Infinera (INFN) 10-Q 4 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 26, 2016	Apr. 27, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 26, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1
Trading Symbol	INFN
Entity Registrant Name	INFINERA CORP
Entity Central Index Key	1,138,639
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)		141,465,906

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Current assets:
Cash and cash equivalents	$ 179,974	$ 149,101
Short-term investments	95,116	125,561
Accounts receivable, net of allowance for doubtful accounts of $630 in 2016 and $630 in 2015	184,309	186,243
Inventory	189,744	174,699
Prepaid expenses and other current assets	29,689	29,511
Total current assets	678,832	665,115
Property, plant and equipment, net	115,372	110,861
Intangible assets	151,311	156,319
Goodwill	193,498	191,560
Long-term investments	80,488	76,507
Cost-method investment	14,500	14,500
Long-term restricted cash	5,331	5,310
Other non-current assets	4,032	4,009
Total assets	1,243,364	1,224,181
Current liabilities:
Accounts payable	83,035	92,554
Accrued expenses	33,319	33,736
Accrued compensation and related benefits	34,572	49,887
Accrued warranty	17,663	17,889
Deferred revenue	48,285	42,977
Total current liabilities	216,874	237,043
Long-term debt, net	125,796	123,327
Accrued warranty, non-current	22,336	20,955
Deferred revenue, non-current	18,391	13,881
Deferred tax liability	35,436	35,731
Other long-term liabilities	$ 18,528	$ 16,183
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value Authorized shares – 25,000 and no shares issued and outstanding	$ 0	$ 0
Issued and outstanding shares – 141,425 as of March 26, 2016 and 140,197 as of December 26, 2015	141	140
Additional paid-in capital	1,313,783	1,300,301
Accumulated other comprehensive income	4,774	1,123
Accumulated deficit	(527,398)	(539,413)
Total Infinera Corporation stockholders’ equity	791,300	762,151
Noncontrolling interest	14,703	14,910
Total stockholders' equity	806,003	777,061
Total liabilities and stockholders’ equity	$ 1,243,364	$ 1,224,181

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Statement of Financial Position [Abstract]
Net of allowance for doubtful accounts	$ 630	$ 630
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, authorized shares (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	141,425,000	140,197,000
Common stock, shares outstanding (in shares)	141,425,000	140,197,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Revenue:
Product	$ 216,082	$ 160,843
Services	28,736	26,019
Total revenue	244,818	186,862
Cost of revenue:
Cost of product	118,062	89,506
Cost of services	10,418	9,244
Total cost of revenue	128,480	98,750
Gross profit	116,338	88,112
Operating expenses:
Research and development	54,145	39,257
Sales and marketing	30,009	21,042
General and administrative	17,313	12,656
Total operating expenses	101,467	72,955
Income from operations	14,871	15,157
Other income (expense), net:
Interest income	522	414
Interest expense	(3,155)	(2,890)
Other gain (loss), net	(214)	301
Total other income (expense), net	(2,847)	(2,175)
Income before income taxes	12,024	12,982
Provision for income taxes	216	616
Net income	11,808	12,366
Less: Loss attributable to noncontrolling interest	(207)	0
Net income attributable to Infinera Corporation	$ 12,015	$ 12,366
Net income per common share attributable to Infinera Corporation:
Basic (in usd per share)	$ 0.09	$ 0.10
Diluted (in usd per share)	$ 0.08	$ 0.09
Weighted average shares used in computing net income per common share:
Basic (in shares)	140,805	127,840
Diluted (in shares)	146,880	137,304

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Statement of Comprehensive Income [Abstract]
Loss attributable to noncontrolling interest	$ 11,808	$ 12,366
Other comprehensive income:
Unrealized gain on available-for-sale investments	383	267
Foreign currency translation adjustment	3,268	(159)
Net change in accumulated other comprehensive income	3,651	108
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	(207)	0
Comprehensive income attributable to Infinera Corporation	$ 15,252	$ 12,474

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Statement of Cash Flows [Abstract]
Loss attributable to noncontrolling interest	$ 11,808	$ 12,366
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	14,666	6,586
Amortization of debt discount and issuance costs	2,469	2,234
Amortization of premium on investments	481	954
Stock-based compensation expense	7,987	7,208
Other gain	0	(19)
Changes in assets and liabilities:
Accounts receivable	2,165	23,391
Inventory	(16,155)	(12,103)
Prepaid expenses and other assets	(274)	1,141
Accounts payable	(9,041)	(10,317)
Accrued liabilities and other expenses	(15,036)	(12,895)
Deferred revenue	9,776	2,797
Accrued warranty	1,133	(1,501)
Net cash provided by operating activities	9,979	19,842
Cash Flows from Investing Activities:
Purchase of available-for-sale investments	(37,393)	(80,022)
Proceeds from sales of available-for-sale investments	0	2,001
Proceeds from maturities of investments	63,759	91,280
Purchase of property and equipment	(10,844)	(7,367)
Change in restricted cash	(30)	352
Net cash provided by investing activities	15,492	6,244
Cash Flows from Financing Activities:
Proceeds from issuance of common stock	7,787	10,131
Minimum tax withholding paid on behalf of employees for net share settlement	(2,444)	(3,950)
Net cash provided by financing activities	5,343	6,181
Effect of exchange rate changes on cash	59	(139)
Net change in cash and cash equivalents	30,873	32,128
Cash and cash equivalents at beginning of period	149,101	86,495
Cash and cash equivalents at end of period	179,974	118,623
Supplemental disclosures of cash flow information:
Cash paid for income taxes, net of refunds	1,554	897
Cash paid for interest	37	0
Supplemental schedule of non-cash investing activities:
Transfer of inventory to fixed assets	$ 1,409	$ 1,403

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 26, 2016
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Basis of Presentation Infinera Corporation (the "Company") prepared its interim condensed consolidated financial statements that accompany these notes in conformity with U.S. generally accepted accounting principles ("U.S. GAAP") and pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the "SEC"), consistent in all material respects with those applied in the Company’s Annual Report on Form 10-K for the fiscal year ended December 26, 2015. The Company has made certain estimates, assumptions and judgments that can affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the condensed consolidated financial statements, as well as the reported amounts of revenue and expenses during the periods presented. Significant estimates, assumptions and judgments made by management include revenue recognition, stock-based compensation, inventory valuation, accrued warranty, business combinations, fair value measurement of investments and accounting for income taxes. Other estimates, assumptions and judgments made by management include allowances for sales returns, allowances for doubtful accounts, useful life of intangible assets, property, plant and equipment, and fair value measurement of the liability component of the Company's $150.0 million of 1.75% convertible senior notes due June 1, 2018 (the "Notes"). Management believes that the estimates and judgments upon which they rely are reasonable based upon information available to them at the time that these estimates and judgments are made. To the extent there are material differences between these estimates and actual results, the Company’s condensed consolidated financial statements will be affected. The interim financial information is unaudited, but reflects all adjustments that are, in management’s opinion, necessary to provide a fair presentation of results for the interim periods presented. All adjustments are of a normal recurring nature. The condensed consolidated financial statements include the accounts of the Company and its wholly-owned and majority-owned subsidiaries. All intercompany balances and transactions have been eliminated. The Company reclassified certain amounts reported in previous periods to conform to the current presentation. This interim information should be read in conjunction with the consolidated financial statements in the Company’s Annual Report on Form 10-K for the fiscal year ended December 26, 2015. To date, a few of the Company’s customers have accounted for a significant portion of its revenue. For the three months ended March 26, 2016 , three customers individually accounted for 17% , 16% and 14% of the Company's total revenue, respectively, and for the corresponding period in 2015, two customers individually accounted for 18% and 16% of the Company's total revenue. There have been no material changes in the Company’s significant accounting policies for the three months ended March 26, 2016 as compare d to those disclosed in the Company’s Annual Report on Form 10-K for the fiscal year ended December 26, 2015.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 26, 2016
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2016, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update 2016-11, "Revenue Recognition (Topic 605) and Derivatives and Hedging (Topic 815): Rescission of SEC Guidance Because of Accounting Standards Updates 2014-09 and 2014-16 Pursuant to Staff Announcements at the March 3, 2016 EITF Meeting (SEC Update)") ("ASU 2016-11"), which rescinds various standards codified as part of Topic 605, Revenue Recognition in relation to the future adoption of Topic 606. These rescissions include changes to topics pertaining to revenue and expense recognition for freight Services in process, accounting for shipping and handling fees and costs and accounting for consideration given by a vendor to a customer. This guidance is effective for the Company in its first quarter of fiscal 2018 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-11 will have on its consolidated financial statements. In April 2016, the FASB issued Accounting Standards Update 2016-10, "Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing" ("ASU 2016-10"), to address the potential diversity in practice at initial application and cost; and the complexity of applying Topic 606, both at transition and on an ongoing basis related to identification of performance obligations and licensing arrangements. The new accounting guidance is effective for the Company in its first quarter of fiscal 2018 and early adoption permitted.The Company is currently evaluating the impact of adoption of this update on its consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-09, "Improvements to Employee Share-Based Payment Accounting") ("ASU 2016-09"), which includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements, including the income tax effects of share-based payments and accounting for forfeitures. This guidance is effective for the Company in its first quarter of fiscal 2017 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-09 will have on its consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-06, "Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments (a consensus of the Emerging Issues Task Force)" ("ASU 2016-06"), which applies to all entities that are issuers of or investors in debt instruments (or hybrid financial instruments that are determined to have a debt host) with embedded call (put) options, and requires that embedded derivatives be separated from the host contract and accounted for separately as derivatives if certain criteria are met. One criterion is that the economic characteristics and risks of the embedded derivatives are not clearly and closely related to the economic characteristics and risks of the host contract. This guidance is effective for the Company in its first quarter of fiscal 2017 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-06 will have on its consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update 2016-02, "Leases (Topic 842)" ("ASU 2016-02"), which amends the existing accounting standards for leases. The new standard requires lessees to record a right-of-use asset and a corresponding lease liability on the balance sheet (with the exception of short-term leases). For lessees, leases will continue to be classified as either operating or financing in the income statement. This guidance is effective for the Company in its first quarter of fiscal 2019 and early adoption is permitted. ASU 2016-02 is required to be applied with a modified retrospective approach and requires application of the new standard at the beginning of the earliest comparative period presented. The Company is currently evaluating the method and impact the adoption of ASU 2016-02 will have on its consolidated financial statements. In September 2015, the FASB issued Accounting Standards Update 2015-16, "Business Combinations and Simplifying the Accounting for Measurement-Period Adjustments" ("ASU 2015-16"), which eliminates the requirement for an acquirer in a business combination to account for measurement-period adjustments retrospectively. Instead, an acquirer will recognize a measurement-period adjustment during the period in which it determines the amount of the adjustment. The guidance is effective for the Company in its first quarter of fiscal 2016. The Company's adoption of ASU 2015-16 had no impact on the Company's financial position, results of operations or cash flow. In July 2015, the FASB issued Accounting Standards Update 2015-11, "Simplifying the Measurement of Inventory" ("ASU 2015-11"), to simplify the guidance on the subsequent measurement of inventory, excluding inventory measured using last-in, first-out or the retail inventory method. Under ASU 2015-11, inventory should be at the lower of cost and net realizable value. The new accounting guidance is effective for the Company in its first quarter of fiscal 2017 with early adoption permitted. The Company is currently evaluating the impact of the pending adoption of ASU 2015-11 on its consolidated financial statements. In April 2015, the FASB issued Accounting Standards Update 2015-03, "Simplifying the Presentation of Debt Issuance Costs" ("ASU 2015-03"), which changes the presentation of debt issuance costs in financial statements. ASU 2015-03 requires an entity to present such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. The Company has adopted ASU 2015-03 during the first quarter of 2016. The December 26, 2015 balance sheet was retrospectively adjusted to reclassify $2.1 million from other non-current assets to a reduction of the Notes payable liability. In May 2014, the FASB issued Accounting Standards Update 2014-09, "Revenue from Contracts from Customers" ("ASU 2014-09"). ASU 2014-09 provides a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. ASU 2014-09 will require an entity to recognize revenue when it transfers 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. This update creates a five-step model that requires entities to exercise judgment when considering the terms of the contract(s), which include (i) identifying the contract(s) with the customer; (ii) identifying the separate performance obligations in the contract; (iii) determining the transaction price; (iv) allocating the transaction price to the separate performance obligations; and (v) recognizing revenue when each performance obligation is satisfied. In July 2015, the FASB deferred the effective date for annual reporting periods beginning after December 15, 2017 (including interim reporting periods within those periods). Early adoption is permitted to the original effective date of December 15, 2016 (including interim reporting periods within those periods). ASU 2014-09 will be effective for the Company’s first quarter of 2018. The Company has the option to apply the provisions of ASU 2014-09 either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of applying this standard recognized at the date of initial application. The Company is currently evaluating the method and impact the adoption of ASU 2014-09 will have on its consolidated financial statements.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 26, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Pursuant to the accounting guidance for fair value measurements and its subsequent updates, fair value is defined as the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. When determining the fair value measurements for assets and liabilities required or permitted to be recorded at fair value, the Company considers the principal or most advantageous market in which it would transact and it considers assumptions that market participants would use when pricing the asset or liability. Valuation techniques used by the Company are based upon observable and unobservable inputs. Observable or market inputs reflect market data obtained from independent sources, while unobservable inputs reflect the Company’s assumptions about market participant assumptions based on the best information available. Observable inputs are the preferred source of values. These two types of inputs create the following fair value hierarchy: Level 1 – Quoted prices in active markets for identical assets or liabilities. Level 2 – Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-based valuation techniques for which all significant assumptions are observable in the market or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 – Prices or valuations that require management inputs that are both significant to the fair value measurement and unobservable. The Company measures its cash equivalents, foreign currency exchange forward contracts and marketable debt securities at fair value and classifies its investments in accordance with the fair value hierarchy. The Company’s money market funds and U.S. treasuries are classified within Level 1 of the fair value hierarchy and are valued based on quoted prices in active markets for identical securities. The Company classifies its certificates of deposit, commercial paper, U.S. agency notes, corporate bonds and foreign currency exchange forward contracts within Level 2 of the fair value hierarchy as follows: Certificates of Deposit The Company reviews market pricing and other observable market inputs for the same or similar securities obtained from a number of industry standard data providers. In the event that a transaction is observed for the same or similar security in the marketplace, the price on that transaction reflects the market price and fair value on that day. In the absence of any observable market transactions for a particular security, the fair market value at period end would be equal to the par value. These inputs represent quoted prices for similar assets or these inputs have been derived from observable market data. Commercial Paper The Company reviews market pricing and other observable market inputs for the same or similar securities obtained from a number of industry standard data providers. In the event that a transaction is observed for the same or similar security in the marketplace, the price on that transaction reflects the market price and fair value on that day and then follows a revised accretion schedule to determine the fair market value at period end. In the absence of any observable market transactions for a particular security, the fair market value at period end is derived by accreting from the last observable market price. These inputs represent quoted prices for similar assets or these inputs have been derived from observable market data accreted mathematically to par. U.S. Agency Notes The Company reviews trading activity and pricing for its U.S. agency notes as of the measurement date. When sufficient quoted pricing for identical securities is not available, the Company uses market pricing and other observable market inputs for similar securities obtained from a number of industry standard data providers. These inputs represent quoted prices for similar assets in active markets or these inputs have been derived from observable market data. Corporate Bonds The Company reviews trading activity and pricing for each of the corporate bond securities in its portfolio as of the measurement date and determines if pricing data of sufficient frequency and volume in an active market exists in order to support Level 1 classification of these securities. If sufficient quoted pricing for identical securities is not available, the Company obtains market pricing and other observable market inputs for similar securities from a number of industry standard data providers. In instances where multiple prices exist for similar securities, these prices are used as inputs into a distribution-curve to determine the fair market value at period end. Foreign Currency Exchange Forward Contracts As discussed in Note 5, "Derivative Instruments" to the Notes to Condensed Consolidated Financial Statements, the Company mainly holds non-speculative foreign exchange forward contracts to hedge certain foreign currency exchange exposures. The Company estimates the fair values of derivatives based on quoted market prices or pricing models using current market rates. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs including interest rate curves, credit risk, foreign exchange rates, and forward and spot prices for currencies. The following tables represent the Company’s fair value hierarchy for its assets and liabilities measured at fair value on a recurring basis (in thousands): As of March 26, 2016 As of December 26, 2015 Fair Value Measured Using Fair Value Measured Using Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets Money market funds $ 61,077 $ — $ — $ 61,077 $ 37,829 $ — $ — $ 37,829 Certificates of deposit — 3,565 — 3,565 — 5,001 — 5,001 Commercial paper — 8,980 — 8,980 — 10,997 — 10,997 Corporate bonds — 120,002 — 120,002 — 163,400 — 163,400 U.S. agency notes — 10,761 — 10,761 — 10,717 — 10,717 U.S. treasuries 39,289 — — 39,289 24,851 — — 24,851 Foreign currency exchange forward contracts — 325 — 325 — 490 — 490 Total assets $ 100,366 $ 143,633 $ — $ 243,999 $ 62,680 $ 190,605 $ — $ 253,285 Liabilities Foreign currency exchange forward contracts $ — $ (16 ) $ — $ (16 ) $ — $ (44 ) $ — $ (44 ) During the three months ended March 26, 2016, there were no transfers of assets or liabilities between Level 1 and Level 2 of the fair value hierarchy. Investments at fair value were as follows (in thousands): March 26, 2016 Adjusted Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Money market funds $ 61,077 $ — $ — $ 61,077 Certificates of deposit 3,560 5 — 3,565 Commercial paper 8,985 — (5 ) 8,980 Corporate bonds 120,097 23 (118 ) 120,002 U.S. agency notes 10,786 — (25 ) 10,761 U.S. treasuries 39,293 12 (16 ) 39,289 Total available-for-sale investments $ 243,798 $ 40 $ (164 ) $ 243,674 December 26, 2015 Adjusted Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Money market funds $ 37,829 $ — $ — $ 37,829 Certificates of deposit 5,000 1 — 5,001 Commercial paper 10,997 — — 10,997 Corporate bonds 163,797 — (397 ) 163,400 U.S. agency notes 10,786 — (69 ) 10,717 U.S. treasuries 24,894 — (43 ) 24,851 Total available-for-sale investments $ 253,303 $ 1 $ (509 ) $ 252,795 As of March 26, 2016 , the Company’s available-for-sale investments in certificates of deposit, commercial paper, U.S. agency notes and corporate bonds have a contractual maturity term of up to 22 months . Gross realized gains and losses on short-term and long-term investments for the three months ended March 26, 2016 and March 28, 2015 were insignificant in both periods. The specific identification method is used to account for gains and losses on available-for-sale investments. As of March 26, 2016 and December 26, 2015, the Company held $111.9 million and $98.4 million of cash in banks, respectively, excluding restricted cash.

