Neophotonics (NPTN) 10-K 15 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 29, 2016	Jun. 30, 2015
Document Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	NPTN
Entity Registrant Name	NEOPHOTONICS CORP
Entity Central Index Key	1,227,025
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		41,100,326
Entity Public Float			$ 266,804,000

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 76,088	$ 43,035
Short-term investments	23,294
Restricted cash and investments	2,660	5,504
Accounts receivable, net of allowance for doubtful accounts	83,161	77,597
Inventories	65,602	57,347
Prepaid expenses and other current assets	12,393	15,540
Total current assets	263,198	199,023
Property, plant and equipment, net	62,618	57,657
Restricted cash and investments, non-current		15,750
Purchased intangible assets, net	9,852	10,263
Goodwill	1,115
Other long-term assets	5,095	3,591
Total assets	341,878	286,284
Current liabilities:
Accounts payable	50,620	48,949
Notes payable and short-term borrowing	32,657	22,771
Current portion of long-term debt	760	2,445
Accrued and other current liabilities	27,950	22,728
Total current liabilities	111,987	96,893
Long-term debt, net of current portion	10,759	20,891
Deferred income tax liabilities	88	1,818
Other noncurrent liabilities	7,388	7,226
Total liabilities	$ 130,222	$ 126,828
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.0025 par value, 10,000 shares authorized, no shares issued or outstanding
Common stock, $0.0025 par value, 100,000 shares authorized At December 31, 2015, 40,986 shares issued and outstanding; at December 31, 2014, 32,752 shares issued and outstanding	$ 102	$ 82
Additional paid-in capital	511,750	456,189
Accumulated other comprehensive (loss) income	(1,723)	5,326
Accumulated deficit	(298,473)	(302,141)
Total stockholders' equity	211,656	159,456
Total liabilities and stockholders' equity	$ 341,878	$ 286,284

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Dec. 31, 2015	Dec. 31, 2014
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0025	$ 0.0025
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0025	$ 0.0025
Common stock, shares authorized	100,000	100,000
Common stock, shares issued	40,986	32,752
Common stock, shares outstanding	40,986	32,752

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenue	$ 339,439	$ 306,177	$ 282,242
Cost of goods sold	240,358	235,059	217,069
Gross profit	99,081	71,118	65,173
Operating expenses:
Research and development	44,533	45,959	45,853
Sales and marketing	15,823	13,725	14,242
General and administrative	31,635	31,570	30,012
Amortization of purchased intangible assets	1,791	1,502	1,532
Acquisition-related costs	934	615	5,406
Asset impairment charge	368	1,130
Restructuring charges	44	662	775
Adjustment to fair value of contingent consideration			1,026
Escrow settlement gain		(4,913)
Total operating expenses	95,128	90,250	98,846
Income (loss) from operations	3,953	(19,132)	(33,673)
Interest income	121	189	348
Interest expense	(1,243)	(1,269)	(996)
Other income, net	3,941	3,012	1,186
Total interest and other income (expense), net	2,819	1,932	538
Income (loss) before income taxes	6,772	(17,200)	(33,135)
Provision for income taxes	(3,104)	(2,519)	(1,204)
Net income (loss)	$ 3,668	$ (19,719)	$ (34,339)
Basic net income (loss) per share	$ 0.10	$ (0.61)	$ (1.11)
Diluted net income (loss) per share	$ 0.09	$ (0.61)	$ (1.11)
Weighted average shares used to compute basic net income (loss) per share	37,421	32,109	31,000
Weighted average shares used to compute diluted net income (loss) per share	38,686	32,109	31,000

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 3,668	$ (19,719)	$ (34,339)
Other comprehensive loss:
Foreign currency translation adjustments net of zero tax	(6,987)	(6,411)	41
Unrealized (losses) gains on available-for-sale securities, net of zero tax	(35)	3	(65)
Defined benefit pension plans:
Loss arising during the period	(40)	(113)	(191)
Curtailments, settlements and other		191
Tax	13	(31)	73
Total other comprehensive loss	(7,049)	(6,361)	(142)
Comprehensive loss	$ (3,381)	$ (26,080)	$ (34,481)

Consolidated Statements of Com6

Consolidated Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0
Unrealized gains (losses) on available-for-sale securities, tax	$ 0	$ 0	$ 0

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional paid-in capital [Member]	Accumulated other comprehensive income (loss) [Member]	Accumulated deficit [Member]	Total
Balances at Dec. 31, 2012	$ 76	$ 438,858	$ 11,829	$ (248,083)	$ 202,680
Beginning (in shares) at Dec. 31, 2012	30,546,000
Comprehensive loss			(142)	(34,339)	(34,481)
Issuance of common stock upon exercise of stock options	$ 1	1,212			1,213
Issuance of common stock upon exercise of stock options (in shares)	261,000
Issuance of common stock under employee stock purchase plan	$ 2	2,155			2,157
Issuance of common stock under employee stock purchase plan (in shares)	488,000
Issuance of common stock for vested restricted stock units (in shares)	277,000
Tax withholding related to vesting of restricted stock units		(565)			(565)
Stock-based compensation costs		5,807			5,807
Balances at Dec. 31, 2013	$ 79	447,467	11,687	(282,422)	176,811
Beginning (in shares) at Dec. 31, 2013	31,572,000
Comprehensive loss			(6,361)	(19,719)	(26,080)
Issuance of common stock upon exercise of stock options	$ 1	738			739
Issuance of common stock upon exercise of stock options (in shares)	174,000
Issuance of common stock under employee stock purchase plan	$ 1	1,833			1,834
Issuance of common stock under employee stock purchase plan (in shares)	591,000
Issuance of common stock for vested restricted stock units	$ 1	(1)
Issuance of common stock for vested restricted stock units (in shares)	524,000
Tax withholding related to vesting of restricted stock units		(387)			(387)
Tax withholding related to vesting of restricted stock units (in shares)	(109,000)
Stock-based compensation costs		6,539			6,539
Balances at Dec. 31, 2014	$ 82	456,189	5,326	(302,141)	159,456
Beginning (in shares) at Dec. 31, 2014	32,752,000
Comprehensive loss			(7,049)	3,668	(3,381)
Issuance of common stock from public stock offering, net of discount and offering costs	$ 17	45,621			45,638
Issuance of common stock from public stock offering, net of discount and offering costs (in shares)	6,867,000
Issuance of common stock upon exercise of stock options	$ 1	1,177			$ 1,178
Issuance of common stock upon exercise of stock options (in shares)	304,000				304,385
Issuance of common stock under employee stock purchase plan	$ 1	1,538			$ 1,539
Issuance of common stock under employee stock purchase plan (in shares)	600,000
Issuance of common stock for vested restricted stock units	$ 1	(1)
Issuance of common stock for vested restricted stock units (in shares)	558,000
Tax withholding related to vesting of restricted stock units		(727)			(727)
Tax withholding related to vesting of restricted stock units (in shares)	(95,000)
Stock-based compensation costs		7,953			7,953
Balances at Dec. 31, 2015	$ 102	$ 511,750	$ (1,723)	$ (298,473)	$ 211,656
Beginning (in shares) at Dec. 31, 2015	40,986,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income (loss)	$ 3,668	$ (19,719)	$ (34,339)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	22,875	23,403	20,381
Stock-based compensation expense	7,763	6,841	5,736
Deferred taxes	(641)	1,175	(469)
Investment and debt related amortization	296	86	1,003
Loss on disposal of property and equipment	394	162	710
Asset impairment charges	368	1,130
Adjustment to fair value of penalty payment derivative	(141)	291	101
Adjustment to fair value of contingent consideration			1,026
Allowance for doubtful accounts	640	(266)	(253)
Write-down of inventories	6,486	1,517	3,207
Foreign currency remeasurement and other, net	(2,992)	(2,343)	(667)
Change in assets and liabilities, net of effects of acquisitions:
Accounts receivable	2,529	(13,269)	7,234
Inventories	(14,899)	4,990	(10,458)
Prepaid expenses and other assets	(1,691)	(5,912)	(1,795)
Accounts payable	(4,692)	979	7,712
Accrued and other liabilities	6,175	484	5,382
Net cash provided by (used in) operating activities	26,138	(451)	4,511
Cash flows from investing activities
Purchase of property, plant and equipment	(16,837)	(11,027)	(19,566)
Proceeds from sale of property, plant and equipment and other assets	245	9	92
Purchase of marketable securities	(37,130)	(9,662)	(58,860)
Proceeds from sale of marketable securities	18,103	9,634	53,847
Proceeds from maturity of securities	4,000	9,448	50,358
Decrease (increase) in restricted cash	10,135	(10,847)	561
Acquisition of business	(422)	(1,500)	(13,128)
Net cash (used in) provided by investing activities	(21,906)	(13,945)	13,304
Cash flows from financing activities
Proceeds from (payment for) public stock offering, net of discount and offering costs	45,648	(10)
Proceeds from exercise of stock options and issuance of stock under ESPP	2,717	2,571	3,370
Tax withholding on restricted stock units	(727)	(387)	(565)
Proceeds from bank loans	80,256	18,089	26,443
Repayment of bank and acquisition-related loans	(94,032)	(18,423)	(24,110)
Proceeds from issuance of notes payable	21,259	25,264	19,543
Repayment of notes payable	(25,498)	(22,090)	(22,166)
Payment of acquisition-related contingent consideration		(1,985)
Net cash provided by financing activities	29,623	3,029	2,515
Effect of exchange rates on cash and cash equivalents	(802)	(2,699)	(169)
Net increase (decrease) in cash and cash equivalents	33,053	(14,066)	20,161
Cash and cash equivalents at the beginning of the period	43,035	57,101	36,940
Cash and cash equivalents at the end of the period	76,088	43,035	57,101
Supplemental disclosure of cash flow information:
Cash paid for interest	878	1,176	837
Cash paid for income taxes	264	3,919	1,013
Supplemental disclosure of noncash investing and financing activities:
Modification of bank loan with Comerica	15,786
Issuance of note to seller of acquired business	15,482		11,130
Transfer of restricted investments to short-term investments	8,296
Transfer of short-term investments to restricted investments		8,297
Unpaid deferred offering costs		364
Changes in unpaid property, plant and equipment	$ (396)	$ (746)	$ (1,397)

The Company and basis of presen

The Company and basis of presentation	12 Months Ended
	Dec. 31, 2015
The Company and basis of presentation
The Company and basis of presentation	1. The Company and basis of presentation Business and organization NeoPhotonics Corporation and its subsidiaries (NeoPhotonics or the Company) develops, manufactures and sells optoelectronic products that transmit, receive and switch high speed digital optical signals for communications networks. The Company sells its products worldwide, primarily to leading network equipment manufacturers. Certain Significant Risks and Uncertainties The Company operates in a dynamic industry and, accordingly, can be affected by a variety of factors. For example, any of the following areas could have a negative effect on the Company in terms of its future financial position, results of operations or cash flows: the general state of the U.S. and world economies, the highly cyclical nature of the industries the Company serves; the loss of any of a small number of its larger customers; ability to obtain additional financing; inability to meet certain debt covenants; failure to successfully integrate completed acquisitions; fundamental changes in the technology underlying the Company’s products; the hiring, training and retention of key employees; successful and timely completion of product design efforts; and new product design introductions by competitors. Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation. Reclassification Reclassification has been made within other accrued expense amount to separate income and other taxes payable and accrued warranty from other in the prior year (Note 8) in order to conform to the current year’s presentation .

