses are included in the Consolidated Balance Sheet as Accumulated other comprehensive income (loss).

Credit Facility (Details)

Credit Facility (Details) - USD ($) $ in Thousands	Oct. 14, 2015	Sep. 26, 2015	Sep. 27, 2014	Dec. 27, 2014
Line of Credit Facility [Line Items]
Line of credit, repayment of outstanding balance		$ 72,000	$ 60,000
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity		100,000
Line of credit, amount drawn		$ 30,000		$ 0
Subsequent Event [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit, repayment of outstanding balance	$ 5,000
Minimum [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit, margin rate		1.75%
Maximum [Member] | Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity		$ 150,000
Line of credit, margin rate		2.25%

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014	Dec. 27, 2014
Income Taxes [Abstract]
Provision for income taxes	$ 6,727	$ 3,087	$ 7,943	$ 9,405
Effective tax rate	50.00%	36.00%	74.00%	131.00%
Federal statutory rate	35.00%	35.00%	35.00%	35.00%
Unrecognized tax benefits	$ 41,100		$ 41,100		$ 41,300

Net Loss Per Share (Computation

Net Loss Per Share (Computation Of Basic And Diluted Net Loss Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Net Loss Per Share [Abstract]
Net income (loss)		$ 6,718	$ 5,473	$ 2,794	$ (2,248)
Basic and diluted weighted average common shares outstanding	[1]	194,562	197,613	196,848	196,305
Dilutive effect of employee stock options and awards		2,303	3,131	4,170
Diluted weighted average common shares outstanding	[1]	196,865	200,744	201,018	196,305
Basic and diluted net income (loss) per share		$ 0.03	$ 0.03	$ 0.01	$ (0.01)
Antidilutive securities excluded from computation of loss per share					3,300,000
[1]	PMC-Sierra Ltd. special shares are included in the calculation of basic and diluted weighted average common shares outstanding.

Stock Repurchase (Details)

Stock Repurchase (Details) - USD ($) shares in Millions, $ in Millions	9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	May. 21, 2015	Feb. 09, 2015	Dec. 27, 2014
Equity, Class of Treasury Stock [Line Items]
Share repurchase plan, authorized amount	$ 505		$ 75	$ 75
Share repurchase plan, remaining authorized amount				102.1
Share repurchase plan, authorized amount available	$ 430
Share repurchase plan, common stock repurchased, shares	11.6	1.4
Share repurchase plan, common stock repurchased, value	$ 102.1	$ 8.9
2012 Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Share repurchase plan, authorized amount					$ 275
Share repurchase plan, remaining authorized amount				$ 27.1

Subsequent Events (Details)

Subsequent Events (Details) - Skyworks And Merger Sub [Member] - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 26, 2015	Oct. 29, 2015	Oct. 05, 2015
Subsequent Event [Line Items]
Date of Merger Agreement	Oct. 5, 2015
Consummation date of Merger Agreement	Jul. 6, 2016
Extension date of Merger Agreement	Oct. 5, 2016
Acquisition-related costs	$ 1.6
Subsequent Event [Member]
Subsequent Event [Line Items]
Merger Consideration price per share		$ 11.60
Conditional termination fee			$ 88.5