Cost-method Investment

Cost-method Investment	3 Months Ended
	Mar. 26, 2016
Investments, All Other Investments [Abstract]
Cost-method Investment	Cost-method Investment As of March 26, 2016 , the Company had an investment of $14.5 million in a privately-held company. This investment is accounted for as a cost-method investment as the Company owns less than 20% of the voting securities and does not have the ability to exercise significant influence over operating and financial policies of the entity. This investment is carried at historical cost in the Company's condensed consolidated financial statements. The Company regularly evaluates the carrying value of this cost-method investment for impairment. If the Company believes that the carrying value of the cost basis investment is in excess of estimated fair value, the Company’s policy is to record an impairment charge in other income (expense), net, in the accompanying condensed consolidated statements of operations to adjust the carrying value to estimated fair value, when the impairment is deemed other-than-temporary. As of March 26, 2016 , no event had occurred that would adversely affect the carrying value of this investment and thus no impairment charges have been recorded for this cost-method investment.

Derivative Instruments

Derivative Instruments	3 Months Ended
	Mar. 26, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments Foreign Currency Exchange Forward Contracts The Company enters into foreign currency exchange forward contracts to manage its exposure to fluctuations in foreign exchange rates that arise primarily from its euro and British pound denominated receivables and euro denominated restricted cash balance amounts that are pledged as collateral for certain stand-by and commercial letters of credit. Gains and losses on these contracts are intended to offset the impact of foreign exchange rate fluctuations on the underlying foreign currency denominated accounts receivables and restricted cash, and therefore, do not subject the Company to material balance sheet risk. These forward contracts entered into during the three months ended March 26, 2016 were denominated in euros and British pounds, and had maturities of no more than 1 year . The contracts are settled for U.S. dollars and Swedish kronor at maturity and at rates agreed to at inception of the contracts. For the three months ended March 26, 2016 and March 28, 2015, the before-tax effect of the foreign currency exchange forward contracts related to the euro and British pound denominated receivables were a loss of $0.9 million and a gain of $3.3 million , respectively. In each of these periods, the impact of the gross gains and losses were offset by foreign exchange rate fluctuations on the underlying foreign currency denominated amounts. As of March 26, 2016, the Company did not designate foreign currency exchange forward contracts as hedges for accounting purposes and accordingly, changes in the fair value are recorded in other gain (loss), net, in the accompanying condensed consolidated statements of operations. These contracts were with two high-quality institutions and the Company consistently monitors the creditworthiness of the counterparties. The fair value of derivative instruments in the Company’s condensed consolidated balance sheets was as follows (in thousands): As of March 26, 2016 As of December 26, 2015 Gross Notional (1) Prepaid Expense and Other Assets Other Accrued Liabilities Gross Notional (1) Prepaid Expense and Other Assets Other Accrued Liabilities Foreign currency exchange forward contracts Related to euro denominated receivables $ 26,277 $ 34 $ (16 ) $ 46,753 $ 319 $ (44 ) Related to British pound denominated receivables $ 6,818 291 — $ 6,686 171 — Related to restricted cash $ 256 — — $ 252 — — $ 325 $ (16 ) $ 490 $ (44 ) (1) Represents the face amounts of forward contracts that were outstanding as of the period noted.

Business Combination

Business Combination	3 Months Ended
	Mar. 26, 2016
Business Combinations [Abstract]
Business Combination	Business Combination On August 20, 2015 (the "Acquisition Date”), the Company completed its public offer to the shareholders of Transmode, acquiring 95.8% of the outstanding common shares and voting interest in Transmode. Transmode is a metro packet-optical networking company based in Stockholm, Sweden. The combination of the two companies brings together a complementary set of customers, products, and technologies into one company. With the acquisition of Transmode, Infinera now offers an end-to-end product portfolio of packet-optical solutions for metro, data center interconnect, long-haul and subsea networks. Shortly after the Acquisition Date, the Company initiated compulsory acquisition proceedings in accordance with Swedish law (the "Squeeze-out Proceedings") in order to acquire the remaining 4.2% or 1.2 million Transmode shares not tendered through the end of the offer period. As of the Acquisition Date, the fair value of the noncontrolling interest was approximately $15.4 million , which was based on the implied enterprise value of Transmode at the Acquisition Date. The Squeeze-out Proceedings are expected to be completed during 2016. The Company has accounted for this transaction as a business combination in exchange for total consideration of approximately $350.6 million , which consisted of the following (in thousands, except shares): Cash $ 181,133 Common stock (7,873,055 shares) 169,507 Total $ 350,640 The fair value of the 7.9 million shares of common stock issued was determined based on the closing market price of the Company’s common stock on the Acquisition Date. The Company allocated the fair value of the purchase price of the acquisition to the tangible and intangible assets acquired as well as liabilities assumed, based on their estimated fair values. The excess of the purchase price over the fair values of these identifiable assets and liabilities was recorded as goodwill. The Company prepared an initial determination of the fair value of assets acquired and liabilities assumed as of the acquisition date using preliminary information. In accordance with Accounting Standard Codification 805, "Business Combinations," during the measurement period an acquirer shall retrospectively adjust the provisional amounts recognized at the acquisition date to reflect information obtained about facts and circumstances that existed as of the Acquisition Date that, if known, would have affected the measurement of the amounts recognized as of the Acquisition Date. Accordingly, the Company has recognized measurement period adjustments made during the first quarter of 2016 to the fair value of certain assets acquired and liabilities assumed as a result of additional information obtained. These adjustments were retrospectively applied to the Acquisition Date balance sheet. None of the adjustments had an impact on the Company’s previously reported results of operations. The following table summarizes the Company’s preliminary allocation of the purchase consideration based on the fair value of assets acquired and liabilities assumed as of the Acquisition Date (in thousands): Amounts Recognized as of Acquisition Date Measurement Period Adjustments Total Cash $ 36,688 $ — $ 36,688 Accounts receivable 16,183 — 16,183 Inventory 19,886 — 19,886 Other assets 8,320 — 8,320 Intangible assets, net 161,845 — 161,845 Goodwill 187,220 669 187,889 Current liabilities (24,320 ) (800 ) (25,120 ) Deferred tax liabilities (39,221 ) 131 (39,090 ) Long-term liabilities (589 ) — (589 ) Noncontrolling interest (15,372 ) — (15,372 ) Total net assets $ 350,640 $ — $ 350,640 The Company expects to finalize the allocation of the purchase consideration as soon as practicable, pending finalization of income taxes and any other adjustments related to acquired assets or liabilities, but no later than 12 months from the Acquisition Date. The following table presents details of the identified intangible assets acquired at the Acquisition Date (in thousands): Fair Value Estimated Useful Life (Years) Trade name $ 234 0.5 Customer relationships 49,033 8 Developed technology 92,450 5 In-process technology 20,128 N/A Total $ 161,845 Goodwill generated from this business combination is primarily attributable to the synergies from combining the operations of Transmode with that of the Company, which resulted in expanded selling opportunities of both metro and long-haul solutions. The goodwill recognized is not tax deductible for Swedish income tax purposes. Noncontrolling interest were as follows (in thousands): Three Months Ended March 26, 2016 December 26, 2015 Beginning noncontrolling interest $ 14,910 $ — Noncontrolling interest investment — 15,373 Loss attributable to noncontrolling interest (207 ) (463 ) Ending noncontrolling interest $ 14,703 $ 14,910

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 26, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill Goodwill is recorded when the purchase price of an acquisition exceeds the fair value of the net tangible and identified intangible assets acquired. The following table presents details of the Company’s goodwill during the three months ended March 26, 2016 (in thousands): Balance as of December 26, 2015 $ 191,560 Foreign currency translation adjustments 1,938 Accumulated impairment loss — Balance as of March 26, 2016 $ 193,498 The gross carrying amount of goodwill may change due to the effects of foreign currency fluctuations as a result of acquiring an international business. Additional information existing as of the Acquisition Date but unknown to the Company may become known during the remainder of the measurement period, not to exceed 12 months from the Acquisition Date, which may result in changes to the amounts and allocations recorded. Intangible Assets The following tables present details of the Company’s intangible assets as of March 26, 2016 and December 26, 2015 (in thousands): March 26, 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Remaining Useful Life (In Years) Intangible assets with finite lives: Trade names $ 241 $ (241 ) $ — — Customer relationships 50,497 (3,798 ) 46,699 7.4 Developed technology 99,066 (11,620 ) 87,446 4.5 Other intangible assets 819 (526 ) 293 5.4 Total intangible assets with finite lives $ 150,623 $ (16,185 ) $ 134,438 5.5 In-process technology 16,873 — 16,873 Total intangible assets $ 167,496 $ (16,185 ) $ 151,311 December 26, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Remaining Useful Life (In Years) Intangible assets with finite lives: Trade names $ 239 $ (168 ) $ 71 0.2 Customer relationships 49,991 (2,197 ) 47,794 7.7 Developed technology 94,256 (6,629 ) 87,627 4.6 Other intangible assets 819 (513 ) 306 5.6 Total intangible assets with finite lives $ 145,305 $ (9,507 ) $ 135,798 5.7 In-process technology 20,521 — 20,521 Total intangible assets $ 165,826 $ (9,507 ) $ 156,319 The gross carrying amount of intangible assets and the related amortization expense of intangible assets may change due to the effects of foreign currency fluctuations as a result of acquiring an international business. Amortization expense was $6.5 million for the three months ended March 26, 2016 and was not significant for the three months ended March 28, 2015. Intangible assets are carried at cost less accumulated amortization. Amortization expenses are recorded to the appropriate cost and expense categories. During the three months ended March 26, 2016, the Company transferred $3.9 million of its in-process technology, acquired from Transmode during the third quarter of 2015, to developed technology, which is being amortized over a maximum useful life of 10 years. In-process technology of $16.9 million has not reached technological feasibility as of March 26, 2016 and is not subject to amortization. As such, the Company excluded it in the future amortization expense table below. The following table summarizes the Company’s estimated future amortization expense of intangible assets with finite lives as of March 26, 2016 (in thousands): Fiscal Years Total Remainder of 2016 2017 2018 2019 2020 2021 and Thereafter Total future amortization expense $ 134,438 $ 19,547 $ 26,064 $ 26,064 $ 25,999 $ 19,303 $ 17,461