Summary of significant accounti

Summary of significant accounting policies	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Summary of significant accounting policies	2. Summary of significant accounting policies Use of estimates The preparation of financial statements in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported revenue and expenses during the reporting period. Significant estimates made by management include: the useful lives of property, plant and equipment and intangible assets as well as future cash flows to be generated by those assets; fair values of identifiable assets acquired and liabilities assumed in business combinations; allowances for doubtful accounts; valuation allowances for deferred tax assets; write off of excess and obsolete inventories; the valuation of the penalty payment derivative and the valuations and recognition of stock-based compensation, among others. Actual results could differ from these estimates. Concentration of credit risk and significant customers Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash and cash equivalents and trade accounts receivable. The Company’s investment policy requires cash and cash equivalents to be placed with high-credit quality institutions and limits on the amount of credit risk from any one issuer. The Company performs ongoing credit evaluations of its customers’ financial condition whenever deemed necessary and generally does not require collateral. The Company maintains an allowance for doubtful accounts based upon the expected collectability of all accounts receivable, which takes into consideration an analysis of historical bad debts, specific customer creditworthiness and current economic trends. For the year ended December 31, 2015, two customers accounted for 44% and 21% of the Company’s total revenue. For the year ended December 31, 2014, three customers accounted for 38% , 15% and 10% of the Company’s total revenue. For the year ended December 31, 2013, three customers accounted for 27% , 16% and 14% of the Company’s total revenue. No other customers accounted for 10% or more of total revenue in any year presented. As of December 31, 2015, one customer accounted for 59% of the Company’s total accounts receivable and as of December 31, 2014, three customers accounted for 26% , 19% and 10% of the Company’s total accounts receivable. No other customers accounted for 10% or more of total accounts receivable as of December 31, 2015 or 2014. Restricted cash As a condition of the notes payable lending arrangements of the Company’s subsidiaries in China and, in 2014, the Company’s bank term loan agreement, the Company is required to keep a compensating balance at the issuing banks. These balances have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash and investments in the Company’s consolidated balance sheets. As of December 31, 2015 and 2014, the amount of restricted cash and investments was $ 2.7 million and $21. 3 million , respectively. Cash, cash equivalents and investments Highly liquid investments with a maturity of 90 days or less at the date of purchase are considered cash equivalents, with the exception of money market funds and commercial paper which are classified as short-term investments. The Company regularly reviews its investment portfolio to identify and evaluate investments that have indications of possible impairment. Factors considered in determining whether a loss is other-than-temporary include: the length of time and extent to which the fair market value has been lower than the cost basis, the financial condition and near-term prospects of the investee, credit quality, likelihood of recovery, and the Company’s ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in fair market value. Unrealized gains and losses, net of tax, are included in accumulated other comprehensive (loss) income as a separate component of stockholders’ equity on the consolidated balance sheets. The amortization of premiums and discounts on the investments, and realized gains and losses on available-for-sale securities are included in other income (expense), net in the consolidated statements of operations. The Company uses the specific-identification method to determine cost in calculating realized gains and losses upon sale of its marketable securities. Marketable securities are reported at fair value and are classified as available-for-sale investments in our current assets because they represent investments of cash available for current operations. Fair Value Measurements Fair value is defined as the price at which an asset could be exchanged in a current transaction between knowledgeable, willing parties. A liability’s fair value is defined as the amount that would be paid to transfer the liability to a new obligor, not the amount that would be paid to settle the liability with the creditor. Where available, fair value is based on observable market prices or parameters or derived from such prices or parameters. Where observable prices or inputs are not available, valuation models are applied. These valuation techniques involve some level of management estimation and judgment, the degree of which is dependent on the price transparency for the instruments or market and the instruments’ complexity. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative accounting guidance describes a fair value hierarchy based on three levels of inputs that may be used to measure fair value, of which the first two are considered observable and the last is considered unobservable. These levels of inputs are as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date. Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3—Unobservable inputs that reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. For marketable securities measured at fair value using Level 2 inputs, we review trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical securities is not available, we use market pricing and other observable market inputs for similar securities obtained from various third party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data. Accounts receivable Accounts receivable include trade receivables and notes receivable from customers. The notes are generally due within six months. The Company receives notes receivable in exchange for accounts receivable from certain customers in China that are secured by the customer’s affiliated financial institution. An allowance for doubtful accounts is calculated based on the aging of the Company’s trade receivables, historical experience, and management judgment. The Company writes off trade receivables against the allowance when management determines a balance is uncollectible and is no longer actively pursuing collection of the receivable. Inventories Inventories consist of on-hand raw materials, work-in-progress inventories and finished goods. Raw materials and work-in-progress inventories are stored mainly on the Company’s premises. Finished goods are stored on the Company’s premises as well as on consignment at certain customer sites. Inventories are stated at the lower of standard cost, which approximates actual cost determined on the weighted average basis, or market value. Inventories are recorded using the first-in, first-out method. The Company routinely evaluates quantities and values of inventories in light of current market conditions and market trends, and records a write-down for quantities in excess of demand and product obsolescence. The evaluation may take into consideration historic usage, expected demand, anticipated sales price, new product development schedules, the effect new products might have on the sale of existing products, product obsolescence, customer concentrations, product merchantability and other factors. Market conditions are subject to change and actual consumption of inventory could differ from forecasted demand. The Company also regularly reviews the cost of inventories against their estimated market value and records a lower of cost or market write-down for inventories that have a cost in excess of estimated market value, resulting in a new cost basis for the related inventories which is not reversed. Business Combinations We allocate the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. When determining the fair values of assets acquired and liabilities assumed, management makes significant estimates and assumptions. Fair value estimates are based on the assumptions management believes a market participant would use in pricing the asset or liability. Critical estimates in valuing certain intangible assets include, but are not limited to, future expected cash flows from customer relationships and acquired patents and developed technology; and discount rates. Management’s estimates of fair value are based upon assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. Amounts recorded in a business combination may change during the measurement period, which is a period not to exceed one year from the date of acquisition, as additional information about conditions existing at the acquisition date becomes available. Goodwill Goodwill is reviewed for impairment annually in the fourth fiscal quarter or more frequently if events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable. The Company will assess the qualitative factors to determine whether it is more likely than not that the fair value of its single reporting operating unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment. If the Company determines that it is more likely than not that its fair value is less than its carrying amount, then the two-step goodwill impairment test is performed. The first step, identifying a potential impairment, compares the fair value of the reporting unit with its carrying amount. If the carrying amount exceeds its fair value, the second step would need to be performed; otherwise, no further steps are required. The second step, measuring the impairment loss, compares the implied fair value of the goodwill with the carrying amount of the goodwill. Any excess of the goodwill carrying amount over the implied fair value is recognized as an impairment loss, and the carrying value of goodwill is written down to fair value. The Company did not have any goodwill impairment in 2015. There was no goodwill as of December 31, 2014. Long-lived assets Property, plant and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization is computed using the straight-line method over the following estimated useful lives: Buildings 20 - 30 years Machinery and equipment 2 - 7 years Furniture, fixtures and office equipment 3 - 5 years Software 5 - 7 years Leasehold improvements life of the asset or lease term, if shorter Repairs and maintenance costs are expensed as incurred. Intangible assets acquired in a business combination are recorded at fair value. Identifiable finite-lived intangible assets are amortized over the period of estimated benefit using the straight-line method, reflecting the pattern of economic benefits associated with these assets. The estimated useful lives of the Company’s finite-lived intangible assets generally range from two to seven years. The acquired land use rights in China have an estimated useful life of 45 years. The carrying value of intangible assets and other long-lived assets is reviewed on a regular basis for the existence of facts or circumstances, both internally and externally, that may suggest impairment. Some factors which the Company considers to be triggering events for impairment review include a significant decrease in the market value of an asset, a significant change in the extent or manner in which an asset is used, a significant adverse change in the business climate that could affect the value of an asset, an accumulation of costs for an asset in excess of the amount originally expected, a current period operating loss or cash flow decline combined with a history of operating loss or cash flow uses or a projection that demonstrates continuing losses and a current expectation that, it is more likely than not, a long-lived asset will be disposed of at a loss before the end of its estimated useful life. If one or more of such facts or circumstances exist, the Company will evaluate the carrying value of long-lived assets to determine if impairment exists by comparing it to estimated undiscounted future cash flows over the remaining useful life of the assets. If the carrying value of the assets is greater than the estimated future cash flow, the assets are written down to the estimated fair value. The Company’s cash flow estimates contain management’s best estimates, using appropriate and customary assumptions and projections at the time. Any write-down would be treated as a permanent reduction in the carrying amount of the asset and an operating loss would be recognized. The Company recor ded asset impairment charges of $0.4 million in 2015 related to certain held-for-sale assets property, plant and equipment and $1.1 million in 2014 related to certain leasehold improvements. The Company had no asset impairment charge in 2013. Revenue recognition Revenue is derived from the sale of the Company’s products. The Company recognizes revenue provided that persuasive evidence of an arrangement exists, delivery has occurred, the price is fixed or determinable and collectability is reasonably assured. Contracts and/or customer purchase orders are used to determine the existence of an arrangement. Delivery is considered to have occurred when title and risk of loss have transferred to the customer. The price is equal to the amount invoiced to the customer and is not subject to adjustment and customers do not have the right of return. The Company evaluates the creditworthiness of its customers to determine that appropriate credit limits are established prior to the acceptance of an order. Revenue is recognized when the product is shipped and title has transferred to the buyer. The Company bears all costs and risks of loss or damage to the goods up to that point. On most orders, the Company’s shipment terms provide that title passes to the buyer upon shipment by the Company. Other shipment terms may provide that title passes to the buyer upon delivery of the goods to the buyer. Revenue related to the sale of consignment inventory at customer vendor managed locations is not recognized until the product is pulled from inventory stock by customers. Shipping and handling costs are included in the cost of goods sold. The Company presents revenue net of sales taxes and any similar assessments. Product warranties The Company generally provides warranties to cover defects in workmanship, materials and manufacturing for a period of one to three years to meet the stated functionality as agreed to in each sales arrangement. Products are tested against specified functionality requirements prior to delivery, but the Company nevertheless from time to time experiences claims under its warranty guarantees. The Company accrues for estimated warranty costs under those guarantees based upon historical experience, and for specific items, at the time their existence is known and the amounts are determinable. Research and development Research and development expense consists of personnel costs, including stock-based compensation expense, for the Company’s research and development personnel and product development costs, including engineering services, development software and hardware tools, depreciation of capital equipment and facility costs. Research and development costs are expensed as incurred. Advertising costs Advertising costs are expensed as incurred and, to date, have not been significant. Stock-based compensation The Company grants stock-based awards to employees, consultants and directors. The stock-based awards, including stock options, restricted stock units, employee stock purchase rights, stock appreciation units and market-based awards, are accounted for at estimated fair values. The Company generally determines the fair value of stock options and stock appreciation rights utilizing the Black-Scholes-Merton option-pricing model, or a lattice-binomial option-pricing model for stock-based awards with a market condition. The fair value of employee options is measured on the date of grant and then recognized over the period during which an employee is required to provide services in exchange for the award, known as the requisite service period (usually the vesting period) on a straight-line basis. The Company records expense and an equal adjustment to the liability for stock appreciation units equal to the fair value of the vested portion of the awards as of each period end. Each reporting period thereafter, compensation expense will be recorded based on the remaining service period and the then fair value of the award until vesting of the award is completed. After vesting is completed, the Company will continue to re-measure the fair value of the liability each reporting period until the award is exercised or expires, with changes in the fair value of the liability recorded in the consolidated statements of operations. Restricted stock units are valued at the closing sales price as quoted on the New York Stock Exchange on the date of grant, and are converted into shares of common stock upon vesting on a one-for-one basis. Vesting of restricted stock units is subject to the employee’s continuing service to the Company. The compensation expense related to the restricted stock units is determined using the fair value of common stock on the date of grant, and the expense is recognized on a straight-line basis over the vesting period. Employee stock purchase rights are accounted for at fair value, utilizing the Black-Scholes-Merton option-pricing model. The expense for each purchase period is recognized on a straight-line basis over the requisite service period, from the beginning of the offering period through the respective purchase date. Stock-based compensation expense for modified stock-based awards are recognized using the pool approach, under which the remaining compensation cost from the original awards plus the incremental costs, if any, of the related modified awards is recognized in its entirety over the remaining portion of the requisition service period of the corresponding modified awards. Stock-based compensation expense recognized at fair value includes the impact of estimated forfeitures. The Company estimates future forfeitures at the date of grant and revises the estimates, if necessary, in subsequent periods if actual forfeitures differ from those estimates. Income taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the carrying amounts of existing assets and liabilities in the financial statements and their respective tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rates is recognized in the consolidated statement of operations in the period that includes the enactment date. The Company operates in various tax jurisdictions and is subject to audit by various tax authorities. In preparing the Company’s consolidated financial statements, the Company is required to estimate its taxes in each of the jurisdictions in which it operates. The Company estimates actual current tax exposure as well as assesses temporary differences resulting from different treatment of items, such as accruals and allowances not currently deductible for tax purposes. These differences result in deferred tax assets which represent future tax benefits to be received when certain expenses previously recognized in the financial statements become deductible expenses under applicable income tax laws, or loss credit carryforwards are utilized. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of a deferred tax asset will be realized. 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. A valuation allowance is recorded for loss carryforwards and other deferred tax assets where it is more likely than not that such deferred tax assets will not be realized. In November 2015, the Financial Accounting Standards Board (“FASB”) issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes (“ASU 2015-17”). ASU 2015-17 eliminates the current requirement for organizations to present deferred tax liabilities and assets as current and noncurrent in a classified balance sheet. Instead, organizations will be required to classify all deferred tax assets and liabilities as noncurrent. ASU 2015-17 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2016, with early adoption permitted. The Company early adopted this standard, on a prospective basis, for its financial statements as of and for the year ended December 31, 2015. The Company’s adoption of this standard reduced its prepaid and other current assets and its accrued and other current liabilities while increased its other long-term assets and long term deferred tax liabilities by the corresponding amounts on its consolidated balance sheet as of December 31, 2015. Foreign currency Generally the functional currency of the Company’s international subsidiaries is the local currency. The Company translates the financial statements of these subsidiaries to U.S. dollars using month-end rates of exchange for assets and liabilities, and average rates of exchange for revenue, costs, and expenses. Translation gains and losses are recorded in accumulated other comprehensive (loss) income as a component of stockholders’ equity. Net gains resulting from foreign exchange transactions were $3.4 million, $ 3.1 million, and $0. 9 million for the years ended December 31, 2015, 2014, and 2013, respectively. These gains and losses were recorded as other income, net in the Company’s consolidated statements of operations. Net income (loss) per share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of common shares and potential dilutive common share equivalents outstanding during the period if the effect is dilutive. Recent accounting pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 introduces a lessee model that requires recognition of assets and liabilities arising from qualified leases on the consolidated balance sheets and consolidated statements of operations and to disclose qualitative and quantitative information about lease transactions. This guidance is effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 revises an entity’s accounting related to (1) the classification and measurement of investments in equity securities and (2) the presentation of certain fair value changes for financial liabilities measured at fair value. It also amends certain disclosure requirements associated with the fair value of financial instruments. ASU 2016-01 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2017, with early adoption permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory (“ASU 2015-11”). ASU 2015-11 requires entities to measure most inventory “at the lower of cost and net realizable value” but does not apply to inventories that are measured by using either the last-in, first-out method or the retail inventory method. For the Company, this ASU is effective for annual and interim periods beginning after December 15, 2016. Early adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In May 2014, the FASB issued ASU N o. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual and interim reporting periods beginning after December 15, 2016. Early adoption is not permitted. In August 2015, the FASB issued an accounting standard update for a one-year deferral of the effective date of ASU 2014-09 to annual and interim periods beginning after December 15, 2017 and permits entities to early adopt the standard of ASU 2014-09 for annual and interim reporting periods beginning after December 15, 2016. Companies are permitted to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements.

Cash, cash equivalents and shor

Cash, cash equivalents and short-term investments and restricted cash and investments	12 Months Ended
	Dec. 31, 2015
Restricted Cash and Investment
Cash, cash equivalents and short-term investments and restricted cash and investments	3. Cash, cash equivalents and short-term investments and restricted cash and investments The following table summarizes the Company’s cash, cash equivalents, short-term investments, and restricted cash and investments at December 31, 2015 and 2014 (in thousands): December 31, December 31, 2015 2014 Cash and cash equivalents: Cash $ $ Cash equivalents — Cash and cash equivalents $ $ Short-term investments $ $ — Restricted cash and investments: Restricted cash and investments, current $ $ Restricted cash and investments, non-current — Total restricted cash and investments $ $ The following table summarizes the Company’s unrealized gains and losses related to the cash equivalents, short-term investments and restricted investments in marketable securities designated as available-for-sale (in thousands): As of December 31, 2015 As of December 31, 2014 Gross Gross Gross Gross Amortized Unrealized Unrealized Fair Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cost Gains Losses Value Marketable securities: Money market accounts $ $ — $ — $ $ — $ — $ — $ — Money market funds — — — — Corporate bonds — — Government-sponsored enterprise obligations — — — — — Commercial paper — — — — — — U.S. government securities — — — — — Sovereign government bonds — Variable rate demand notes — — — — — — Total $ $ — $ $ $ $ $ — $ Reported as: Cash equivalents $ $ — $ — $ $ — $ — $ — $ — Short-term investments — — — — — Restricted cash and investments, non-current — — — — — Total $ $ — $ $ $ $ $ — $ As of December 31, 2015 and 2014, maturities of marketable securities were as follows (in thousands): December 31, December 31, 2015 2014 Less than 1 year $ $ Due in 1 to 2 years — Due after 5 years — Total $ $ The Company may sell its investments in the future to fund operating needs and for strategic reasons. As a result, the Company recorded all its marketable securities in short-term investments as of December 31, 2015 and 2014, regardless of the contractual maturity date of the securities. Variable rate demand notes (“VRDNs”) are floating rate municipal bonds with embedded put options that allow the bondholder to sell the security at par plus accrued interest. All of the put options were secured by a pledged liquidity source. Realized gains and losses on the sale of marketable securities during the years ended December 31, 2015, 2014 and 2013 were immaterial. The Company did not recognize any impairment losses on its marketable securities during the years ended December 31, 2015, 2014 or 2013. As of December 31 , 2015, the Company did not have any investments in marketable securities that were in an unrealized loss position for a period in excess of 12 months.

Fair value measurements

Fair value measurements	12 Months Ended
	Dec. 31, 2015
Fair value measurements
Fair value measurements	4. Fair value measurements Assets and Liabilities Measured at Fair Value on a Recurring Basis The following table presents the Company’s assets that are measured at fair value on a recurring basis (in thousands): As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash equivalents, short-term investments and restricted investments: Money market funds $ $ — $ — $ $ $ — $ — $ Money market accounts — — — — — — Corporate bonds — — — — Government-sponsored enterprise obligations — — — — — — Commercial papers — — — — — — U.S. government securities — — — — — — Sovereign government bonds — — — — — — Variable rate demand notes — — — — — — Total $ $ $ — $ $ $ $ — $ Mutual funds held in Rabbi Trust, recorded in other long-term assets $ $ — $ — $ $ $ — $ — $ The Company offers a Non-Qualified Deferred Compensation Plan (“NQDC Plan”) to a select group of its highly compensated employees. The NQDC Plan provides participants the opportunity to defer payment of certain compensation as defined in the NQDC Plan. A Rabbi Trust has been established to fund the NQDC Plan obligation, which was fully funded at December 31, 2015. The assets held by the Rabbi Trust are in the form of exchange traded mutual funds and are included in the Company’s other long-term assets on its consolidated balance sheets at December 31, 2015 and 2014. Level 1 assets are determined by using quoted prices in active markets for identical assets. The fair values of Level 2 assets are priced based on quoted market prices for similar instruments or non-binding market prices that are corroborated by observable market data using inputs such as benchmark yields, broker quotes and other similar data. The following table presents the Company’s liabilities that are measured at fair value on a recurring basis (in thousands): As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Penalty payment derivative (Note 12) $ — $ — $ $ $ — $ — $ $ In 2015, the Company reduced its liabilities related to the penalty payment derivative and recorded a benefit of $0.1 million within other income, net. There were no transfers between levels of the fair value hierarchy during either 2015 or 2014. Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis In 2015, the Company wrote off $0.2 million of property, plant and equipment and $0.2 million of held-for-sale assets recognized and recognized asset impairment charges of $0.4 million within operating expenses (Level 3). In 2014, certain leasehold improvements were written off, resulting in a $1.1 million asset impairment charge within operating expenses (Level 3). These assets were measured at fair value due to events or circumstances the Company identified as having significant impact on their fair value during the respective periods. To arrive at the valuation of these assets, the Company considered the discounted cash flows and categorized the fair value measurement as Level 3 as significant unobservable inputs were used in the valuation. Assets and Liabilities Not Measured at Fair Value The carrying values of cash, restricted cash, accounts receivable, accounts payable, notes payable and short-term borrowings approximate their fair values due to the short-term nature and liquidity of these financial instruments. The fair values of the Company’s long-term debt have been calculated using an estimate of the interest rate the Company would have had to pay on the issuance of liabilities with a similar maturity and discounting the cash flows at that rate which it considers to be a level 2 fair value measurement. The fair values do not necessarily give an indication of the amount that the Company would currently have to pay to extinguish any of this debt. At December 31, 2015 and 2014, the fair value of the Company’s variable rate bank borrowings were not materially different than their carrying value as the interest rates approximated rates currently available to the Company and the fair value of the Company’s acquisition-related debt at December 31, 2014 approximated its carrying value.