Balance Sheet Details

Balance Sheet Details	3 Months Ended
	Mar. 26, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Details	Balance Sheet Details The following table provides details of selected balance sheet items (in thousands): March 26, 2016 December 26, 2015 Inventory: Raw materials $ 33,085 $ 27,879 Work in process 59,394 52,599 Finished goods 97,265 94,221 Total inventory $ 189,744 $ 174,699 Property, plant and equipment, net: Computer hardware $ 12,062 $ 11,097 Computer software (1) 22,676 22,548 Laboratory and manufacturing equipment 197,561 189,168 Furniture and fixtures 2,018 1,897 Leasehold improvements 41,545 38,946 Construction in progress 30,426 31,060 Subtotal $ 306,288 $ 294,716 Less accumulated depreciation and amortization (190,916 ) (183,855 ) Total property, plant and equipment, net $ 115,372 $ 110,861 Accrued expenses: Loss contingency related to non-cancelable purchase commitments $ 6,160 $ 6,821 Professional and other consulting fees 5,168 5,363 Taxes payable 2,560 3,295 Royalties 4,449 4,290 Other accrued expenses 14,982 13,967 Total accrued expenses $ 33,319 $ 33,736 (1) Included in computer software at March 26, 2016 and December 26, 2015 were $7.9 million and $7.9 million , respectively, related to an enterprise resource planning ("ERP") system that the Company implemented during 2012. The unamortized ERP costs at March 26, 2016 and December 26, 2015 were $3.7 million and $4.0 million , respectively.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 26, 2016
Equity [Abstract]
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Accumulated other comprehensive income includes certain changes in equity that are excluded from net income. The following table sets forth the changes in accumulated other comprehensive income by component for the three months ended March 26, 2016 (in thousands): Unrealized Gain (Loss) on Other Available-for-Sale Securities Foreign Currency Translation Accumulated Tax Effect Total Balance at December 26, 2015 $ (506 ) $ 2,389 $ (760 ) $ 1,123 Net current-period other comprehensive income 383 3,268 — 3,651 Balance at March 26, 2016 $ (123 ) $ 5,657 $ (760 ) $ 4,774

Basic and Diluted Net Income Pe

Basic and Diluted Net Income Per Common Share	3 Months Ended
	Mar. 26, 2016
Earnings Per Share [Abstract]
Basic and Diluted Net Income Per Common Share	Basic and Diluted Net Income Per Common Share Basic net income per common share is computed by dividing net income attributable to Infinera Corporation by the weighted average number of common shares outstanding during the period. Diluted net income attributable to Infinera Corporation per common share is computed using net income attributable to Infinera Corporation and the weighted average number of common shares outstanding plus potentially dilutive common shares outstanding during the period. Potentially dilutive common shares include the assumed exercise of outstanding stock options, assumed release of outstanding restricted stock units ("RSUs") and performance stock units ("PSUs"), and assumed issuance of common stock under the Company’s 2007 Employee Stock Purchase Plan ("ESPP") using the treasury stock method. Potentially dilutive common shares also include the assumed conversion of convertible senior notes from the conversion spread (as discussed in Note 11, "Convertible Senior Notes"). The Company includes the common shares underlying PSUs in the calculation of diluted net income per share only when they become contingently issuable. In net loss periods, these potentially diluted common shares have been excluded from the diluted net loss calculation. The following table sets forth the computation of net income per common share – basic and diluted (in thousands, except per share amounts): Three Months Ended March 26, 2016 March 28, 2015 Numerator: Net income attributable to Infinera Corporation $ 12,015 $ 12,366 Denominator: Basic weighted average common shares outstanding 140,805 127,840 Effect of dilutive securities: Employee equity plans 3,822 6,569 Assumed conversion of convertible senior notes from conversion spread 2,253 2,895 Diluted weighted average common shares outstanding 146,880 137,304 Net income per common share attributable to Infinera Corporation Basic $ 0.09 $ 0.10 Diluted $ 0.08 $ 0.09 During the three months ended March 26, 2016 and March 28, 2015, the Company included the dilutive effects of the Notes in the calculation of diluted net income per common share as the average market price was above the conversion price of the Notes. The dilutive impact of the Notes was based on the difference between the Company's average stock price during the period and the conversion price of the Notes. Upon conversion of the Notes, it is the Company’s intention to pay cash equal to the lesser of the aggregate principal amount or the conversion value of the Notes being converted, therefore, only the conversion spread relating to the Notes would be included in the Company’s diluted earnings per share calculation unless their effect is anti-dilutive. The effects of certain potentially outstanding shares were not included in the calculation of diluted net income per share for the three months ended March 26, 2016 and March 28, 2015 because their effect were anti-dilutive under the treasury stock method or the performance condition of the award had not been met. The following sets forth the potentially dilutive shares excluded from the computation of the diluted net income per share because their effect was anti-dilutive (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Stock options 9 10 RSUs 779 1,505 PSUs 302 292 ESPP shares 581 415 Total 1,671 2,222 In the three months ended March 26, 2016 and March 28, 2015, the Company included the dilutive effects of the Notes in the calculation of diluted net income per common share as the applicable average market price for certain periods were above the conversion price of the Notes.

Convertible Senior Notes

Convertible Senior Notes	3 Months Ended
	Mar. 26, 2016
Debt Disclosure [Abstract]
Convertible Senior Notes	Convertible Senior Notes In May 2013, the Company issued the Notes, which will mature on June 1, 2018, unless earlier purchased by the Company or converted. Interest is payable semi-annually in arrears on June 1 and December 1 of each year, commencing December 1, 2013. The net proceeds to the Company were approximately $144.5 million . The Notes are governed by an indenture dated as of May 30, 2013 (the "Indenture"), between the Company, as issuer, and U.S. Bank National Association, as trustee. The Notes are unsecured and do not contain any financial covenants or any restrictions on the payment of dividends, the incurrence of senior debt or other indebtedness, or the issuance or repurchase of securities by the Company. Upon conversion, it is the Company’s intention to pay cash equal to the lesser of the aggregate principal amount or the conversion value of the Notes as cash, shares of common stock or a combination of cash and shares of common stock, at the Company’s election, for any remaining conversion obligation. The initial conversion rate is 79.4834 shares of common stock per $1,000 principal amount of Notes, subject to anti-dilution adjustments. The initial conversion price is approximately $12.58 per share of common stock. Throughout the term of the Notes, the conversion rate may be adjusted upon the occurrence of certain events, including for any cash dividends. Holders of the Notes will not receive any cash payment representing accrued and unpaid interest upon conversion of a Note. Accrued but unpaid interest will be deemed to be paid in full upon conversion rather than canceled, extinguished or forfeited. Holders may convert their Notes under the following circumstances: • during any fiscal quarter commencing after the fiscal quarter ended on March 28, 2013 (and only during such fiscal quarter) if the last reported sale price of the common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding fiscal quarter is greater than or equal to 130% of the conversion price on each applicable trading day; • during the five business day period after any five consecutive trading day period (the “measurement period”) in which the trading price per $1,000 principal amount of Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such trading day; • upon the occurrence of specified corporate events described under the Indenture, such as a consolidation, merger or binding share exchange; or • at any time on or after December 1, 2017 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their Notes at any time, regardless of the foregoing circumstances. If the Company undergoes a fundamental change as defined in the Indenture governing the Notes, holders may require the Company to repurchase for cash all or any portion of their Notes at a repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. In addition, upon the occurrence of a “make-whole fundamental change” (as defined in the Indenture), the Company may, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its Notes in connection with such make-whole fundamental change. The net carrying amounts of the debt obligation were as follows (in thousands): March 26, 2016 December 26, 2015 Principal $ 150,000 $ 150,000 Unamortized discount (1) (22,287 ) (24,560 ) Unamortized issuance cost (1) (1,918 ) (2,113 ) Net carrying amount $ 125,795 $ 123,327 (1) Unamortized debt conversion discount and issuance costs will be amortized over the remaining life of the Notes, which is approximately two years. As of March 26, 2016 and December 26, 2015, the carrying amount of the equity components of the Notes was as follows (in thousands): Debt discount related to value of conversion option $ 45,000 Debt issuance cost (1,659 ) Total $ 43,341 In accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar debt instrument that does not have an associated convertible feature. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the par value of the Notes. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. The excess of the principal amount of the liability component over its carrying amount ("debt discount") is amortized to interest expense over the term of the Notes. In accounting for the issuance costs of $5.5 million related to the Notes, the Company allocated the total amount incurred to the liability and equity components of the Notes based on their relative values. Issuance costs attributable to the liability component were initially recorded as other non-current assets and will be amortized to interest expense over the term of the Notes. ASU 2015-03 requires an entity to present such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. The Company has adopted ASU 2015-03 during the first quarter of 2016. The December 26, 2015 balance sheet was retrospectively adjusted to reclassify $2.1 million from other non-current assets to a reduction of the Notes payable liability. The issuance costs attributable to the equity component were netted with the equity component in stockholders’ equity. Additionally, the Company initially recorded a deferred tax liability of $17.0 million in connection with the issuance of the Notes, and a corresponding reduction in valuation allowance. The impact of both was recorded to stockholders’ equity. The Company determined that the embedded conversion option in the Notes does not require separate accounting treatment as a derivative instrument because it is both indexed to the Company’s own stock and would be classified in stockholder’s equity if freestanding. The following table sets forth total interest expense recognized related to the Notes (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Contractual interest expense $ 656 $ 656 Amortization of debt issuance costs 196 177 Amortization of debt discount 2,274 2,057 Total interest expense $ 3,126 $ 2,890 The coupon rate is 1.75% . For the three months ended March 26, 2016 and March 28, 2015 , the debt discount and debt issuance costs are amortized, using an annual effective interest rate of 10.23% , to interest expense over the term of the Notes. As of March 26, 2016 , the fair value of the Notes was $204.9 million . The fair value was determined based on the quoted bid price of the Notes in an over-the-counter market on March 25, 2016. The Notes are classified as Level 2 of the fair value hierarchy. During the three months ended March 26, 2016 , the closing price of the Company's common stock did not meet the conversion criteria; therefore, holders of the Notes may not convert their notes during the second quarter of 2016. Should the closing price conditions be met during the 30 consecutive trading days prior to the end of the second quarter of 2016 or a future quarter, the Notes will be convertible at their holders’ option during the immediately following quarter. Based on the closing price of the Company’s common stock of $15.30 on March 25, 2016, the if-converted value of the Notes exceeded their principal amount by approximately $32.4 million .

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 26, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stockholders' Equity	Stockholders’ Equity Stock-based Compensation Plans The Company has stock-based compensation plans pursuant to which the Company has granted stock options, RSUs and PSUs. The Company also has an ESPP for all eligible employees. As of March 26, 2016 , there were a total of 14.6 million shares of common stock available for grant under the Company’s 2007 Equity Incentive Plan ("2007 Plan"). The following tables summarize the Company’s equity award activity and related information (in thousands, except per share data): Number of Stock Options Weighted-Average Exercise Price Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 2,511 $ 7.26 $ 28,288 Stock options granted — $ — Stock options exercised (57 ) $ 5.14 $ 600 Stock options canceled — $ — Outstanding at March 26, 2016 2,454 $ 7.31 $ 19,672 Vested and expected to vest as of March 26, 2016 2,454 $ 19,670 Exercisable at March 26, 2016 2,443 $ 7.30 $ 19,600 Number of Restricted Stock Units Weighted- Average Grant Date Fair Value Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 4,932 $ 12.76 $ 91,285 RSUs granted 604 $ 15.43 RSUs released (279 ) $ 9.75 $ 4,022 RSUs canceled (142 ) $ 12.98 Outstanding at March 26, 2016 5,115 $ 13.23 $ 78,263 Expected to vest at March 26, 2016 4,855 $ 74,278 Number of Performance Stock Units Weighted- Average Grant Date Fair Value Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 731 $ 12.35 $ 13,540 PSUs granted 424 $ 15.29 PSUs performance earned (1) 154 $ 9.43 PSUs released (462 ) $ 9.43 $ 6,650 PSUs canceled (71 ) $ 15.65 Outstanding at March 26, 2016 776 $ 14.51 $ 11,865 Expected to vest at March 26, 2016 744 $ 11,384 (1) Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts. The aggregate intrinsic value of unexercised stock options is calculated as the difference between the closing price of the Company’s common stock of $15.30 at March 24, 2016 (the last trading day of the fiscal quarter) and the exercise prices of the underlying stock options. The aggregate intrinsic value of the stock options that have been exercised is calculated as the difference between the fair market value of the common stock at the date of exercise and the exercise price of the underlying stock options. The aggregate intrinsic value of unreleased RSUs and unreleased PSUs is calculated using the closing price of the Company's common stock of $15.30 at March 24, 2016 (the last trading day of the fiscal quarter). The aggregate intrinsic value of RSUs and PSUs released is calculated using the fair market value of the common stock at the date of release. The following table presents total stock-based compensation cost for instruments granted but not yet amortized, net of estimated forfeitures, of the Company’s equity compensation plans as of March 26, 2016 . These costs are expected to be amortized on a straight-line basis over the following weighted-average periods (in thousands, except for weighted-average period): Unrecognized Compensation Expense, Net Weighted- Average Period (in years) Stock options $ 40 1.8 RSUs $ 42,653 2.4 PSUs $ 7,962 1.8 Employee Stock Options The Company did not grant any stock options during the three months ended March 26, 2016. Amortization of stock-based compensation related to stock options in the three months ended March 26, 2016 and March 28, 2015 was insignificant in both periods. Employee Stock Purchase Plan The fair value of the ESPP shares was estimated at the date of grant using the following assumptions (expense amounts in thousands): Three Months Ended Employee Stock Purchase Plan March 26, 2016 March 28, 2015 Volatility 56% 53% Risk-free interest rate 0.52% 0.13% Expected life 0.5 years 0.5 years Estimated fair value $4.53 $5.15 Total stock-based compensation expense $1,242 $1,051 Restricted Stock Units During the three months ended March 26, 2016 , the Company granted RSUs to employees and members of the Company’s board of directors to receive an aggregate of 0.6 million shares of the Company’s common stock, respectively. All RSUs awarded are subject to each individual's continued service to the Company through each applicable vesting date. The Company accounted for the fair value of the RSUs using the closing market price of the Company’s common stock on the date of grant. Amortization of stock-based compensation related to RSUs in the three months ended March 26, 2016 and March 28, 2015 was approximately $6.1 million and $5.2 million , respectively. Performance Stock Units Pursuant to the 2007 Plan, the Company has granted PSUs to certain of the Company’s executive officers, senior management and employees. All PSUs awarded are subject to each individual's continued service to the Company through each applicable vesting date and if the performance metrics are not met within the time limits specified in the award agreements, the PSUs will be canceled. A number of PSUs granted to the Company’s executive officers and senior management are based on the total shareholder return of the Company's common stock price as compared to the total shareholder return of a designated index over the span of one year , two years and three years . The number of shares to be issued upon vesting of these PSUs range from 0 to 2.0 times the target number of PSUs granted depending on the Company’s performance against the index. The ranges of estimated values of the PSUs granted that are compared to an index, as well as the assumptions used in calculating these values were based on estimates as follows: 2016 2015 2014 2013 Index SPGIIPTR SPGIIPTR SPGIIPTR NASDAQ Telecom Composite Index volatility 18% 18% - 19% 25% 23% Infinera volatility 55% 48% 49% - 50% 55% Risk-free interest rate 0.95% 0.97% - 1.10% 0.66% - 0.71% 0.42% Correlation with index 0.58 0.52 0.60 0.56 Estimated fair value $12.10 - $16.62 $18.08 - $19.29 $6.59 - $7.60 $6.27 - $7.06 In addition, certain other PSUs granted to the Company’s executive officers, senior management and certain employees will only vest upon the achievement of specific financial or operational performance criteria. The following table summarizes by grant year, the Company’s PSU activity for the three months ended March 26, 2016 (in thousands): Total Number of Performance Stock Units 2013 2014 2015 2016 Outstanding at December 26, 2015 731 147 260 324 — PSUs granted 424 — — — 424 PSUs performance earned (1) 154 70 53 31 — PSUs released (462 ) (211 ) (158 ) (93 ) — PSUs canceled (71 ) (6 ) (8 ) (57 ) — Outstanding at March 26, 2016 776 — 147 205 424 (1) Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts. Amortization of stock-based compensation related to PSUs in the three months ended March 26, 2016 and March 28, 2015 was approximately $0.8 million and $0.9 million , respectively. Stock-Based Compensation The following tables summarize the effects of stock-based compensation on the Company’s condensed consolidated balance sheets and statements of operations for the periods presented (in thousands): March 26, 2016 December 26, 2015 Stock-based compensation effects in inventory $ 3,282 $ 3,129 Stock-based compensation effects in deferred inventory cost $ 13 $ 13 Stock-based compensation effects in fixed assets $ 87 $ 93 Three Months Ended March 26, 2016 March 28, 2015 Stock-based compensation effects included in net income before income taxes Cost of revenue $ 673 $ 482 Research and development 2,321 2,578 Sales and marketing 2,235 1,721 General and administration 1,899 1,666 $ 7,128 $ 6,447 Cost of revenue – amortization from balance sheet (1) 859 761 Total stock-based compensation expense $ 7,987 $ 7,208 (1) Stock-based compensation expense deferred to inventory and deferred inventory costs in prior periods and recognized in the current period.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 26, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Provision for income taxes during the three months ended March 26, 2016 was $0.2 million on pre-tax income of $12.0 million . This compares to a tax provision of $0.6 million on a pre-tax income of $13.0 million during the three months ended March 28, 2015. The results for the three months ended March 26, 2016 reflect approximately $7.0 million of purchase accounting amortization and other charges related to the acquisition of Transmode, with a corresponding tax benefit of approximately $1.5 million . Exclusive of this tax benefit, provision for income taxes otherwise increased by approximately $1.1 million in the three months ended March 26, 2016 compared to March 28, 2015, which relates to a higher effective tax rate applied to a higher pre-tax income. The increase in effective tax rate is attributed to higher state income taxes provided in those states where loss carryforwards are now exhausted as well as higher foreign income taxes related to the Transmode operations and increased spending in certain of the Company's cost-plus foreign subsidiaries. In all periods, the tax expense projected in the Company's effective tax rate assumptions primarily represents foreign taxes of the Company's overseas subsidiaries compensated on a cost-plus basis, as well as the operating results of Transmode, inclusive of purchase accounting charges and amortization for the three months ended March 26, 2016. Due to the Company's significant U.S. loss carryforward position and corresponding full valuation allowance, the Company has not been subject to federal or state tax on its U.S. income because of the availability of loss carryforwards, with the exception of some state taxes for which the losses are limited. The release of transfer pricing reserves in the future will have a beneficial impact to tax expense, but the timing of the impact depends on factors such as expiration of the statute of limitations or settlements with tax authorities. No significant releases are expected in the near future based on information available at this time. The Company must assess the likelihood that some portion or all of its deferred tax assets will be recovered from future taxable income within the respective jurisdictions. In the past, the Company established a valuation allowance against its deferred tax assets as it determined that its ability to recover the value of these assets did not meet the “more-likely-than-not” standard. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management judgment is required on an on-going basis to determine whether it needs to maintain the valuation allowance recorded against its net deferred tax assets. At March 26, 2016, the Company has been profitable for eight consecutive quarters beginning with the second quarter of 2014. Despite this trend, the Company must consider other positive and negative evidence, including its forecasts of taxable income over the applicable carryforward periods, its current financial performance, its market environment, and other factors in evaluating the need for a valuation allowance against its net U.S. deferred tax assets. At March 26, 2016, the Company believes that it is more likely than not, that it would not be able to utilize its deferred tax assets in the foreseeable future. Accordingly, the domestic net deferred tax assets continued to be fully reserved with a valuation allowance. To the extent that the Company determines that deferred tax assets are realizable on a more-likely-than-not basis, and adjustment is needed, that adjustment will be recorded in the period that the determination is made and would generally decrease the valuation allowance and record a corresponding benefit to earnings.

Segment Information

Segment Information	3 Months Ended
	Mar. 26, 2016
Segment Reporting [Abstract]
Segment Information	Segment Information Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker, or decision making group, in deciding how to allocate resources and in assessing performance. The Company’s chief operating decision maker is the Company’s Chief Executive Officer ("CEO"). The Company’s CEO reviews financial information presented on a consolidated basis, accompanied by information about revenue by geographic region for purposes of allocating resources and evaluating financial performance. The Company has one business activity. Accordingly, the Company is considered to be in a single reporting segment and operating unit structure. Revenue by geographic region is based on the shipping address of the customer. The following tables set forth revenue and long-lived assets by geographic region (in thousands): Revenue Three Months Ended March 26, 2016 March 28, 2015 Americas: United States $ 174,515 $ 127,003 Other Americas 3,259 7,086 177,774 134,089 Europe, Middle East and Africa 59,876 45,879 Asia Pacific and Japan 7,168 6,894 Total revenue $ 244,818 $ 186,862 Property, plant and equipment, net March 26, 2016 December 26, 2015 United States $ 106,833 $ 102,702 Other Americas 301 173 107,134 102,875 Europe, Middle East and Africa 5,618 5,417 Asia Pacific and Japan 2,620 2,569 Total property, plant and equipment, net $ 115,372 $ 110,861

Guarantees

Guarantees	3 Months Ended
	Mar. 26, 2016
Guarantees [Abstract]
Guarantees	Guarantees Product Warranties The Company warrants that its products will operate substantially in conformity with product specifications. Hardware warranties provide the purchaser with protection in the event that the product does not perform to product specifications. During the warranty period, the purchaser’s sole and exclusive remedy in the event of such defect or failure to perform is limited to the correction of the defect or failure by repair, refurbishment or replacement, at the Company’s sole option and expense. The Company's hardware warranty periods generally range from one to five years from date of acceptance for hardware and the Company's software warranty is 90 days . Upon delivery of the Company's products, the Company provides for the estimated cost to repair or replace products that may be returned under warranty. The hardware warranty accrual is based on actual historical returns and cost of repair experience and the application of those historical rates to the Company's in-warranty installed base. The provision for warranty claims fluctuates depending upon the installed base of products and the failure rates and costs of repair associated with these products under warranty. Furthermore, the Company's costs of repair vary based on repair volume and its ability to repair, rather than replace, defective units. In the event that actual product failure rates and costs to repair differ from the Company's estimates, revisions to the warranty provision are required. In addition, from time to time, specific hardware warranty accruals may be made if unforeseen technical problems arise with specific products. The Company regularly assesses the adequacy of its recorded warranty liabilities and adjusts the amounts as necessary. Activity related to product warranty was as follows (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Beginning balance $ 38,844 $ 27,040 Charges to operations 6,754 5,348 Utilization (4,987 ) (1,818 ) Change in estimate (1) (612 ) (5,031 ) Balance at the end of the period $ 39,999 $ 25,539 (1) The Company records hardware warranty liabilities based on the latest quality and cost information available as of that date. The changes in estimate shown here are due to changes in overall actual failure rates, the mix of new versus used units related to replacement of failed units, and changes in the estimated cost of repair. As the Company's products mature over time, failure rates and repair costs generally decline leading to favorable changes in warranty reserves. Letters of Credit and Bank Guarantees The Company had $5.2 million of standby letters of credit and bank guarantees outstanding as of March 26, 2016 and December 26, 2015. These consisted of $3.1 million related to customer performance guarantees, $1.2 million related to a value added tax and customs' licenses, and $0.9 million related to property leases. The Company had a line of credit for approximately $1.5 million to support the issuance of letters of credit, of which $0.3 million had been issued and outstanding as of March 26, 2016 and December 26, 2015. The Company has pledged approximately $4.8 million of assets of a subsidiary to secure this line of credit and other obligations.

Litigation and Contingencies

Litigation and Contingencies	3 Months Ended
	Mar. 26, 2016
Commitments and Contingencies Disclosure [Abstract]
Litigation and Contingencies	Litigation and Contingencies From time to time, the Company is subject to various legal proceedings, claims and litigation arising in the ordinary course of business. While the outcome of these matters is currently not determinable, the Company does not expect that the ultimate costs to resolve these matters will have a material effect on its consolidated financial position, results of operations or cash flows. The Company is subject to the possibility of various losses arising in the ordinary course of business. These may relate to disputes, litigation and other legal actions. In the preparation of its quarterly and annual financial statements, the Company considers the likelihood of loss or the incurrence of a liability, including whether it is probable, reasonably possible or remote that a liability has been incurred, as well as the Company’s ability to reasonably estimate the amount of loss, in determining loss contingencies. In accordance with U.S. GAAP, an estimated loss contingency is accrued when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. The Company regularly evaluates current information to determine whether any accruals should be adjusted and whether new accruals are required. As of March 26, 2016, the Company has accrued the estimated liabilities associated with the Company's potential loss contingencies.