Net income (loss) per share

Net income (loss) per share	12 Months Ended
	Dec. 31, 2015
Net income (loss) per share
Net income (loss) per share	5. Net income (loss) per share The following table sets forth the computation of the basic and diluted net income (loss) per share attributable to NeoPhotonics Corporation common stockholders for the periods indicated (in thousands, except per share amounts): Years Ended December 31, 2015 2014 2013 Numerator: Net income (loss) $ $ $ Denominator: Weighted average shares used to compute per share amount: Basic Dilutive effect of equity awards — — Diluted Basic net income (loss) per share $ $ $ Diluted net income (loss) per share $ $ $ The Company has excluded the impact of the following outstanding employee stock options, restricted stock units, common stock warrants and shares expected to be issued under its employee stock purchase plan from the computation of diluted net income (loss) per share, as their effect would have been antidilutive (in thousands): December 31, 2015 2014 2013 Employee stock options Restricted stock units Employee stock purchase plan Common stock warrants — —

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2015
Business Combinations
Business Combinations	6. Business Combinations EMCORE Corporation On January 2, 2015, the Company closed an acquisition of the tunable laser product lines of EMCORE Corporation (“EMCORE”) for an original purchase price of $17.5 million, pursuant to the terms of the Asset Purchase Agreement between the parties dated October 22, 2014, under which the Company purchased certain assets and assumed certain liabilities of EMCORE’s tunable laser product lines . Consideration for the transaction consisted of $1.5 million in cash and a promissory note (the “EMCORE Note”) of approximately $16.0 million, which was subject to certain adjustments for inventory, net accounts receivable and pre-closing revenues, and was subsequently adjusted to $15.5 million in connection with a True-Up Confirmation Agreement (the “True-Up Agreement”) executed by and between the Company and EMCORE on April 16, 2015. The True-Up Agreement made several final adjustments to the Asset Purchase Agreement, including, among other things, (i) adjusting the principal amount of the EMCORE Note from approximately $16.0 million to approximately $15.5 million, (ii) agreeing upon final amounts for inventory value adjustment, net accounts receivable adjustment, and revenue purchase price adjustment, and (iii) resolving the treatment of certain accounts receivable for products sold by EMCORE prior to the closing of the transaction. The adjusted purchase price for the acquisition was approximately $17.0 million. The Company accounted for this acquisition as a business combination. With the acquisition of the EMCORE ultra narrow linewidth tunable laser products , the Company aims to strengthen its portfolio of High Speed Products. In connection with the acquisition, the Company incurred approximately $0.9 million in total acquisition-related costs related to legal, accounting and other professional services. The acquisition costs were expensed as incurred and included in operating expenses in the Company’s consolidated statement of operations. The Company’s allocation of the purchase price to tangible and identifiable intangible assets acquired and liabilities assumed was based on estimated fair values as of the close of the acquisition. The fair values assigned to intangible assets acquired were based on valuations using estimates and assumptions provided by management, with the assistance of an independent third party appraisal firm. The excess purchase price over those fair values was recorded as goodwill. These estimates were determined through established and generally accepted valuation techniques. While the Company uses best estimates and assumptions as part of the purchase price allocation process to value assets acquired and liabilities assumed at the acquisition date, estimates and assumptions are subject to refinement, including the acquired property, plant and equipment, prepaid and other current assets, which primarily consisted of held-for-sale assets, and accounts payable, during the Company’s process of obtaining further information. As a result, during the measurement period which was completed during 2015, the Company recorded adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill. Subsequent to the initial allocation of the assets acquired and liabilities assumed, the Company adjusted the acquired net accounts receivable, the acquired net inventories, the assumed sales tax accrual and the acquired prepaid expenses and other current assets by immaterial amounts, and decreased goodwill by a corresponding net amount. Goodwill recorded consisted of a valuable assembled workforce and market synergy. The amounts assigned to goodwill are deductible for income tax purposes. The following table summarizes the allocation of the assets acquired and liabilities assumed as of the acquisition date and subsequent adjustments (in thousands): Total purchase consideration: Cash paid $ Notes payable Total $ Fair value of assets acquired: Accounts receivable $ Inventories Prepaid expenses and other current assets Property, plant and equipment Intangible assets acquired: Developed technology Customer relationships Total $ Less: fair value of liabilities assumed: Accounts payable $ Accrued liabilities Total $ Goodwill $ Purchased intangibles with finite lives will be amortized on a straight-line basis over their respective estimated useful lives. The following table presents details of the purchase price allocated to the acquired intangible assets at the acquisition date: Useful Purchased Life intangible assets (In years) (In thousands) Developed technology 7 $ Customer relationships 2 Total purchased intangible assets $ The following unaudited supplemental pro forma information presents the combined results of operations of NeoPhotonics Corporation for the years ended December 31, 2015 and 2014 as though the companies had been combined as of the beginning of 2014. In the year ended December 31, 2015, revenue related to products acquired from EMCORE was approximately $55.8 million. The pro forma financial information reflects adjustments related to transactions costs of $0.3 million and $0.6 million in the years ended December 31, 2015 and 2014, respectively, as well as immaterial employee expense in the year ended December 31, 2015. Incremental intangible amortization, inventory and depreciation adjustments were also added to the 2014 period. There were no sales between the business acquired from EMCORE and the Company in the years ended December 31, 2015 or 2014. The unaudited pro forma results do not assume any operating efficiencies as a result of the consolidation of operations (in thousands, except per share data): Year ended December 31, 2015 2014 Revenue $ $ Net income (loss) $ $ Basic net income (loss) per share $ $ Diluted net income (loss) per share $ $ EigenLight Corporation In November 2015 the Company closed an acquisition of the business and products of EigenLight Corporation for cash consideration of $0.4 million in an asset transaction. The Company accounted for this as a business combination and the majority of the purchase price was allocated to inventory and property, plant and equipment. NeoPhotonics Semiconductor On March 29, 2013 the Company acquired certain assets and assumed certain liabilities related to the semiconductor Optical Components Business Unit of LAPIS Semiconductor Co., Ltd., a wholly owned subsidiary of Rohm Co., Ltd (“LAPIS”) of Japan. Total consideration for NeoPhotonics Semiconductor was approximately $ 24.3 million, including cash of $13.1 million and notes payable of $11.1 million. The cash paid included $2.0 million that was withheld and placed into escrow to cover certain indemnity obligations. In October 2014, the Company entered into a settlement agreement covering certain outstanding claims in connection with this acquisition. Under the terms of the settlement agreement, the Company received a payment of $1.0 million (JPY 111.0 million) from the escrow account that was set up under the original merger agreement for disputed excess inventories, which the Company recorded as an escrow settlement gain in 2014. In connection with the acquisition, the Company incurred approximately $5.4 million in acquisition-related costs related to investment banking, legal, accounting and other professional services and transfer taxes related to real property acquired. The acquisition costs were expensed as incurred and are included in operating expenses in the Company’s 2013 consolidated statement of operations. The Company accounted for its acquisition of the NeoPhotonics Semiconductor assets and assumed liabilities as a business combination. NeoPhotonics Semiconductor’s tangible and identifiable intangible assets acquired and liabilities assumed were recorded based upon their estimated fair values as of the closing date of the acquisition. The estimated fair values of the identifiable assets acquired and liabilities assumed approximated the purchase price; therefore, no goodwill was recorded. The following table summarizes the acquisition accounting and the tangible and intangible assets acquired as of the date of acquisition and subsequent adjustments (in thousands): Total purchase consideration: Cash paid $ Notes payable $ Liabilities assumed: Pension and retirement obligations $ Other compensation-related liabilities Other current liabilities $ Fair value of assets acquired: Inventory $ Other current assets Land, property, plant and equipment Intangible assets acquired: Developed technology Customer relationships $ The approach for measuring the fair value of the assets acquired and liabilities assumed is described below: Net Tangible Assets NeoPhotonics Semiconductor’s tangible assets acquired and liabilities assumed as of March 29, 2013 were recorded at estimated fair value. The Company estimated fair value by adjusting NeoPhotonics Semiconductor’s historical value of property, plant and equipment to an estimate of depreciated replacement cost, adjusted for economic obsolescence. The Company depreciates property, plant and equipment over estimated lives of 2 to 20 years, and records the expense to cost of goods sold and operating expense. The fair value of inventory acquired was determined using a net realizable value approach based upon the expected sales value of the inventory, less any costs to complete and selling costs along with a reasonable profit margin based on historical and expected results. Intangible Assets Developed technology represents products that have reached technological feasibility. NeoPhotonics Semiconductor’s current product offerings include high speed semiconductor and high speed laser and photodetector devices for communication networks. The fair value of developed technology intangibles acquired was determined by using a royalty-avoidance method. The share of future revenue relating to current technology was forecasted, using an estimate for obsolescence such that the share declines over time. A royalty rate of two percent was used to calculate royalty savings on that revenue that are avoided since the Company owns the technology and does not need to license it from other parties. The after-tax royalty savings was then discounted to present value using the Company’s discount rate. The Company amortizes the developed technology intangible assets over estimated lives of 4 to 5 years, and amortization expense is recorded to cost of goods sold. The customer relationships asset represents the value of the ability to sell existing, in-process, and future versions of the technology to the NeoPhotonics Semiconductor existing customer base. The Company utilized the excess earnings method, estimating future cash flows that will result from existing customers given assumed retention rates, and then discounting those flows to their present value using the Company’s discount rate. The Company amortizes the customer relationships intangible asset over an average estimated life of 6 years, and amortization expense is recorded to operating expenses. The following unaudited supplemental pro forma information presents the combined results of operations of NeoPhotonics Corporation and NeoPhotonics Semiconductor for the years presented as if the NeoPhotonics Semiconductor acquisition had been completed at the beginning of 2012. The pro forma financial information includes adjustments related to one time charges, amortization of fair value adjustments and elimination of NeoPhotonics Semiconductor’s revenues and cost of goods sold from its sales to the Company prior to the acquisition. As a result of the elimination adjustments, revenues were reduced by $1.9 million and cost of goods sold was reduced by $1.8 million for 2013. The pro forma financial information for 2013 also included elimination of $5.4 million in transaction costs and a decrease in cost of goods sold of $3.2 million due to a change in the value of inventory as a result of acquisition accounting. I ncremental intangible amortization, inventory and depreciation adjustments of $0.3 million, net of tax impact, were added to the 2015 period for assets that would have been fully amortized. The following unaudited pro forma results for the years ended December 31, 2015, 2014 and 2013 do not assume any operating efficiencies as a result of the consolidation of operations (in thousands, except per share data): 2015 2014 2013 Revenue $ $ $ Net income (loss) $ $ ) $ ) Basic net income (loss) per share $ $ ) $ ) Diluted net income (loss) per share $ $ ) $ ) The unaudited pro forma financial information is presented for informational purposes only and is not indicative of the results of operations that would have been achieved had the acquisition taken place as of January 1, 2012, nor does it intend to be a projection of future results.