Basis of Presentation and Sig23

Basis of Presentation and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 26, 2016
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2016, the Financial Accounting Standards Board (the "FASB") issued Accounting Standards Update 2016-11, "Revenue Recognition (Topic 605) and Derivatives and Hedging (Topic 815): Rescission of SEC Guidance Because of Accounting Standards Updates 2014-09 and 2014-16 Pursuant to Staff Announcements at the March 3, 2016 EITF Meeting (SEC Update)") ("ASU 2016-11"), which rescinds various standards codified as part of Topic 605, Revenue Recognition in relation to the future adoption of Topic 606. These rescissions include changes to topics pertaining to revenue and expense recognition for freight Services in process, accounting for shipping and handling fees and costs and accounting for consideration given by a vendor to a customer. This guidance is effective for the Company in its first quarter of fiscal 2018 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-11 will have on its consolidated financial statements. In April 2016, the FASB issued Accounting Standards Update 2016-10, "Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing" ("ASU 2016-10"), to address the potential diversity in practice at initial application and cost; and the complexity of applying Topic 606, both at transition and on an ongoing basis related to identification of performance obligations and licensing arrangements. The new accounting guidance is effective for the Company in its first quarter of fiscal 2018 and early adoption permitted.The Company is currently evaluating the impact of adoption of this update on its consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-09, "Improvements to Employee Share-Based Payment Accounting") ("ASU 2016-09"), which includes provisions intended to simplify various aspects related to how share-based payments are accounted for and presented in the financial statements, including the income tax effects of share-based payments and accounting for forfeitures. This guidance is effective for the Company in its first quarter of fiscal 2017 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-09 will have on its consolidated financial statements. In March 2016, the FASB issued Accounting Standards Update 2016-06, "Derivatives and Hedging (Topic 815): Contingent Put and Call Options in Debt Instruments (a consensus of the Emerging Issues Task Force)" ("ASU 2016-06"), which applies to all entities that are issuers of or investors in debt instruments (or hybrid financial instruments that are determined to have a debt host) with embedded call (put) options, and requires that embedded derivatives be separated from the host contract and accounted for separately as derivatives if certain criteria are met. One criterion is that the economic characteristics and risks of the embedded derivatives are not clearly and closely related to the economic characteristics and risks of the host contract. This guidance is effective for the Company in its first quarter of fiscal 2017 and early adoption is permitted. The Company is currently evaluating the method and impact the adoption of ASU 2016-06 will have on its consolidated financial statements. In February 2016, the FASB issued Accounting Standards Update 2016-02, "Leases (Topic 842)" ("ASU 2016-02"), which amends the existing accounting standards for leases. The new standard requires lessees to record a right-of-use asset and a corresponding lease liability on the balance sheet (with the exception of short-term leases). For lessees, leases will continue to be classified as either operating or financing in the income statement. This guidance is effective for the Company in its first quarter of fiscal 2019 and early adoption is permitted. ASU 2016-02 is required to be applied with a modified retrospective approach and requires application of the new standard at the beginning of the earliest comparative period presented. The Company is currently evaluating the method and impact the adoption of ASU 2016-02 will have on its consolidated financial statements. In September 2015, the FASB issued Accounting Standards Update 2015-16, "Business Combinations and Simplifying the Accounting for Measurement-Period Adjustments" ("ASU 2015-16"), which eliminates the requirement for an acquirer in a business combination to account for measurement-period adjustments retrospectively. Instead, an acquirer will recognize a measurement-period adjustment during the period in which it determines the amount of the adjustment. The guidance is effective for the Company in its first quarter of fiscal 2016. The Company's adoption of ASU 2015-16 had no impact on the Company's financial position, results of operations or cash flow. In July 2015, the FASB issued Accounting Standards Update 2015-11, "Simplifying the Measurement of Inventory" ("ASU 2015-11"), to simplify the guidance on the subsequent measurement of inventory, excluding inventory measured using last-in, first-out or the retail inventory method. Under ASU 2015-11, inventory should be at the lower of cost and net realizable value. The new accounting guidance is effective for the Company in its first quarter of fiscal 2017 with early adoption permitted. The Company is currently evaluating the impact of the pending adoption of ASU 2015-11 on its consolidated financial statements. In April 2015, the FASB issued Accounting Standards Update 2015-03, "Simplifying the Presentation of Debt Issuance Costs" ("ASU 2015-03"), which changes the presentation of debt issuance costs in financial statements. ASU 2015-03 requires an entity to present such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs will continue to be reported as interest expense. The Company has adopted ASU 2015-03 during the first quarter of 2016. The December 26, 2015 balance sheet was retrospectively adjusted to reclassify $2.1 million from other non-current assets to a reduction of the Notes payable liability. In May 2014, the FASB issued Accounting Standards Update 2014-09, "Revenue from Contracts from Customers" ("ASU 2014-09"). ASU 2014-09 provides a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. ASU 2014-09 will require an entity to recognize revenue when it transfers 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. This update creates a five-step model that requires entities to exercise judgment when considering the terms of the contract(s), which include (i) identifying the contract(s) with the customer; (ii) identifying the separate performance obligations in the contract; (iii) determining the transaction price; (iv) allocating the transaction price to the separate performance obligations; and (v) recognizing revenue when each performance obligation is satisfied. In July 2015, the FASB deferred the effective date for annual reporting periods beginning after December 15, 2017 (including interim reporting periods within those periods). Early adoption is permitted to the original effective date of December 15, 2016 (including interim reporting periods within those periods). ASU 2014-09 will be effective for the Company’s first quarter of 2018. The Company has the option to apply the provisions of ASU 2014-09 either retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of applying this standard recognized at the date of initial application. The Company is currently evaluating the method and impact the adoption of ASU 2014-09 will have on its consolidated financial statements.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 26, 2016
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following tables represent the Company’s fair value hierarchy for its assets and liabilities measured at fair value on a recurring basis (in thousands): As of March 26, 2016 As of December 26, 2015 Fair Value Measured Using Fair Value Measured Using Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets Money market funds $ 61,077 $ — $ — $ 61,077 $ 37,829 $ — $ — $ 37,829 Certificates of deposit — 3,565 — 3,565 — 5,001 — 5,001 Commercial paper — 8,980 — 8,980 — 10,997 — 10,997 Corporate bonds — 120,002 — 120,002 — 163,400 — 163,400 U.S. agency notes — 10,761 — 10,761 — 10,717 — 10,717 U.S. treasuries 39,289 — — 39,289 24,851 — — 24,851 Foreign currency exchange forward contracts — 325 — 325 — 490 — 490 Total assets $ 100,366 $ 143,633 $ — $ 243,999 $ 62,680 $ 190,605 $ — $ 253,285 Liabilities Foreign currency exchange forward contracts $ — $ (16 ) $ — $ (16 ) $ — $ (44 ) $ — $ (44 )
Investments at Fair Value	Investments at fair value were as follows (in thousands): March 26, 2016 Adjusted Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Money market funds $ 61,077 $ — $ — $ 61,077 Certificates of deposit 3,560 5 — 3,565 Commercial paper 8,985 — (5 ) 8,980 Corporate bonds 120,097 23 (118 ) 120,002 U.S. agency notes 10,786 — (25 ) 10,761 U.S. treasuries 39,293 12 (16 ) 39,289 Total available-for-sale investments $ 243,798 $ 40 $ (164 ) $ 243,674 December 26, 2015 Adjusted Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value Money market funds $ 37,829 $ — $ — $ 37,829 Certificates of deposit 5,000 1 — 5,001 Commercial paper 10,997 — — 10,997 Corporate bonds 163,797 — (397 ) 163,400 U.S. agency notes 10,786 — (69 ) 10,717 U.S. treasuries 24,894 — (43 ) 24,851 Total available-for-sale investments $ 253,303 $ 1 $ (509 ) $ 252,795

Derivative Instruments (Tables)

Derivative Instruments (Tables)	3 Months Ended
	Mar. 26, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair Value of Derivative Instruments not Designated as Hedging Instruments	The fair value of derivative instruments in the Company’s condensed consolidated balance sheets was as follows (in thousands): As of March 26, 2016 As of December 26, 2015 Gross Notional (1) Prepaid Expense and Other Assets Other Accrued Liabilities Gross Notional (1) Prepaid Expense and Other Assets Other Accrued Liabilities Foreign currency exchange forward contracts Related to euro denominated receivables $ 26,277 $ 34 $ (16 ) $ 46,753 $ 319 $ (44 ) Related to British pound denominated receivables $ 6,818 291 — $ 6,686 171 — Related to restricted cash $ 256 — — $ 252 — — $ 325 $ (16 ) $ 490 $ (44 ) (1) Represents the face amounts of forward contracts that were outstanding as of the period noted.

Business Combination (Tables)

Business Combination (Tables)	3 Months Ended
	Mar. 26, 2016
Business Combinations [Abstract]
Schedule of Business Acquisitions by Acquisition, Equity Interest Issued or Issuable	The Company has accounted for this transaction as a business combination in exchange for total consideration of approximately $350.6 million , which consisted of the following (in thousands, except shares): Cash $ 181,133 Common stock (7,873,055 shares) 169,507 Total $ 350,640
Schedule of Business Acquisitions, by Acquisition	The following table summarizes the Company’s preliminary allocation of the purchase consideration based on the fair value of assets acquired and liabilities assumed as of the Acquisition Date (in thousands): Amounts Recognized as of Acquisition Date Measurement Period Adjustments Total Cash $ 36,688 $ — $ 36,688 Accounts receivable 16,183 — 16,183 Inventory 19,886 — 19,886 Other assets 8,320 — 8,320 Intangible assets, net 161,845 — 161,845 Goodwill 187,220 669 187,889 Current liabilities (24,320 ) (800 ) (25,120 ) Deferred tax liabilities (39,221 ) 131 (39,090 ) Long-term liabilities (589 ) — (589 ) Noncontrolling interest (15,372 ) — (15,372 ) Total net assets $ 350,640 $ — $ 350,640
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination	The following table presents details of the identified intangible assets acquired at the Acquisition Date (in thousands): Fair Value Estimated Useful Life (Years) Trade name $ 234 0.5 Customer relationships 49,033 8 Developed technology 92,450 5 In-process technology 20,128 N/A Total $ 161,845
Schedule of Indefinite-lived Intangible Assets Acquired as Part of Business Combination	The following table presents details of the identified intangible assets acquired at the Acquisition Date (in thousands): Fair Value Estimated Useful Life (Years) Trade name $ 234 0.5 Customer relationships 49,033 8 Developed technology 92,450 5 In-process technology 20,128 N/A Total $ 161,845
Noncontrolling Interest Rollfoward	Noncontrolling interest were as follows (in thousands): Three Months Ended March 26, 2016 December 26, 2015 Beginning noncontrolling interest $ 14,910 $ — Noncontrolling interest investment — 15,373 Loss attributable to noncontrolling interest (207 ) (463 ) Ending noncontrolling interest $ 14,703 $ 14,910

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 26, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table presents details of the Company’s goodwill during the three months ended March 26, 2016 (in thousands): Balance as of December 26, 2015 $ 191,560 Foreign currency translation adjustments 1,938 Accumulated impairment loss — Balance as of March 26, 2016 $ 193,498
Schedule of Finite-Lived Intangible Assets	The following tables present details of the Company’s intangible assets as of March 26, 2016 and December 26, 2015 (in thousands): March 26, 2016 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Remaining Useful Life (In Years) Intangible assets with finite lives: Trade names $ 241 $ (241 ) $ — — Customer relationships 50,497 (3,798 ) 46,699 7.4 Developed technology 99,066 (11,620 ) 87,446 4.5 Other intangible assets 819 (526 ) 293 5.4 Total intangible assets with finite lives $ 150,623 $ (16,185 ) $ 134,438 5.5 In-process technology 16,873 — 16,873 Total intangible assets $ 167,496 $ (16,185 ) $ 151,311 December 26, 2015 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Remaining Useful Life (In Years) Intangible assets with finite lives: Trade names $ 239 $ (168 ) $ 71 0.2 Customer relationships 49,991 (2,197 ) 47,794 7.7 Developed technology 94,256 (6,629 ) 87,627 4.6 Other intangible assets 819 (513 ) 306 5.6 Total intangible assets with finite lives $ 145,305 $ (9,507 ) $ 135,798 5.7 In-process technology 20,521 — 20,521 Total intangible assets $ 165,826 $ (9,507 ) $ 156,319
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table summarizes the Company’s estimated future amortization expense of intangible assets with finite lives as of March 26, 2016 (in thousands): Fiscal Years Total Remainder of 2016 2017 2018 2019 2020 2021 and Thereafter Total future amortization expense $ 134,438 $ 19,547 $ 26,064 $ 26,064 $ 25,999 $ 19,303 $ 17,461

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	3 Months Ended
	Mar. 26, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Details of Selected Balance Sheet Items	The following table provides details of selected balance sheet items (in thousands): March 26, 2016 December 26, 2015 Inventory: Raw materials $ 33,085 $ 27,879 Work in process 59,394 52,599 Finished goods 97,265 94,221 Total inventory $ 189,744 $ 174,699 Property, plant and equipment, net: Computer hardware $ 12,062 $ 11,097 Computer software (1) 22,676 22,548 Laboratory and manufacturing equipment 197,561 189,168 Furniture and fixtures 2,018 1,897 Leasehold improvements 41,545 38,946 Construction in progress 30,426 31,060 Subtotal $ 306,288 $ 294,716 Less accumulated depreciation and amortization (190,916 ) (183,855 ) Total property, plant and equipment, net $ 115,372 $ 110,861 Accrued expenses: Loss contingency related to non-cancelable purchase commitments $ 6,160 $ 6,821 Professional and other consulting fees 5,168 5,363 Taxes payable 2,560 3,295 Royalties 4,449 4,290 Other accrued expenses 14,982 13,967 Total accrued expenses $ 33,319 $ 33,736 (1) Included in computer software at March 26, 2016 and December 26, 2015 were $7.9 million and $7.9 million , respectively, related to an enterprise resource planning ("ERP") system that the Company implemented during 2012. The unamortized ERP costs at March 26, 2016 and December 26, 2015 were $3.7 million and $4.0 million , respectively

Accumulated Other Comprehensi29

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 26, 2016
Equity [Abstract]
Summary of Changes in Accumulated Other Comprehensive Income (Loss)	The following table sets forth the changes in accumulated other comprehensive income by component for the three months ended March 26, 2016 (in thousands): Unrealized Gain (Loss) on Other Available-for-Sale Securities Foreign Currency Translation Accumulated Tax Effect Total Balance at December 26, 2015 $ (506 ) $ 2,389 $ (760 ) $ 1,123 Net current-period other comprehensive income 383 3,268 — 3,651 Balance at March 26, 2016 $ (123 ) $ 5,657 $ (760 ) $ 4,774

Basic and Diluted Net Income 30

Basic and Diluted Net Income Per Common Share (Tables)	3 Months Ended
	Mar. 26, 2016
Earnings Per Share [Abstract]
Computation of Net Income (Loss) Per Common Share Basic and Diluted	The following table sets forth the computation of net income per common share – basic and diluted (in thousands, except per share amounts): Three Months Ended March 26, 2016 March 28, 2015 Numerator: Net income attributable to Infinera Corporation $ 12,015 $ 12,366 Denominator: Basic weighted average common shares outstanding 140,805 127,840 Effect of dilutive securities: Employee equity plans 3,822 6,569 Assumed conversion of convertible senior notes from conversion spread 2,253 2,895 Diluted weighted average common shares outstanding 146,880 137,304 Net income per common share attributable to Infinera Corporation Basic $ 0.09 $ 0.10 Diluted $ 0.08 $ 0.09
Antidilutive Shares Excluded from Computation of Diluted Net Income (Loss) Per Share	The following sets forth the potentially dilutive shares excluded from the computation of the diluted net income per share because their effect was anti-dilutive (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Stock options 9 10 RSUs 779 1,505 PSUs 302 292 ESPP shares 581 415 Total 1,671 2,222

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	3 Months Ended
	Mar. 26, 2016
Debt Disclosure [Abstract]
Components of Convertible Senior Notes	The net carrying amounts of the debt obligation were as follows (in thousands): March 26, 2016 December 26, 2015 Principal $ 150,000 $ 150,000 Unamortized discount (1) (22,287 ) (24,560 ) Unamortized issuance cost (1) (1,918 ) (2,113 ) Net carrying amount $ 125,795 $ 123,327 (1) Unamortized debt conversion discount and issuance costs will be amortized over the remaining life of the Notes, which is approximately two years.
Schedule of Long-term Debt Instruments	As of March 26, 2016 and December 26, 2015, the carrying amount of the equity components of the Notes was as follows (in thousands): Debt discount related to value of conversion option $ 45,000 Debt issuance cost (1,659 ) Total $ 43,341
Interest expense recognized related to Notes	The following table sets forth total interest expense recognized related to the Notes (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Contractual interest expense $ 656 $ 656 Amortization of debt issuance costs 196 177 Amortization of debt discount 2,274 2,057 Total interest expense $ 3,126 $ 2,890

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 26, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Company's Equity Award Activity - Options	The following tables summarize the Company’s equity award activity and related information (in thousands, except per share data): Number of Stock Options Weighted-Average Exercise Price Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 2,511 $ 7.26 $ 28,288 Stock options granted — $ — Stock options exercised (57 ) $ 5.14 $ 600 Stock options canceled — $ — Outstanding at March 26, 2016 2,454 $ 7.31 $ 19,672 Vested and expected to vest as of March 26, 2016 2,454 $ 19,670 Exercisable at March 26, 2016 2,443 $ 7.30 $ 19,600
Summary of Company's Equity Award Activity - RSUs	Number of Restricted Stock Units Weighted- Average Grant Date Fair Value Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 4,932 $ 12.76 $ 91,285 RSUs granted 604 $ 15.43 RSUs released (279 ) $ 9.75 $ 4,022 RSUs canceled (142 ) $ 12.98 Outstanding at March 26, 2016 5,115 $ 13.23 $ 78,263 Expected to vest at March 26, 2016 4,855 $ 74,278
Summary of Company's Equity Award Activity - PSUs	Number of Performance Stock Units Weighted- Average Grant Date Fair Value Per Share Aggregate Intrinsic Value Outstanding at December 26, 2015 731 $ 12.35 $ 13,540 PSUs granted 424 $ 15.29 PSUs performance earned (1) 154 $ 9.43 PSUs released (462 ) $ 9.43 $ 6,650 PSUs canceled (71 ) $ 15.65 Outstanding at March 26, 2016 776 $ 14.51 $ 11,865 Expected to vest at March 26, 2016 744 $ 11,384 (1) Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts.
Total Stock Based Compensation Cost for Instruments Granted but Not Yet Amortized	The following table presents total stock-based compensation cost for instruments granted but not yet amortized, net of estimated forfeitures, of the Company’s equity compensation plans as of March 26, 2016 . These costs are expected to be amortized on a straight-line basis over the following weighted-average periods (in thousands, except for weighted-average period): Unrecognized Compensation Expense, Net Weighted- Average Period (in years) Stock options $ 40 1.8 RSUs $ 42,653 2.4 PSUs $ 7,962 1.8
Estimated Fair Value of ESPP Shares	The fair value of the ESPP shares was estimated at the date of grant using the following assumptions (expense amounts in thousands): Three Months Ended Employee Stock Purchase Plan March 26, 2016 March 28, 2015 Volatility 56% 53% Risk-free interest rate 0.52% 0.13% Expected life 0.5 years 0.5 years Estimated fair value $4.53 $5.15 Total stock-based compensation expense $1,242 $1,051
Schedule of Share-based Payment Award, Valuation Assumptions	The ranges of estimated values of the PSUs granted that are compared to an index, as well as the assumptions used in calculating these values were based on estimates as follows: 2016 2015 2014 2013 Index SPGIIPTR SPGIIPTR SPGIIPTR NASDAQ Telecom Composite Index volatility 18% 18% - 19% 25% 23% Infinera volatility 55% 48% 49% - 50% 55% Risk-free interest rate 0.95% 0.97% - 1.10% 0.66% - 0.71% 0.42% Correlation with index 0.58 0.52 0.60 0.56 Estimated fair value $12.10 - $16.62 $18.08 - $19.29 $6.59 - $7.60 $6.27 - $7.06
Schedule Of Nonvested Performance Based Units Activity By Grant Year	The following table summarizes by grant year, the Company’s PSU activity for the three months ended March 26, 2016 (in thousands): Total Number of Performance Stock Units 2013 2014 2015 2016 Outstanding at December 26, 2015 731 147 260 324 — PSUs granted 424 — — — 424 PSUs performance earned (1) 154 70 53 31 — PSUs released (462 ) (211 ) (158 ) (93 ) — PSUs canceled (71 ) (6 ) (8 ) (57 ) — Outstanding at March 26, 2016 776 — 147 205 424 (1) Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts.
Summary of Effects of Stock-Based Compensation on Company's Balance Sheets and Statements of Operations	The following tables summarize the effects of stock-based compensation on the Company’s condensed consolidated balance sheets and statements of operations for the periods presented (in thousands): March 26, 2016 December 26, 2015 Stock-based compensation effects in inventory $ 3,282 $ 3,129 Stock-based compensation effects in deferred inventory cost $ 13 $ 13 Stock-based compensation effects in fixed assets $ 87 $ 93 Three Months Ended March 26, 2016 March 28, 2015 Stock-based compensation effects included in net income before income taxes Cost of revenue $ 673 $ 482 Research and development 2,321 2,578 Sales and marketing 2,235 1,721 General and administration 1,899 1,666 $ 7,128 $ 6,447 Cost of revenue – amortization from balance sheet (1) 859 761 Total stock-based compensation expense $ 7,987 $ 7,208 (1) Stock-based compensation expense deferred to inventory and deferred inventory costs in prior periods and recognized in the current period.

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 26, 2016
Segment Reporting [Abstract]
Revenue and Long-Lived Assets by Geographic Region	Revenue by geographic region is based on the shipping address of the customer. The following tables set forth revenue and long-lived assets by geographic region (in thousands): Revenue Three Months Ended March 26, 2016 March 28, 2015 Americas: United States $ 174,515 $ 127,003 Other Americas 3,259 7,086 177,774 134,089 Europe, Middle East and Africa 59,876 45,879 Asia Pacific and Japan 7,168 6,894 Total revenue $ 244,818 $ 186,862
Property, Plant and Equipment, Net	Property, plant and equipment, net March 26, 2016 December 26, 2015 United States $ 106,833 $ 102,702 Other Americas 301 173 107,134 102,875 Europe, Middle East and Africa 5,618 5,417 Asia Pacific and Japan 2,620 2,569 Total property, plant and equipment, net $ 115,372 $ 110,861

Guarantees (Tables)

Guarantees (Tables)	3 Months Ended
	Mar. 26, 2016
Guarantees [Abstract]
Activity Related to Product Warranty	Activity related to product warranty was as follows (in thousands): Three Months Ended March 26, 2016 March 28, 2015 Beginning balance $ 38,844 $ 27,040 Charges to operations 6,754 5,348 Utilization (4,987 ) (1,818 ) Change in estimate (1) (612 ) (5,031 ) Balance at the end of the period $ 39,999 $ 25,539 (1) The Company records hardware warranty liabilities based on the latest quality and cost information available as of that date. The changes in estimate shown here are due to changes in overall actual failure rates, the mix of new versus used units related to replacement of failed units, and changes in the estimated cost of repair. As the Company's products mature over time, failure rates and repair costs generally decline leading to favorable changes in warranty reserves.

Basis of Presentation and Sig35

Basis of Presentation and Significant Accounting Polices (Details)	3 Months Ended
	Mar. 26, 2016customer	Mar. 28, 2015customer	May. 30, 2013USD ($)
Concentration Risk [Line Items]
Customers accounting for a significant portion of revenue | customer	3	2
Sales Revenue, Net | Customer One | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk	17.00%	18.00%
Sales Revenue, Net | Customer Two | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk	16.00%	16.00%
Sales Revenue, Net | Customer Three | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk	14.00%
1.75% Convertible Senior Notes Due June 1, 2018
Concentration Risk [Line Items]
Principal amount | $			$ 150,000,000
Debt instrument interest percentage	1.75%	1.75%	1.75%

Recent Accounting Pronounceme36

Recent Accounting Pronouncements (Details) - Accounting Standards Update 2015-03 $ in Millions	Dec. 26, 2015USD ($)
Other Noncurrent Assets
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Debt issuance costs	$ (2.1)
Long-term Debt
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Debt issuance costs	$ 2.1

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Assets
Total Assets	$ 243,999	$ 253,285
Foreign currency exchange forward contracts
Assets
Total Assets	325	490
Liabilities
Total Liabilities	(16)	(44)
Money market funds
Assets
Total Assets	61,077	37,829
Certificates of deposit
Assets
Total Assets	3,565	5,001
Commercial paper
Assets
Total Assets	8,980	10,997
Corporate bonds
Assets
Total Assets	120,002	163,400
U.S. agency notes
Assets
Total Assets	10,761	10,717
U.S. treasuries
Assets
Total Assets	39,289	24,851
Level 1
Assets
Total Assets	100,366	62,680
Level 1 | Foreign currency exchange forward contracts
Assets
Total Assets	0	0
Liabilities
Total Liabilities	0	0
Level 1 | Money market funds
Assets
Total Assets	61,077	37,829
Level 1 | Certificates of deposit
Assets
Total Assets	0	0
Level 1 | Commercial paper
Assets
Total Assets	0	0
Level 1 | Corporate bonds
Assets
Total Assets	0	0
Level 1 | U.S. agency notes
Assets
Total Assets	0	0
Level 1 | U.S. treasuries
Assets
Total Assets	39,289	24,851
Level 2
Assets
Total Assets	143,633	190,605
Level 2 | Foreign currency exchange forward contracts
Assets
Total Assets	325	490
Liabilities
Total Liabilities	(16)	(44)
Level 2 | Money market funds
Assets
Total Assets	0	0
Level 2 | Certificates of deposit
Assets
Total Assets	3,565	5,001
Level 2 | Commercial paper
Assets
Total Assets	8,980	10,997
Level 2 | Corporate bonds
Assets
Total Assets	120,002	163,400
Level 2 | U.S. agency notes
Assets
Total Assets	10,761	10,717
Level 2 | U.S. treasuries
Assets
Total Assets	0	0
Level 3
Assets
Total Assets	0	0
Level 3 | Foreign currency exchange forward contracts
Assets
Total Assets	0	0
Liabilities
Total Liabilities	0	0
Level 3 | Money market funds
Assets
Total Assets	0	0
Level 3 | Certificates of deposit
Assets
Total Assets	0	0
Level 3 | Commercial paper
Assets
Total Assets	0	0
Level 3 | Corporate bonds
Assets
Total Assets	0	0
Level 3 | U.S. agency notes
Assets
Total Assets	0	0
Level 3 | U.S. treasuries
Assets
Total Assets	$ 0	$ 0

Fair Value Measurements - Inves

Fair Value Measurements - Investments at Fair Value (Details) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	$ 243,798	$ 253,303
Gross Unrealized Gains	40	1
Gross Unrealized Losses	(164)	(509)
Fair Value	243,674	252,795
Money market funds
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	61,077	37,829
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	61,077	37,829
Certificates of deposit
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	3,560	5,000
Gross Unrealized Gains	5	1
Gross Unrealized Losses	0	0
Fair Value	3,565	5,001
Commercial paper
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	8,985	10,997
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(5)	0
Fair Value	8,980	10,997
Corporate bonds
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	120,097	163,797
Gross Unrealized Gains	23	0
Gross Unrealized Losses	(118)	(397)
Fair Value	120,002	163,400
U.S. agency notes
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	10,786	10,786
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(25)	(69)
Fair Value	10,761	10,717
U.S. treasuries
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Adjusted Amortized Cost	39,293	24,894
Gross Unrealized Gains	12	0
Gross Unrealized Losses	(16)	(43)
Fair Value	$ 39,289	$ 24,851

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 26, 2016	Dec. 26, 2015
Fair Value Disclosures [Abstract]
Available-for-sale investments	22 months
Cash	$ 111.9	$ 98.4

Cost-method Investment - Additi

Cost-method Investment - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 26, 2016	Dec. 26, 2015
Investments, All Other Investments [Abstract]
Cost-method investment	$ 14,500,000	$ 14,500,000
Less than percent of voting securities	20.00%
Impairment charge on cost-method investments	$ 0

Derivative Instruments - Additi

Derivative Instruments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Before-tax effect of foreign currency exchange forward contracts not designated as hedging instruments, gain (loss)	$ (0.9)	$ 3.3
Foreign currency exchange forward contracts, maturities	1 year

Derivative Instruments - Fair V

Derivative Instruments - Fair Value of Derivative Instruments Not Designated as Hedging Activities (Details) - USD ($)		Mar. 26, 2016	Dec. 26, 2015
Derivative [Line Items]
Prepaid expenses and other current assets		$ 29,689,000	$ 29,511,000
Not Designated as Hedging Instrument
Derivative [Line Items]
Prepaid expenses and other current assets		325,000	490,000
Other Accrued Liabilities		(16,000)	(44,000)
Not Designated as Hedging Instrument | Related to euro denominated receivables
Derivative [Line Items]
Forward contract notional amount	[1]	26,277,000	46,753,000
Prepaid expenses and other current assets		34,000	319,000
Other Accrued Liabilities		(16,000)	(44,000)
Not Designated as Hedging Instrument | Related to British pound denominated receivables
Derivative [Line Items]
Forward contract notional amount	[1]	6,818,000	6,686,000
Prepaid expenses and other current assets		291,000	171,000
Other Accrued Liabilities		0	0
Not Designated as Hedging Instrument | Related to restricted cash
Derivative [Line Items]
Forward contract notional amount	[1]	256,000	252,000
Prepaid expenses and other current assets		0	0
Other Accrued Liabilities		$ 0	$ 0
[1]	Represents the face amounts of forward contracts that were outstanding as of the period noted.