Purchased intangible assets

Purchased intangible assets	12 Months Ended
	Dec. 31, 2015
Purchased intangible assets
Purchased intangible assets	7. Purchased intangible assets Purchased intangible assets consist of the following (in thousands): December 31, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Assets Amortization Assets Assets Amortization Assets Technology and patents $ $ $ $ $ $ Customer relationships Leasehold interest Supplier relationships and other — — — — $ $ $ $ $ $ Amortization expense relating to technology and patents and the leasehold interest intangible assets is included within cost of goods sold, and customer relationships and the non-compete agreements within operating expenses. The following table presents details of the amortization expense of the Company’s purchased intangible assets as reported in the consolidated statements of operations (in thousands): Years ended December 31, 2015 2014 2013 Cost of goods sold $ $ $ Operating expenses Total $ $ $ The estimated future amortization expense of purchased intangible assets as of December 31, 2015, is as follows (in thousands): 2016 $ 2017 2018 2019 2020 Thereafter $

Balance sheet components

Balance sheet components	12 Months Ended
	Dec. 31, 2015
Balance Sheet Components [Abstract]
Balance sheet components	8. Balance sheet components Restricted Cash and Investments Restricted cash and investments were as follows (See Note 10) (in thousands): December 31, 2015 2014 Restricted in connection with notes payable $ $ Restricted in connection with Comerica Bank term loan — Total restricted cash and investments $ $ Reported as: Restricted cash and investments $ $ Restricted cash and investments, non-current — Total restricted cash and investments $ $ Accounts receivable, net Accounts receivable, net were as follows (in thousands): December 31, 2015 2014 Accounts receivable $ $ Trade notes receivable Allowance for doubtful accounts $ $ The table below summarizes the movement in the Company’s allowance for doubtful accounts (in thousands): Balance at December 31, 2012 $ Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2013 Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2014 Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2015 $ Inventories Inventories were as follows (in thousands): December 31, 2015 2014 Raw materials $ $ Work in process Finished goods $ $ Included in finished goods was $14.2 million and $6.4 million of inventory at customer vendor managed inventory locations at December 31, 2015 and 2014, respectively. Property, plant and equipment, net Property, plant and equipment, net were as follows (in thousands): December 31, 2015 2014 Land $ $ Buildings Machinery and equipment Furniture, fixtures, software and office equipment Leasehold improvements Less: Accumulated depreciation $ $ Depreciation expense was $17.7 million $19.1 million and $16.3 million for the years ended December 31, 2015, 2014 and 2013, respectively. In 2014, the Company wrote off certain leasehold improvements in its facility in Fremont, California and recorded an asset impairment charge of $1.1 million in connection with the Company’s business re-alignment initiatives. Accrued and other current liabilities Accrued and other current liabilities were as follows (in thousands): December 31, 2015 2014 Employee-related $ $ Income and other taxes payable Accrued warranty Penalty payment derivative Deferred income tax liabilities — Other accrued expenses $ $ Accrued warranty The table below summarizes the movement in the warranty accrual, which is included in accrued and other current liabilities (in thousands): Years ended December 31, 2015 2014 2013 Beginning balance $ $ $ Warranty accruals Assumed warranty from acquisitions — — Settlements Ending balance $ $ $ Other noncurrent liabilities Other noncurrent liabilities were as follows (in thousands): December 31, 2015 2014 Pension and other employee-related $ $ Other $ $

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2015
Restructuring
Restructuring	9. Restructuring In 2014, the Company initiated a restructuring plan (the “2014 Restructuring Plan”) to refocus on its strategy execution, optimize its structure, and improve operational efficiencies. The 2014 Restructuring Plan consisted of workforce reductions primarily in the U.S and in China. The Company recorded $0.2 million and $1.1 million in restructuring charges related to the 2014 Restructuring Plan in 2015 and 2014, respectively, which were included within cost of goods sold and operating expenses. During 2013, the Company exited and closed one facility at its headquarters location to align its facilities usage with its current size. Additionally, the Company approved and implemented a restructuring action to reduce its workforce and close a facility in China and to exit its contract manufacturing activities in Malaysia. The Company recorded a restructuring charge of $1.5 million during 2013 related to these actions, of which $0.8 million was recorded in operating expenses with the remainder recorded in cost of goods sold. The balance related to facilities was fully paid at December 31, 2015. The following table summarizes the activit ies associated with the restructuring plans during the years ended December 31, 2015, 2014 and 2013 (in thousands): Workforce Contract Reduction Facilities Termination Total Restructuring obligations, December 31, 2012 $ — $ — $ — $ — Restructuring costs incurred Cash payments Non-cash settlements and other — — Restructuring obligations, December 31, 2013 — Restructuring costs incurred — — Cash payments Restructuring obligations, December 31, 2014 — Restructuring costs incurred — — Cash payments — Restructuring obligations, December 31, 2015 $ — $ — $ — $ —

Debt

Debt	12 Months Ended
	Dec. 31, 2015
Debt
Debt	10. Debt The table below summarizes the carrying amount and weighted average interest rate of the Company’s notes payable and long-term debt (in thousands, except percentages): December 31, 2015 December 31, 2014 Weighted Weighted Average Average Carrying Interest Carrying Interest Amount Rate Amount Rate Notes payable $ — $ — Bank borrowings-Comerica Bank % — — Short-term borrowing — — % Total notes payable and short-term borrowing $ $ Long-term debt, current and non-current: Bank borrowings-Comerica Bank $ — — $ % Bank borrowings-Mitsubishi Bank % — — Acquisition-related debt — — % Total long-term debt, current and non-current Unaccreted discount within current portion of long-term debt — Unaccreted discount within long-term debt, net of current portion — Total long-term debt, net of unaccreted discount $ $ Reported as: Current portion of long-term debt $ $ Long-term debt, net of current portion Total long-term debt, net of unaccreted discount $ $ Notes payable The Company regularly issues notes payable to its suppliers in China in exchange for accounts payable. These notes are supported by noninterest bearing bank acceptance drafts issued under the Company’s existing line of credit facility and are due three to six months after issuance. As a condition of the notes payable arrangements, the Company is required to keep a compensating balance at the issuing banks that is a percentage of the total notes payable balance until the amounts are settled. At December 31, 2015, the Company’s subsidiary in China had two short-term line of credit facilities with banking institutions. Under the first agreement, which has been renewed to expire in June 2016 , RMB 120.0 million ( $18.5 million) can be used for short-term loans, which will bear interest at varying rates or up to RMB 171.4 million ( $26.4 million) can be used for bank acceptance drafts (with a 30% compensating balance requirement). Under the second agreement, which has been renewed to expire in September 2016 , RMB 133.0 million ( $20.5 million) can be used for short-term loans or up to approximately RMB 190.0 million ( $29.3 million) can be used for bank acceptance drafts (with a 30% compensating balance requirement). As of December 31, 2015 and 2014, the non-interest bearing bank acceptance drafts issued in connection with the Company’s notes payable to its suppliers in China under these line of credit facilities had an outstanding balance of $8.9 million and $12.8 million, respectively. As of December 31, 2015 and 2014, compensating balances relating to these credit facilities totaled $2.7 million and $3.8 million, respectively. Compensating balances are classified as restricted cash and investments on the Company’s consolidated balance sheets. Acquisition-related As part of the purchase consideration to acquire the tunable laser products of EMCORE in January 2015 (See Note 6), the Company issued the EMCORE Note, as amended, of $15.5 million, which had a maturity of two years from the closing of the transaction and an interest rate of 5% per annum for the first year and 13% per annum for the second year. The interest was payable semi-annually in cash. In addition, the EMCORE Note was subject to prepayment under certain circumstances and was secured by certain of the assets to be sold pursuant to the asset purchase agreement with EMCORE. The EMCORE Note was subordinated to the Company’s existing bank debt in the U.S. The EMCORE Note, as amended, was repaid in full in April 2015. In connection with the acquisition of NeoPhotonics Semiconductor on March 29, 2013, the Company was obligated to pay 1,050 million Japanese Yen (the “JPY”) in three equal installments on the anniversaries of the closing date for the purchase of the real estate used by NeoPhotonics Semiconductor of which 700 million JPY( $5.8 million) was outstanding at December 31, 2014. The obligation bore interest at 1.5% per year, payable annually, and was secured by the acquired real estate property. This loan was repaid in full in February 2015. Bank borrowings In April 2015, the Company’s subsidiary in China executed a $5.0 million advance financing agreement under one of its credit line facilities at an interest rate based on a six -month LIBOR plus 330 basis points , or approximately 3.71% . Both interest and principal were due and repaid in full in 2015. At December 31, 2014, the Company’s subsidiary in China had $10 .0 million outstanding under two short-term advance financing agreements under its line of credit facilities. The borrowings were made against export sales to its parent company and bore interest and other fees at rates ranging from 2.33% to 4.02% per annum. Interest and principal were due and repaid in full in 2015 . The Company has a credit agreement with Comerica Bank as lead bank in the U.S. In January 2015, the Company executed an amendment to its credit agreement with Comerica Bank to refinance the then-outstanding Comerica term loan. Under the Credit Amendment, the $20.0 million revolving credit facility was replaced with a $25.0 million senior secured revolving credit line with a maturity date on November 2, 2016. In March 2015, the senior secured revolving credit line was further amended to increase the borrowing capacity from $25.0 million to $30.0 million. Borrowings under the amended revolving credit facility bear interest at an interest rate option of a base rate as defined in the agreement plus 1.75% or LIBOR plus 2.75% . The base rate is the greater of (a) the effective prime rate, (b) the Federal Funds effective rate plus one percent, and (c) the daily adjusting LIBOR rate plus one percent. The Credit Amendment also modified the EBITDA and liquidity covenants and eliminated the need to maintain compensating balances (restricted cash). The credit agreement also restricts the Company’s ability to incur certain additional debt or to engage in specified transactions, restricts the payment of dividends to its stockholders in the event of a default and is secured by substantially all of the Company’s U.S. assets, other than intellectual property assets. The components of the Comerica credit facilities are as follows: · A $30.0 million revolving credit facility subject to covenant requirements, under which there was $23.8 million outstanding at December 31 , 2015 which was repaid in full in January 2016. There was no outstanding borrowing as of December 31, 2014. Amounts borrowed are due on or before November 2, 2016 and bear interest at an interest rate option of a base rate as defined in the agreement plus 1.75% or LIBOR plus 2.75% . As of December 31 , 2015 the rate on the LIBOR option was 2.99% . · Under the term loan facility, $17.5 million was outstanding at December 31, 2014 which was repaid in full in January 2015. Prior to the repayment, borrowings under the term loan bore interest at an interest rate option of a base rate as defined in the agreement plus 2.0% or LIBOR plus 3.0% . The Company’s original credit agreement with Comerica Bank required the maintenance of specified financial covenants, including a debt to EBITDA ratio and liquidity ratios. The Company was not in compliance with the debt to EBITDA covenant at December 31, 2014, which noncompliance was effectively waived in an amendment to the credit agreement the Company executed, during 2014, that waived the testing of certain covenants for compliance, provided that the Company maintained compensating balances equal to outstanding amounts under the credit agreement in accounts for which the bank had sole access. The Company’s amended credit agreement with Comerica executed in January 2015 modified the financial covenants to replace the compensating balance requirement with the maintenance of at least half of the projected EBITDA and a minimum liquidity ratio of 1.5 to 1.0. The Company was in compliance with the modified covenants as of December 31, 2015 and expects to be in compliance for the next 12 months. As of December 31 , 2015 and 2014, the amount of the Company’s cash and investments in its compensating balance accounts for the term loan facility with Comerica Bank was zero and $17.5 million, respectively, which was classified as current and non-current restricted cash and investments on the Company’s consolidated balance sheet. On February 25, 2015, the Company entered into certain loan agreements and related special agreements (collectively, the “Loan Arrangements”) with the Bank of Tokyo-Mitsubishi UFJ, Ltd. (the “Mitsubishi Bank”) that provided for (i) a term loan in the aggregate principal amount of 500 million JPY ( $4.2 million) (the “Term Loan A”) and (ii) a term loan in the aggregate principal amount of one billion JPY ( $8.4 million) (the “Term Loan B” and together with the Term Loan A, the “Mitsubishi Bank Loans”). The Mitsubishi Bank Loans are secured by a mortgage on certain real property and buildings owned by our Japanese subsidiary. The full amount of each of the Mitsubishi Bank Loans was drawn on the closing date of February 25, 2015. Interest on the Mitsubishi Bank Loans accrues and is paid monthly based upon the annual rate of the monthly Tokyo Interbank Offer Rate (TIBOR) plus 1.40% . The Term Loan A requires interest only payments until the maturity date of February 23, 2018 , with a lump sum payment of the aggregate principal amount on the maturity date. The Term Loan B requires equal monthly payments of principal equal to 8,333,000 JPY until the maturity date of February 25, 2025, with a lump sum payment of the balance of 8,373,000 JPY on the maturity date. Interest on the Term Loan B is accrued based upon monthly TIBOR plus 1.40% and is secured by real estate collateral. In conjunction with the execution of the Bank Loans, the Company paid a loan structuring fee, including consumption tax, of 40,500,000 JPY ( $0.3 million) . The Mitsubishi Bank Loans contain customary representations and warranties and customary affirmative and negative covenants applicable to the Company’s Japanese subsidiary, including, among other things, restrictions on cessation in business, management, mergers or acquisitions. The Mitsubishi Bank Loans contain financial covenants relating to minimum net assets, maximum ordinary loss and a dividends covenant. The Mitsubishi Bank Loans also include customary events of default, including but not limited to the nonpayment of principal or interest, violations of covenants, restraint on business, dissolution, bankruptcy, attachment and misrepresentations. In February 2015, the Company used a portion of the proceeds of the Mitsubishi Bank Loans to repay the then-outstanding loan related to the acquisition of NeoPhotonics Semiconductor, which had an outstanding principal and interest amount of approximately 710 million JPY ( $6.0 million) and the remainder will be used for general working capital. As of December 31 , 2015, the outstanding principal balance under the Mitsubishi Bank Loans was approximately 1.4 billion JPY (approximately $11.8 million) and the Company was in compliance with the related covenants. At December 31, 2015, maturities of long-term debt were as follows (in thousands): 2016 $ 2017 2018 2019 2020 Thereafter $