Business Combination (Details)

Business Combination (Details) - USD ($) $ in Thousands, shares in Millions	Aug. 20, 2015	Dec. 31, 2016	Mar. 26, 2016	Dec. 26, 2015	Dec. 27, 2014
Business Acquisition [Line Items]
Noncontrolling interest			$ 14,703	$ 14,910	$ 0
Transmode
Business Acquisition [Line Items]
Percentage of acquiree common shares acquired	95.80%
Noncontrolling interest	$ 15,372
Total consideration transfered	$ 350,640
Scenario, Forecast | Transmode
Business Acquisition [Line Items]
Percentage of acquiree common shares acquired		4.20%
Remaining acquiree shares (in shares)		1.2

Business Combination Total Cons

Business Combination Total Consideration For Acquisition (Details) - Transmode $ in Thousands	Aug. 20, 2015USD ($)shares
Business Acquisition [Line Items]
Cash	$ 181,133
Common stock (7,873,055 shares)	169,507
Total	$ 350,640
Common shares issued in acquisition (in shares) | shares	7,873,055

Business Combination Allocation

Business Combination Allocation Of Purchase Consideration (Details) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015	Aug. 20, 2015	Dec. 27, 2014
Business Acquisition [Line Items]
Goodwill	$ 193,498	$ 191,560
Noncontrolling interest	$ (14,703)	$ (14,910)		$ 0
Transmode
Business Acquisition [Line Items]
Cash			$ 36,688
Accounts receivable			16,183
Inventory			19,886
Other assets			8,320
Intangible assets, net			161,845
Goodwill			187,889
Current liabilities			(25,120)
Deferred tax liabilities			(39,090)
Long-term liabilities			(589)
Noncontrolling interest			(15,372)
Total net assets			350,640
Scenario, Previously Reported | Transmode
Business Acquisition [Line Items]
Cash			36,688
Accounts receivable			16,183
Inventory			19,886
Other assets			8,320
Intangible assets, net			161,845
Goodwill			187,220
Current liabilities			(24,320)
Deferred tax liabilities			(39,221)
Long-term liabilities			(589)
Noncontrolling interest			(15,372)
Total net assets			350,640
Scenario, Adjustment | Transmode
Business Acquisition [Line Items]
Cash			0
Accounts receivable			0
Inventory			0
Other assets			0
Intangible assets, net			0
Goodwill			669
Current liabilities			(800)
Deferred tax liabilities			131
Long-term liabilities			0
Noncontrolling interest			0
Total net assets			$ 0

Business Combination Intangible

Business Combination Intangible Assets Acquired (Details) - USD ($) $ in Thousands	Aug. 20, 2015	Mar. 26, 2016	Dec. 26, 2015
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets gross		$ 167,496	$ 165,826
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		5 years 6 months	5 years 8 months 16 days
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		0 days	1 month 24 days
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years 4 months 24 days	7 years 7 months 24 days
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		4 years 6 months	4 years 7 months 24 days
Transmode
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets gross	$ 161,845
Transmode | Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets acquired	$ 234
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	6 months
Transmode | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets acquired	$ 49,033
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	8 years
Transmode | Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite lived intangible assets acquired	$ 92,450
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Transmode | In-process technology
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets acquired	$ 20,128

Business Combination Business C

Business Combination Business Combination Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 26, 2016	Mar. 28, 2015	Dec. 26, 2015
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning noncontrolling interest	$ 14,910	$ 0	$ 0
Less: Loss attributable to noncontrolling interest	(207)	$ 0	(463)
Ending noncontrolling interest	14,703		14,910
Noncontrolling Interest
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Noncontrolling interest investment	$ 0		$ 15,373

Goodwill and Intangible Asset48

Goodwill and Intangible Assets Goodwill Roll Forward (Details) $ in Thousands	3 Months Ended
	Mar. 26, 2016USD ($)
Goodwill [Roll Forward]
Balance as of December 26, 2015	$ 191,560
Foreign currency translation adjustments	1,938
Accumulated impairment loss	0
Balance as of March 26, 2016	$ 193,498

Goodwill and Intangible Asset49

Goodwill and Intangible Assets (Details) $ in Millions	3 Months Ended
	Mar. 26, 2016USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization expense	$ 6.5
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, period increase (decrease)	$ 3.9
Maximum finite-lived intangible asset, useful life	10 years

Goodwill and Intangible Asset50

Goodwill and Intangible Assets - Purchased Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 26, 2016	Dec. 26, 2015
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 150,623	$ 145,305
Accumulated Amortization	(16,185)	(9,507)
Net Carrying Amount	134,438	135,798
Intangible assets gross	167,496	165,826
Intangible assets	$ 151,311	$ 156,319
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years 6 months	5 years 8 months 16 days
Trade name
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 241	$ 239
Accumulated Amortization	(241)	(168)
Net Carrying Amount	$ 0	$ 71
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	0 days	1 month 24 days
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 50,497	$ 49,991
Accumulated Amortization	(3,798)	(2,197)
Net Carrying Amount	$ 46,699	$ 47,794
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	7 years 4 months 24 days	7 years 7 months 24 days
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 99,066	$ 94,256
Accumulated Amortization	(11,620)	(6,629)
Net Carrying Amount	$ 87,446	$ 87,627
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	4 years 6 months	4 years 7 months 24 days
Other intangible assets
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 819	$ 819
Accumulated Amortization	(526)	(513)
Net Carrying Amount	$ 293	$ 306
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years 4 months 24 days	5 years 7 months 13 days
In-process technology
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets	$ 16,873	$ 20,521

Goodwill and Intangible Asset51

Goodwill and Intangible Assets Future Amortization Expense (Details) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Net Carrying Amount	$ 134,438	$ 135,798
Remainder of 2016	19,547
2,017	26,064
2,018	26,064
2,019	25,999
2,020	19,303
2021 and Thereafter	$ 17,461

Balance Sheet Details Selected

Balance Sheet Details Selected Balance Sheet Items (Details) - USD ($) $ in Thousands		Mar. 26, 2016	Dec. 26, 2015
Inventory:
Raw materials		$ 33,085	$ 27,879
Work in process		59,394	52,599
Finished goods		97,265	94,221
Total inventory		189,744	174,699
Property, plant and equipment, net:
Property, plant and equipment, gross		306,288	294,716
Less accumulated depreciation and amortization		(190,916)	(183,855)
Total property, plant and equipment, net		115,372	110,861
Accrued expenses:
Loss contingency related to non-cancelable purchase commitments		6,160	6,821
Professional and other consulting fees		5,168	5,363
Taxes payable		2,560	3,295
Royalties		4,449	4,290
Other accrued expenses		14,982	13,967
Total accrued expenses		33,319	33,736
Computer hardware
Property, plant and equipment, net:
Property, plant and equipment, gross		12,062	11,097
Computer software
Property, plant and equipment, net:
Property, plant and equipment, gross	[1]	22,676	22,548
Laboratory and manufacturing equipment
Property, plant and equipment, net:
Property, plant and equipment, gross		197,561	189,168
Furniture and fixtures
Property, plant and equipment, net:
Property, plant and equipment, gross		2,018	1,897
Leasehold improvements
Property, plant and equipment, net:
Property, plant and equipment, gross		41,545	38,946
Construction in progress
Property, plant and equipment, net:
Property, plant and equipment, gross		30,426	31,060
Enterprise Resource Planning Systems
Property, plant and equipment, net:
Property, plant and equipment, gross		7,900	7,900
Total property, plant and equipment, net		$ 3,700	$ 4,000
[1]	Included in computer software at March 26, 2016 and December 26, 2015 were $7.9 million and $7.9 million, respectively, related to an enterprise resource planning ("ERP") system that the Company implemented during 2012. The unamortized ERP costs at March 26, 2016 and December 26, 2015 were $3.7 million and $4.0 million, respectively

Accumulated Other Comprehensi53

Accumulated Other Comprehensive Income - Summary of Changes in Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	$ 1,123
Net current-period other comprehensive income	3,651	$ 108
Ending balance	4,774
Unrealized Gain (Loss) on Other Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(506)
Net current-period other comprehensive income	383
Ending balance	(123)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	2,389
Net current-period other comprehensive income	3,268
Ending balance	5,657
Accumulated Tax Effect
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	(760)
Net current-period other comprehensive income	0
Ending balance	$ (760)

Basic and Diluted Net Income 54

Basic and Diluted Net Income Per Common Share - Computation of Net Income Per Common Share Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Numerator:
Net income	$ 12,015	$ 12,366
Denominator:
Basic weighted average common shares outstanding (in shares)	140,805	127,840
Effect of dilutive securities:
Employee equity plans (in shares)	3,822	6,569
Assumed conversion of convertible senior notes from conversion spread (in shares)	2,253	2,895
Diluted weighted average common shares outstanding (in shares)	146,880	137,304
Net income per common share attributable to Infinera Corporation
Basic (in usd per share)	$ 0.09	$ 0.10
Diluted (in usd per share)	$ 0.08	$ 0.09

Basic and Diluted Net Income 55

Basic and Diluted Net Income Per Common Share - Antidilutive Shares Excluded from Computation of Diluted Income Loss Per Share (Details) - shares shares in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	1,671	2,222
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	9	10
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	779	1,505
PSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	302	292
ESPP shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share computation (in shares)	581	415

Convertible Senior Notes - Addi

Convertible Senior Notes - Additional Information (Details)	1 Months Ended	3 Months Ended
	May. 31, 2013USD ($)d	Mar. 26, 2016USD ($)	Mar. 25, 2016$ / shares	Dec. 26, 2015USD ($)	Mar. 28, 2015	May. 30, 2013USD ($)$ / shares
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt Issuance Costs, Gross						$ 5,500,000
Purchase price as a percentage on principal amount of the notes upon the occurrence of a fundamental change	100.00%
Remaining life of note		2 years
Deferred tax liability		$ 35,436,000		$ 35,731,000
Total estimated fair value of the notes		$ 204,900,000
Closing price of common stock (in usd per share) | $ / shares			$ 15.30
1.75% Convertible Senior Notes Due June 1, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt instrument interest percentage		1.75%			1.75%	1.75%
Proceeds from issuance of debt, net		$ 144,500,000
Initial conversion rate per $1,000 principal amount of Notes	0.0794834
Initial conversion price (in usd per share) | $ / shares						$ 12.58
Debt instrument, convertible, if-converted value in excess of principal		32,400,000
Deferred tax liability		$ 17,000,000
Additional effective rate of interest to be used on amortized carrying value		10.23%			10.23%
Convertible Senior Notes, Conversion Circumstance One
Accounts, Notes, Loans and Financing Receivable [Line Items]
Threshold trading days for debt instrument conversion | d	20
Convertible threshold consecutive trading days	30 days	30 days
Convertible threshold minimum percentage	130.00%
Convertible Senior Notes, Conversion Circumstance Two
Accounts, Notes, Loans and Financing Receivable [Line Items]
Convertible threshold consecutive trading days	5 days
Convertible threshold business days | d	5
Debt instrument, convertible, if-converted value in excess of principal	$ 1,000
Convertible, threshold maximum percentage	98.00%
Other Noncurrent Assets | Accounting Standards Update 2015-03
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt issuance costs				(2,100,000)
Long-term Debt | Accounting Standards Update 2015-03
Accounts, Notes, Loans and Financing Receivable [Line Items]
Debt issuance costs				$ 2,100,000

Convertible Senior Notes - Comp

Convertible Senior Notes - Components of Convertible Senior Notes (Details) - USD ($)		Mar. 26, 2016	Dec. 26, 2015	May. 30, 2013
Debt Instrument [Line Items]
Unamortized discount	[1]	$ (22,287,000)	$ (24,560,000)
Unamortized issuance cost	[1]	(1,918,000)	(2,113,000)
1.75% Convertible Senior Notes Due June 1, 2018
Debt Instrument [Line Items]
Principal amount				$ 150,000,000
Net carrying amount		125,795,000	123,327,000
Debt Instrument Net Equity Component Carrying Amount		43,341,000	43,341,000
1.75% Convertible Senior Notes Due June 1, 2018 | Additional Paid-in Capital
Debt Instrument [Line Items]
Debt discount related to value of conversion option		45,000,000	45,000,000
Debt issuance cost		(1,659,000)	(1,659,000)
1.75% Convertible Senior Notes Due June 1, 2018 | Long-term Debt
Debt Instrument [Line Items]
Principal amount		$ 150,000,000	$ 150,000,000
[1]	Unamortized debt conversion discount and issuance costs will be amortized over the remaining life of the Notes, which is approximately two years.

Convertible Senior Notes - Inte

Convertible Senior Notes - Interest Expense Recognized Related to Notes Prior to Capitalization of Interest (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Debt Disclosure [Abstract]
Contractual interest expense	$ 656	$ 656
Amortization of debt issuance costs	196	177
Amortization of debt discount	2,274	2,057
Total interest expense	$ 3,126	$ 2,890

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 26, 2016USD ($)$ / sharesshares	Mar. 28, 2015USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Price | $ / shares	$ 15.30
Granted options to employees to purchase shares of common stock (in shares)	14,600
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant cost (in shares)	604
Amortization of stock-based compensation | $	$ 6.1	$ 5.2
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant cost (in shares)	424
PSUs | Two Thousand And Seven Equity Incentive Plan | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges of number of shares issued on vesting of PSUs	0
PSUs | Two Thousand And Seven Equity Incentive Plan | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ranges of number of shares issued on vesting of PSUs	2
PSUs | Existing Employees | Vesting 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of grants based on shareholder return of common stock price versus designated index	1 year
PSUs | Existing Employees | Vesting 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of grants based on shareholder return of common stock price versus designated index	2 years
PSUs | Existing Employees | Vesting 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of grants based on shareholder return of common stock price versus designated index	3 years
Performance Stock Unit Grants
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amortization of stock-based compensation | $	$ 0.8	$ 0.9

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Company's Equity Award Activity - Options (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,987	$ 7,208
Share Price	$ 15.30
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7	$ 70
Number of Stock Options
Number of Options, beginning balance (in shares)	2,511
Number of Options, granted (in shares)	0
Number of Options, exercised (in shares)	(57)
Number of Options, canceled (in shares)	0
Number of Options, ending balance (in shares)	2,454
Number of Options, vested and expected to vest (in shares)	2,454
Number of Options, exercisable (in shares)	2,443
Weighted-Average Exercise Price Per Share
Weighted-Average Exercise Price Per Share, beginning balance (in usd per share)	$ 7.26
Weighted-Average Exercise Per Share, Options granted (in usd per share)	0
Weighted-Average Exercise Price Per Share, Options exercised (in usd per share)	5.14
Weighted-Average Exercise Price Per Share, Options canceled (in usd per share)	0
Weighted-Average Exercise Price Per Share, ending balance (in usd per share)	7.31
Average Exercise Price Per Share, Exercisable (in usd per share)	$ 7.30
Aggregate Intrinsic Value
Aggregate Intrinsic Value, beginning balance	$ 28,288
Aggregate Intrinsic Value, Options exercised	600
Aggregate Intrinsic Value, ending balance	19,672
Aggregate Intrinsic Value, Vested and expected to vest	19,670
Aggregate Intrinsic Value, Exercisable	$ 19,600

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Company's Equity Award Activity - RSUs (Details) - Restricted Stock Units $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 26, 2016USD ($)$ / sharesshares
Number of Restricted Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)	4,932
Number of shares available for grant cost (in shares)	604
Number of Restricted/Performance Stock Units, released (in shares)	(279)
Number of Restricted Stock Units, canceled (in shares)	(142)
Number of Restricted/Performance Stock Units, ending balance (in shares)	5,115
Number of Restricted Stock Units, Expected to vest (in shares)	4,855
Weighted- Average Grant Date Fair Value Per Share
Weighted-Average Grant Date Fair Value Per Share, beginning balance (in usd per share) | $ / shares	$ 12.76
Weighted-average fair value, granted (in usd per share) | $ / shares	15.43
Weighted-Average Grant Date Fair Value Per Share, released (in usd per share) | $ / shares	9.75
Weighted-Average Grant Date Fair Value Per Share, canceled (in usd per share) | $ / shares	12.98
Weighted-Average Grant Date Fair Value Per Share, ending balance (in usd per share) | $ / shares	$ 13.23
Aggregate Intrinsic Value
Aggregate Intrinsic Value, beginning balance | $	$ 91,285
Aggregate Intrinsic Value, RSUs released | $	4,022
Aggregate Intrinsic Value, ending balance | $	78,263
Aggregate Intrinsic Value, Expected to vest | $	$ 74,278

Stockholders' Equity - Summar62

Stockholders' Equity - Summary of Company's Equity Award Activity - PSUs (Details) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended	12 Months Ended
		Mar. 26, 2016USD ($)$ / sharesshares	Dec. 26, 2015USD ($)$ / sharesshares	Dec. 27, 2014$ / shares	Dec. 28, 2013$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Price | $ / shares		$ 15.30
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SPGIIPTR Index Expected Volatility Rate		18.00%		25.00%
NASDAQ Telecom Composite Index, Expected Volatility Rate					23.00%
Volatility		55.00%	48.00%		55.00%
Risk-free interest rate		0.95%			0.42%
Correlation With SPGIIPTR Index			0.52	0.60
Correlation with NASDAQ Telecom Composite Index		0.58			0.56
Number of Performance Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)		731
Number of shares available for grant cost (in shares)		424
Number of Restricted/Performance Stock Units, released (in shares)		(462)
Number of Restricted Stock Units, canceled (in shares)		(71)
Number of Restricted/Performance Stock Units, ending balance (in shares)		776	731
Number of Restricted Stock Units, Expected to vest (in shares)		744
Weighted- Average Grant Date Fair Value Per Share
Weighted-Average Grant Date Fair Value Per Share, beginning balance (in usd per share) | $ / shares		$ 12.35
Weighted-average fair value, granted (in usd per share) | $ / shares		15.29
Weighted-Average Grant Date Fair Value Per Share, released (in usd per share) | $ / shares		9.43
Weighted-Average Grant Date Fair Value Per Share, canceled (in usd per share) | $ / shares		15.65
Weighted-Average Grant Date Fair Value Per Share, ending balance (in usd per share) | $ / shares		$ 14.51	$ 12.35
Aggregate Intrinsic Value
Aggregate Intrinsic Value, beginning balance | $		$ 13,540
Aggregate Intrinsic Value, PSUs released | $		6,650
Aggregate Intrinsic Value, ending balance | $		11,865	$ 13,540
Aggregate Intrinsic Value, Expected to vest | $		$ 11,384
Additional Grants For Performance
Number of Performance Stock Units
Number of shares available for grant cost (in shares)	[1],[2]	154
Weighted- Average Grant Date Fair Value Per Share
Weighted-average fair value, granted (in usd per share) | $ / shares	[1]	$ 9.43
Fiscal Year 2013 Grant [Member] | PSUs
Number of Performance Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)		147
Number of shares available for grant cost (in shares)		0
Number of Restricted/Performance Stock Units, released (in shares)		(211)
Number of Restricted Stock Units, canceled (in shares)		(6)
Number of Restricted/Performance Stock Units, ending balance (in shares)		0	147
Fiscal Year 2013 Grant [Member] | Additional Grants For Performance
Number of Performance Stock Units
Number of shares available for grant cost (in shares)	[2]	70
Fiscal Year 2014 Grant [Member] | PSUs
Number of Performance Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)		260
Number of shares available for grant cost (in shares)		0
Number of Restricted/Performance Stock Units, released (in shares)		(158)
Number of Restricted Stock Units, canceled (in shares)		(8)
Number of Restricted/Performance Stock Units, ending balance (in shares)		147	260
Fiscal Year 2014 Grant [Member] | Additional Grants For Performance
Number of Performance Stock Units
Number of shares available for grant cost (in shares)	[2]	53
Fiscal Year 2015 Grant [Member] | PSUs
Number of Performance Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)		324
Number of shares available for grant cost (in shares)		0
Number of Restricted/Performance Stock Units, released (in shares)		(93)
Number of Restricted Stock Units, canceled (in shares)		(57)
Number of Restricted/Performance Stock Units, ending balance (in shares)		205	324
Fiscal Year 2015 Grant [Member] | Additional Grants For Performance
Number of Performance Stock Units
Number of shares available for grant cost (in shares)	[2]	31
Fiscal Year 2016 Grant [Member] | PSUs
Number of Performance Stock Units
Number of Restricted/Performance Stock Units, beginning balance (in shares)		0
Number of shares available for grant cost (in shares)		424
Number of Restricted/Performance Stock Units, released (in shares)		0
Number of Restricted Stock Units, canceled (in shares)		0
Number of Restricted/Performance Stock Units, ending balance (in shares)		424	0
Fiscal Year 2016 Grant [Member] | Additional Grants For Performance
Number of Performance Stock Units
Number of shares available for grant cost (in shares)	[2]	0
Minimum | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SPGIIPTR Index Expected Volatility Rate			18.00%
Volatility				49.00%
Risk-free interest rate			0.97%	0.66%
Weighted- Average Grant Date Fair Value Per Share
Weighted-average fair value, granted (in usd per share) | $ / shares		$ 12.10	$ 18.08	$ 6.59	$ 6.27
Maximum | PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SPGIIPTR Index Expected Volatility Rate			19.00%
Volatility				50.00%
Risk-free interest rate			1.10%	0.71%
Weighted- Average Grant Date Fair Value Per Share
Weighted-average fair value, granted (in usd per share) | $ / shares		$ 16.62	$ 19.29	$ 7.60	$ 7.06
[1]	Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts.
[2]	Represents the additional PSUs awarded resulting from the achievement of performance goals above the performance targets established at grant since the original grants were at 100% of target amounts.

Stockholders' Equity - Total St

Stockholders' Equity - Total Stock Based Compensation Cost for Instruments Granted but Not Yet Amortized (Details) $ in Thousands	3 Months Ended
	Mar. 26, 2016USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, Unrecognized Compensation Expense, Net	$ 40
Stock options, Weighted-Average Period (in years)	1 year 9 months 18 days
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Expense, Net	$ 42,653
Weighted-Average Period (in years)	2 years 5 months 12 days
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Expense, Net	$ 7,962
Weighted-Average Period (in years)	1 year 9 months 18 days

Stockholders' Equity - Estimate

Stockholders' Equity - Estimated Fair Value of ESPP Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 7,987	$ 7,208
Employee Stock Purchase Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility	56.00%	53.00%
Risk-free interest rate	0.52%	0.13%
Expected life	6 months	6 months
Estimated fair value (in usd per share)	$ 4.53	$ 5.15
Stock-based compensation expense	$ 1,242	$ 1,051

Stockholders' Equity - Ranges o

Stockholders' Equity - Ranges of Estimated Values of Stock Options and Performance-Based Stock Options Granted (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense	$ 7,987	$ 7,208

Stockholders' Equity - Summar66

Stockholders' Equity - Summary of Effects of Stock-Based Compensation on Company's Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Stock-Based Compensation Effects in Inventory
Effects Of Stock Based Compensation [Line Items]
Effects Of Stock Based Compensation	$ 3,282	$ 3,129
Stock-Based Compensation Effects in Deferred Inventory Cost
Effects Of Stock Based Compensation [Line Items]
Effects Of Stock Based Compensation	13	13
Stock-Based Compensation Effects in Fixed Assets
Effects Of Stock Based Compensation [Line Items]
Effects Of Stock Based Compensation	$ 87	$ 93

Stockholders' Equity - Summar67

Stockholders' Equity - Summary of Effects of Stock-Based Compensation on Company's Statements of Operations (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 26, 2016	Mar. 28, 2015
Effects Of Stock Based Compensation [Line Items]
Stock-based compensation effects included in net income before income taxes		$ 7,128	$ 6,447
Cost of revenue - amortization from balance sheet	[1]	859	761
Stock-based compensation expense		7,987	7,208
Cost of revenue
Effects Of Stock Based Compensation [Line Items]
Stock-based compensation effects included in net income before income taxes		673	482
Research and development
Effects Of Stock Based Compensation [Line Items]
Stock-based compensation effects included in net income before income taxes		2,321	2,578
Sales and marketing
Effects Of Stock Based Compensation [Line Items]
Stock-based compensation effects included in net income before income taxes		2,235	1,721
General and administration
Effects Of Stock Based Compensation [Line Items]
Stock-based compensation effects included in net income before income taxes		$ 1,899	$ 1,666
[1]	Stock-based compensation expense deferred to inventory and deferred inventory costs in prior periods and recognized in the current period.

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 26, 2016	Mar. 28, 2015
Business Acquisition [Line Items]
Provision (benefit) for income taxes	$ 216	$ 616
Pre-tax income (loss)	12,024	$ 12,982
Income tax benefit increase (decrease)	1,100
Transmode
Business Acquisition [Line Items]
Provision (benefit) for income taxes	(1,500)
Purchase accounting amortization expense	$ 7,000

Segment Information - Revenue

Segment Information - Revenue and Long-Lived Assets by Geographic Region (Details) $ in Thousands	3 Months Ended
	Mar. 26, 2016USD ($)segment	Mar. 28, 2015USD ($)
Segment Reporting [Abstract]
Number of reporting segments | segment	1
Number of operating segments | segment	1
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 244,818	$ 186,862
Operating Segments | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	174,515	127,003
Operating Segments | Other Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	3,259	7,086
Operating Segments | Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	177,774	134,089
Operating Segments | Europe, Middle East and Africa
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	59,876	45,879
Operating Segments | Asia Pacific and Japan
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 7,168	$ 6,894

Segment Information - Property,

Segment Information - Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 26, 2016	Dec. 26, 2015
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	$ 115,372	$ 110,861
Operating Segments | United States
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	106,833	102,702
Operating Segments | Other Americas
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	301	173
Operating Segments | Americas
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	107,134	102,875
Operating Segments | Europe, Middle East and Africa
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	5,618	5,417
Operating Segments | Asia Pacific and Japan
Geographic Information For Property Plant And Equipment [Line Items]
Total property, plant and equipment, net	$ 2,620	$ 2,569

Guarantees - Additional Informa

Guarantees - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 26, 2016	Dec. 26, 2015
Guarantor Obligations [Line Items]
Software warranty period	90 days
Outstanding standby letters of credit	$ 5.2	$ 5.2
Debt instrument, collateral amount	4.8	4.8
Banker's Guarantees Or Performance Bonds
Guarantor Obligations [Line Items]
Line of credit facility, maximum borrowing capacity	1.5	1.5
Proceeds from lines of credit	0.3	0.3
Letter of Credit
Guarantor Obligations [Line Items]
Customer proposal guarantee	3.1	3.1
Value added tax license	1.2	1.2
Property leases	$ 0.9	$ 0.9
Minimum
Guarantor Obligations [Line Items]
Product warranty period	1 year
Maximum
Guarantor Obligations [Line Items]
Product warranty period	5 years

Guarantees - Activity Related t

Guarantees - Activity Related to Product Warranty (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 26, 2016	Mar. 28, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Beginning balance		$ 38,844	$ 27,040
Charges to operations		6,754	5,348
Utilization		(4,987)	(1,818)
Change in estimate	[1]	(612)	(5,031)
Balance at the end of the period		$ 39,999	$ 25,539
[1]	The Company records hardware warranty liabilities based on the latest quality and cost information available as of that date. The changes in estimate shown here are due to changes in overall actual failure rates, the mix of new versus used units related to replacement of failed units, and changes in the estimated cost of repair. As the Company's products mature over time, failure rates and repair costs generally decline leading to favorable changes in warranty reserves.