Pension Plans

Pension Plans	12 Months Ended
	Dec. 31, 2015
Pension Plans
Pension Plans	11. Pension Plans Japan defined benefit pension plans In connection with its acquisition of NeoPhotonics Semiconductor in 2013, the Company assumed responsibility for two defined benefit plans that provide retirement benefits to its NeoPhotonics Semiconductor employees in Japan: the Retirement Allowance Plan (“RAP”) and the Defined Benefit Corporate Pension Plan (“DBCPP”). The RAP is an unfunded plan administered by the Company. Effective February 28, 2014, the DBCPP was converted to a defined contribution plan (“DCP”). In May 2014, LAPIS transferred approximately $2.0 million into the newly formed DCP which was the allowable amount that can be transferred according to the Japanese regulations. LAPIS also paid the Company approximately $0.3 million in connection with the conversion of the plan. Additionally, the Company transferred the net unfunded projected benefit obligation amount from the DBCPP to the RAP and froze the RAP benefit at the February 28, 2014 amount. Under the RAP, lump sum benefits are provided upon retirement or upon certain instances of termination. In 2014, the Company reclassified $0.2 million and $0.1 million from accumulated other comprehensive income to cost of goods sold and operating expenses, respectively. The funded status of these plans for the years ended December 31, 2015 and 2014 was as follows (in thousands): 2015 2014 RAP RAP DBCPP Change in projected benefit obligation: Projected benefit obligation, beginning of period $ $ $ Service cost — Interest cost Benefits paid — Actuarial (gain)/loss Curtailment/Settlement — Transfer from DBCPP to RAP — Currency translation adjustment Projected benefit obligation, end of period $ $ $ — Change in plan assets: Plan assets at fair value, beginning of period $ — $ — $ Employer contributions — — Benefits paid — — Actual return on plan assets — — — Transfer to DCP — — Currency translation adjustment — — Plan assets at calculated amount, end of period $ — $ — $ — Amounts recognized in consolidated balance sheets: Accrued and other current liabilities $ $ $ — Other noncurrent liabilities $ $ $ — Amount recognized in accumulated other comprehensive loss: Defined benefit pension plans adjustment $ $ $ — Accumulated benefit obligation, end of period $ $ $ — Net periodic pension cost associated with these plans for the years ended December 31, 2015 and 2014 and the period from March 29, 2013 to December 31, 2013 included the following components (in thousands): Year ended December 31, Year ended December 31, Period from March 28, 2013 2015 2014 to December 31, 2013 RAP RAP DBCPP RAP DBCPP Service cost $ — $ $ $ $ Interest cost Expected return on plan assets — — — — Other — — — — Curtailment/settlement (gain) loss — — — Net periodic pension (gain) costs $ $ $ $ $ The projected and accumulated benefit obligations for the RAP were calculated as of December 31, 2015 and 2014 using a discount rate assumption of 0.2% and 0.2% , respectively. Estimated future benefit payments under the RAP are as follows (in thousands): 2016 $ 2017 2018 2019 2020 2021 - 2025 Thereafter $ 401(k) Plan The Company maintains a savings and retirement plan qualified under Section 401(k) of the Internal Revenue Code of 1986, as amended (the "IRC"). Employees meeting the eligibility requirements, as defined under the IRC, may contribute up to the statutory limits each year. The Company currently matches a portion of all eligible employee contributions which vest immediately. The Company’s matching contributions to the plan totaled $0.3 million for each of the years ended December 31, 2015, 2014, and 2013.

Commitments and contingencies

Commitments and contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and contingencies	12. Commitments and contingencies Leases The Company leases various facilities under non-cancelable operating leases. As of December 31, 2015, the future minimum commitments under the Company’s non-cancelable operating leases are as follows (in thousands): Years ending December 31, 2016 $ 2017 2018 2019 2020 Thereafter $ The total minimum lease commitment amount above does not include minimum sublease rent income of $1.4 million receivable in the future under non-cancelable sublease agreements. The Company recognizes rent expense on a straight-line basis over the lease period. Rent expense under the Company’s operating leases was $2.2 million in each of the years ended December 31, 2015, 2014, and 2013. Litigation From time to time, the Company is subject to various claims and legal proceedings, either asserted or unasserted, that arise in the ordinary course of business. The Company accrues for legal contingencies if the Company can estimate the potential liability and if the Company believes it is probable that the case will be ruled against it. If a legal claim for which the Company did not accrue is resolved against it, the Company would record the expense in the period in which the ruling was made. The Company believes that the likelihood of an ultimate amount of liability, if any, for any pending claims of any type (alone or combined) that will materially affect the Company’s financial position, results of operations or cash flows is remote. The ultimate outcome of any litigation is uncertain, however, and unfavorable outcomes could have a material negative impact on the Company’s financial condition and operating results. Regardless of outcome, litigation can have an adverse impact on the Company because of defense costs, negative publicity, diversion of management resources and other factors. On January 5, 2010, Finisar Corporation, or Finisar, filed a complaint in the U.S. District Court for the Northern District of California against Source Photonics, Inc., MRV Communications, Inc., Oplink Communications, Inc. and the Company, or collectively, the co-defendants. In the complaint Finisar alleged infringement of certain of its U.S. patents. In 2010 the Company filed an answer to the complaint and counterclaims, asserting two claims of patent infringement and additional claims. The court dismissed without prejudice all co-defendants (including the Company) except Source Photonics, Inc., on grounds that such claims should have been asserted in four separate lawsuits, one against each defendant. This dismissal does not prevent Finisar from bringing a new similar lawsuit against the Company. In 2011 the Company and Finisar agreed to suspend their respective claims and in 2012 they further agreed to toll their respective claims. While there has been no action on this matter since 2012, the Company is currently unable to predict the outcome of this dispute and therefore cannot determine the likelihood of loss nor estimate a range of possible loss. On January 2, 2013, the Company was served with a lawsuit, filed in Belgium by a distributor called Laser 2000 Beneluo SA (“Laser 2000”) claiming unpaid commissions. The distributor agreement was formally terminated as of January 3, 2012. The Company paid $492,000 to Laser 2000 as partial settlement of claims and to avoid penalties from the Court and submitted a legal brief to court on September 16, 2013. Laser 2000 filed a response on December 16, 2013 and the Company filed the final rebuttal brief on January 30, 2014. On March 23, 2015, the Belgian Court issued a ruling awarding Laser 2000 approximately one million euros in damages (approximately $1,100,000 at current exchange rates). The Company was served with the judgment on September 28, 2015. The Company filed an appeal to the verdict in December 2015, but is unable to predict the duration or outcome of the appeal or the overall lawsuit at this time. The Company does not believe it will ultimately be liable for the full amount of damage; however, in light of developments in the case, the Company increased its accrual for estimated probable litigation expense relating to this matter in March 2015. Indemnifications In the normal course of business, the Company enters into agreements that contain a variety of representations and warranties and provide for general indemnification. The Company’s exposure under these agreements is unknown because it involves claims that may be made against the Company in the future, but have not yet been made. To date, the Company has not paid any claims or been required to defend any action related to its indemnification obligations. However, the Company may record charges in the future as a result of these indemnification obligations. As of December 31, 2015, the Company does not have any material indemnification claims that were probable or reasonably possible. Purchase obligations The Company has open purchase orders with its suppliers for the purchase of inventory and other items in the ordinary course of its business. As of December 31, 2015, the Company’s estimate of outstanding amounts under these purchase orders was approximately $34.8 million, primarily expected to be purchased within the next 12 months. Certain of these open purchase orders may be cancellable without penalty. Penalty Payment Derivative In connection with a private placement transaction in 2012, the Company agreed to certain performance obligations including establishing a wholly-owned subsidiary in Russia and making a $30.0 million investment commitment (the ‘Investment Commitment’) towards the Company’s Russian operations, which could be partially satisfied by cash and/or non-cash investment inside or outside of Russia and/or by way of non-cash asset transfers. In March 2015, the Company extended the Investment Commitment deadline from March 31, 2015 to June 30, 2015 and then further amended the Investment Commitment in July 2015. The latter amendment became effective on June 30, 2015 and provides that the maximum amount of penalties (the ‘Penalty Payment’) to be paid by the Company will not exceed $5.0 million in the aggregate. In addition, the amendment also provides for an updated investment plan for the Company’s Russian subsidiaries that includes non-cash transfer of licensing rights to intellectual property, non-cash transfers of existing equipment and commitments to complete the remaining investment milestones through fiscal year 2019. If the Company’s cumulative investment and spending to its Russian subsidiaries is less than $18.8 million by December 31, 2016, the Company will be subject to a $1.5 million penalty within 30 days after the end of a 90 -day cure period. If certain of the Investment Commitments are achieved in the indicated time frames in 2016 and 2019, the Company also has the ability to cease the operations of its Russian subsidiaries by paying exit fees of $3.5 million or $2.0 million at the end of 2016 or 2019, respectively . The Company fulfilled the investment commitment required by the end of 2015 and has contributed over $15.4 million in cash and assets to its Russian subsidiaries as of December 31, 2015. The purchaser of the common stock has non-transferable veto rights over the Company’s Russian subsidiaries’ annual budget during the investment period and must approve non-cash asset transfers to be made in satisfaction of the Investment Commitment. Spending and/or commitments to spend for general working capital and research and development do not require approval by the purchaser. There are no legal restrictions on the specific usage of the $39.8 million received in the private placement transaction or on withdrawal from the Company’s bank accounts for use in general corporate purposes. The Company has accounted for the $5.0 million Penalty Payment as an embedded derivative instrument (the “Penalty Payment Derivative”), with the underlying being the performance or nonperformance of meeting the Investment Commitment and initially classified $4.9 million of the $5.0 million as additional paid-in capital and the remaining $0.1 million, representing the estimated fair value of the Penalty Payment derivative, in other noncurrent liabilities. The fair value of the Penalty Payment Derivative has been estimated at the date of the original common stock sale (April 27, 2012) and at each subsequent balance sheet date using a probability-weighted discounted future cash flow approach using unobservable inputs, which are classified as Level 3 within the fair value hierarchy. The primary inputs for this approach include the probability of achieving the Investment Commitment and a discount rate that approximates the Company’s incremental borrowing rate. After the initial measurement, changes in the fair value of this derivative were recorded in other income, net. The estimated fair value of this derivative was $ 0.4 million and $0.5 million as of December 31, 2015 and December 31, 2014, respectively. Separately, in December 2014, the Company entered into a Commitment to File a Registration Statement and Related Waiver of Registration Rights, whereby Joint Stock Company “RUSNANO” (formerly Open Joint Stock Company “RUSNANO"), or Rusnano, waived certain registration rights in connection with a potential offering by the Company of shares of the Company’s common stock, and the Company committed to file with the U.S. Securities and Exchange Commission a resale registration statement on Form S-1 covering the resale of all shares of the Company’s common stock held by Rusnano. The Company filed such resale registration statement in April 2015 (See Note 13). Rusnano also waived its demand registration rights under the original rights agreement and agreed to enter into a lock up agreement with the Company whereby it would agree not to sell any shares of the Company’s common stock, or engage in certain other transactions relating to the Company’s securities, for a period of 60 days from the filing date of the resale registration statement. Rusnano signed such lock up agreement with the Company on April 2, 2015. In addition, in connection with the Company’s public stock offering completed in the second quarter of 2015 (see Note 13), Rusnano entered into a separate lock up agreement with Needham & Company, LLC, the lead underwriter of the offering, whereby it agreed not to sell any shares of the Company’s common stock, or engage in certain other transactions relating to the Company’s securities. The lock-up agreement expired 180 days after May 21, 2015. Escrow Settlement with Santur In May 2014, the Company entered into an escrow settlement agreement covering the outstanding claims in connection with its 2011 acquisition of Santur Corporation (“Santur”). Under the terms of the escrow settlement agreement, a net amount of $1.9 million was paid to the Company from the escrow account that was set up under the original merger agreement. This amount comprised a $3.9 million gain related to indemnification claims by the Company (“Indemnification Amount”) which was partially offset by $2.0 million in additional consideration to Santur that was contingent upon Santur’s gross profit performance during 2012 (“Contingent Consideration Amount”). The Company had recorded the entire $2.0 million Contingent Consideration Amount as of December 31, 2013 . The $3.9 million Indemnification Amount was recognized as settlement gain in 2014.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Stockholders’ Equity
Stockholders’ Equity	13. Stockholders’ Equity Common stock As of December 31, 2015, the Company had reserved 6,926,534 shares of common stock for issuance under its stock option plans and 378,503 shares of common stock for issuance under its stock purchase plan. Resale Registration Statement In April 2015, the Company filed a resale registration statement, which registered 4,972,905 shares of the Company’s common stock, at a par value of $0.0025 per share, held by Rusnano. The Company does not receive any proceeds from any sales of the Company’s common stock held by Rusnano (See Note 12). Follow-On Public Offering In the second quarter of 2015, the Company completed a follow-on offering, in which the Company sold 6,866,689 shares of its common stock, including 895,655 shares of common stock sold upon the exercise in full of the overallotment option by the underwriters, at a public offering price of $7.25 per share. The Company raised approximately $45.6 million , net of underwriting discounts of $3.0 million and other offering expenses of approximately $1.2 million . Accumulated Other Comprehensive (Loss) Income The following table shows the components of accumulated other comprehensive (loss) income, net of taxes, as of December 31, 2015, 2014 and 2013 (in thousands): 2015 2014 2013 Foreign currency translation adjustments $ $ $ Unrealized gains on available-for-sale securities Defined benefit pension plan adjustment $ $ $ No material amounts were reclassified out of accumulated other comprehensive income during the years ended December 31, 2015, 2014 or 2013. Accumulated Deficit Approximately $ 7.9 million and $7.1 million of the Company’s retained earnings within its accumulated deficit at December 31, 2015 and 2014, respectively, was subject to restriction due to a requirement that its subsidiaries in China set aside at least 10% of their respective accumulated profits each year to fund statutory common reserves as well as allocate a discretional portion of their after-tax profits to their staff welfare and bonus fund.

Stock-based compensation

Stock-based compensation	12 Months Ended
	Dec. 31, 2015
Stock-based compensation
Stock-based compensation	14. Stock-based compensation Equity incentive programs 2004 Stock Option Plan In March 2004, the Company adopted the 2004 Stock Option Plan (the “2004 Plan”) for the benefit of its eligible employees, consultants and independent directors. In February 2011, in connection with the closing of the Company’s initial public offering and execution of the associated underwriting agreement, shares authorized for issuance under the 2004 Plan were cancelled (except for those shares reserved for issuance upon exercise of outstanding stock options). As of December 31, 2015, options to purchase 1,131,570 shares were outstanding under the 2004 Plan and no shares were available for future grant. 2007 Stock Appreciation Grants Plan In October 2007, the Company adopted its 2007 Stock Appreciation Grants Plan (the “2007 Plan”). The 2007 Plan provides for the grant of units (“stock appreciation units”) entitling the holder upon exercise to receive cash in an amount equal to the amount by which the Company’s common stock has appreciated in value. Each stock appreciation unit entitles a participant to a cash payment in the amount of the excess of the fair market value of a share of common stock on the exercise date over the fair market value of a share of common stock on the award date. The total appreciation available to a participant from the exercise of an award is equal to the number of stock appreciation units being exercised, multiplied by the amount of appreciation per stock appreciation unit. The stock appreciation units granted under the 2007 Plan were primarily granted to employees or consultants of the Company’s subsidiaries in China. The Company re-measures the fair value (based on the market price of the Company’s common stock at the relevant period end) of all vested and outstanding stock appreciation units and adjusts compensation expense and corresponding liability accordingly. The Company also recognizes compensation expense for additional vested stock appreciation units. As of December 31, 2015, 342,316 stock appreciation units were outstanding, of which 17,142 stock appreciation units were vested. The Company does not intend to grant additional stock appreciation units under the 2007 Plan. 2010 Equity Incentive Plan In April 2010, the Company adopted its 2010 Equity Incentive Plan (the “2010 Plan”). The 2010 Plan will terminate on April 13, 2020, unless sooner terminated by the board of directors. The 2010 Plan provides for the grant of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, market-based stock awards, and other forms of equity compensation, or collectively, stock awards, all of which may be granted to employees, including officers, and to non-employee directors and consultants. Additionally, the 2010 Plan provides for the grant of market-based cash awards. Incentive stock options may be granted only to employees. All other awards may be granted to employees, including officers, and to non-employee directors and consultants. Under the terms of the 2010 Plan, awards may be granted at prices not less than 100% of the fair value of the Company’s common stock, as determined by the Company’s board of directors, on the date of grant for an incentive stock option and not less than 85% of the fair value of the Company’s common stock on the date of grant for a non-qualified stock option. Options vest over a period of time as determined by the board of directors, generally over a three to four year period, and expire ten years from date of grant. Initially, the aggregate number of shares of the Company’s common stock that may be issued pursuant to stock awards under the 2010 Plan was 865,420 shares. The number of shares of the Company’s common stock reserved for issuance under the 2010 Plan automatically increase on January 1st each year, starting on January 1, 2012 and continuing through January 1, 2020, by 3.5% of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year, or such lesser number of shares of common stock as determined by the Company’s board of directors. The maximum number of shares that may be issued pursuant to the exercise of incentive stock options under the 2010 Plan is 8,000,000 shares. As of December 31, 2015, stock options to purchase and restricted stock units to convert to a total of 3,480,080 shares of common stock were outstanding under the 2010 Plan and 323,493 shares were reserved for future issuance. 2010 Employee Stock Purchase Plan In February 2011, the Company adopted its 2010 Employee Stock Purchase Plan (the “2010 ESPP”). The 2010 ESPP was implemented through a series of offerings of purchase rights to eligible U.S. employees. The offering period is for 12 months beginning November 16 th of each year, with two purchase dates on May 15 th and November 15 th . Due to the delay in filing its 2013 Annual Report on Form 10-K, in May 2014 the Compensation Committee of the Company’s Board of Directors (the “Committee”) rescheduled the May 15 purchase date under the then offering period to June 17, 2014. Additionally, the Committee waived the existing purchase limits for the June 17, 2014 purchase only and created a modification of the purchase price formula for such offering period. In connection with this modification, the Company recorded an immaterial charge as stock based compensation expense in its 2014 consolidated statements of operations. The 2010 ESPP initially authorized the issuance of 342,568 shares of the Company’s common stock pursuant to purchase rights granted to employees or to employees of designated affiliates. The number of shares of common stock reserved for issuance automatically increase on January 1st of each year, starting January 1, 2012 and continuing through January 1, 2020, in an amount equal to the lesser of (1) 3.5% of the total number of shares of common stock outstanding on December 31 st of the preceding calendar year, (2) 600,000 shares of common stock or (3) such lesser number of shares of common stock as determined by the Company’s board of directors. As of December 31, 2015, the Company had 378,503 shares reserved for future issuance. The Company issued 599,879 shares during the year ended December 31, 2015. 2011 Inducement Award Plan In September 2011, the Company adopted its 2011 Inducement Award Plan (the “2011 Plan”). The 2011 Plan provides for awarding options, stock appreciation rights, restricted stock grants, restricted stock units and other awards to new employees of the Company and its affiliates, including as a result of future business acquisitions. All options under this plan will be designated as non-statutory stock options. The number of shares initially reserved for issuance under the 2011 Plan was 750,000 shares. The exercise price of awards shall be not less than 100% of the fair market value of the Company’s common stock on the date of grant. Each stock appreciation right grant will be denominated in shares of common stock equivalents. Options and stock appreciation rights have a maximum term of ten years measured from the date of grant, subject to earlier termination following the individual’s cessation of service with the Company. In 2015, an additional 100,000 shares were authorized for issuance by the Company’s board of directors. As of December 31, 2015, stock options to purchase a total of 396,147 shares of common stock were outstanding under the 2011 Plan and 381,558 shares were reserved for future issuance. Determining Fair Value The Company estimated the fair value of certain stock-based awards using a Black-Scholes-Merton valuation model with the following assumptions: Years ended December 31, Stock options 2015 2014 2013 Weighted-average expected term (years) 5.33 5.36 6.49 Weighted-average volatility 60% 62% 74% Risk-free interest rate 1.37% - 1.85% 1.62% – 2.00% 1.08% – 1.86% Expected dividends — % — % — % Stock appreciation units Weighted-average expected term (years) 3.54 2.34 1.90 Weighted-average volatility 62% 56% 58% Risk-free interest rate 0.25% - 1.57% 0.13% – 1.07% 0.10% – 0.63% Expected dividends — % — % — % ESPP Weighted-average expected term (years) 0.69 0.65 0.73 Weighted-average volatility 58% 54% 48% Risk-free interest rate 0.03% - 0.14% 0.05% – 0.13% 0.09% – 0.16% Expected dividends — % — % — % Expected term. The expected term for stock options was estimated using the Company’s historical exercise behavior and expected future exercise behavior. Vested stock appreciation units first became exercisable upon the expiration of the lock-up period associated with the initial public offering. Therefore, the Company estimated the term of the award based on an average of the weighted-average exercise period and the remaining contractual term. The expected term for the ESPP represents the period of time from the beginning of the offering period to the purchase date. Volatility. Due to the limited history of the trading of the Company’s common stock since the initial public offering in February 2011, the expected volatility used by the Company is based on a combination of its own volatility and the volatility of similar entities. In evaluating similarity, factors such as industry, stage of life cycle, size, and financial leverage are taken into consideration. The term over which volatility was measured was commensurate with the expected term. Risk-free interest rate . The risk-free rate that the Company uses in the Black-Scholes-Merton option valuation model is based on U.S. Treasury zero-coupon issues with remaining terms similar to the expected term on the options. Expected dividends. The Company has never declared or paid any cash dividends and does not plan to pay cash dividends in the foreseeable future, and, therefore, used an expected dividend yield of zero in the valuation model. Stock-Based Compensation Expense The following table summarizes the stock-based compensation expense recognized for the years ended December 31, 2015, 2014 and 2013. Unamortized stock-based compensation costs capitalized as part of inventory were immaterial in each of the periods presented (in thousands): Years ended December 31, 2015 2014 2013 Cost of goods sold $ $ $ Research and development Sales and marketing General and administrative $ $ $ 2014 Stock Option and Stock Appreciation Rights Repricing Offer On December 18, 2014, the Company completed an offer to certain of its current employees (or engaged as a consultant to the Company) to receive the opportunity to reduce the exercise price of certain outstanding eligible options or eligible stock appreciation rights to the closing trading price of the Company’s common stock on December 18, 2014, in exchange for such holders’ agreement to accept a new vesting schedule (the “Repricing Offer”). The eligible stock options and stock appreciation rights covered an aggregate of 2,373,692 shares of the Company’s common stock. On December 18, 2014 , options to purchase 1,948,631 shares of the Company’s common stock and stock appreciation rights to purchase 87,354 shares of the Company’s common stock were repriced in the Repricing Offer. The repriced eligible options and eligible stock appreciation rights had a grant date compensation cost, net of forecasted forfeitures, of approximately $2.6 million, which included incremental compensation cost of approximately $0.9 million . The new exercise price per share for each repriced eligible option or eligible stock appreciation right is $3.50 . Each of the repriced eligible options or eligible stock appreciation rights is subject to a new vesting schedule as follows: 50% of the shares subject to such repriced eligible option or eligible stock appreciation right shall vest and become exercisable on January 1, 2016 , and the remaining 50% shall vest and become exercisable in 12 equal monthly installments on each monthly anniversary thereafter, in each case subject to continued service with the Company on each applicable vesting date; provided, however, that alternative vesting applies to certain eligible options or eligible stock appreciation rights if the expiration date of such eligible options or eligible stock appreciation rights is after January 30, 2016, but on or before January 1, 2017 , then 50% of the shares subject to the repriced awards will vest and become exercisable on January 1, 2016 and the remaining shares will be subject to ratable monthly vesting over the remaining term ending 60 days prior to the expiration date of the repriced awards; if the expiration date of such eligible options or eligible stock appreciation rights is prior to January 30, 2016, then 100% of the shares subject to the repriced awards will vest and become exercisable on the 60 th day prior to the expiration date. Stock Option and Restricted Stock Unit Activity The following table summarizes the Company’s stock option and restricted stock unit, or RSU, activity during the year ended December 31, 2015: Stock Options Restricted Stock Units Weighted Weighted Shares Average Average Available Number of Exercise Number of Grant Date for Grant Shares Price Units Fair Value Balance at December 31, 2014 $ $ Authorized for issuance — $ — — $ — Granted $ $ Exercised/Converted — $ $ Cancelled/Forfeited $ $ Balance at December 31, 2015 $ $ The following table summarizes information about stock options outstanding as of December 31, 2015: Options Outstanding Weighted Weighted Average Average Remaining Aggregate Number of Exercise Contractual Intrinsic Value Shares Price Term (Years) (in Thousands) Vested and expected to vest $ $ Exercisable $ $ The fair value of options vested during the years ended December 31, 2015, 2014 and 2013 was $1.3 million, $1.2 million and $1.1 million, respectively. The intrinsic value of options vested and expected to vest and exercisable as of December 31, 2015 is calculated based on the difference between the exercise price and the fair value of the Company’s common stock as of December 31, 2015. The intrinsic value of options exercised during the years ended December 31, 2015, 2014 and 2013, was $1.6 million, $0.4 million and $0.7 million, respectively. The weighted-average fair value of options granted was $3.87 , $1.89 and $4.65 per share for the years ended December 31, 2015, 2014 and 2013, respectively. At December 31, 2015, there was $7.1 million of unrecognized stock-based compensation expense for stock options, net of estimated forfeitures, which will be recognized over the remaining weighted-average period of 2.0 years. Included in the outstanding stock options at December 31, 2015 are 1.1 million shares of market-based stock options granted to key employees. These options will vest if the average closing price of the Company’s common stock over a period of 20 consecutive trading days is equal to or greater than $15.00 per share and the recipients remain in continuous service with the Company through such period, or fully accelerate and vest in December 2019 . The Company estimated the fair value of its market-based option grants as $4.72 for 2015, $1.65 for 2014 and $4.11 - $5.97 for 2013 using a Monte Carlo simulation model with the assumptions discussed above. The Company recorded approximately $0.9 million of compensation expense for these options in 2015 . The following table summarizes information about RSUs outstanding as of December 31, 2015: Restricted Stock Units Outstanding Weighted Average Weighted Remaining Aggregate Number of Average Contractual Intrinsic Value Shares Exercise Price Term (Years) (in Thousands) Vested and expected to vest $ — $ The fair value of RSUs vested during the years ended December 31, 2015, 2014 and 2013 was $3.3 million , $3.4 million and $2.1 million, respectively. The intrinsic value of RSUs vested and expected to vest as of December 31, 2015 is calculated based on the fair value of the Company’s common stock as of December 31, 2015. The intrinsic value of RSUs converted during the years ended December 31, 2015, 2014 and 2013, was $4.3 million , $1.8 million and $2.9 million, respectively. The weighted-average fair value of RSUs granted was $7.46 , $4.54 and $6.96 per share for the years ended December 31, 2015, 2014 and 2013, respectively. At December 31, 2015, the Company had $7.1 million of unrecognized stock-based compensation expense for RSUs, net of estimated forfeitures, which will be recognized over the remaining weighted-average period of 2.4 years. The majority of the Company’s RSUs that were converted during the years ended December 31, 2015, 2014 and 2013 were net share settled. Upon each settlement date, RSUs were withheld to cover the required withholding tax and the remaining amounts were delivered to the recipient as shares of the Company’s common stock. In 2015, 2014 and 2013, the Company withheld 95,227 , 108,623 and 68,390 shares, respectively, which represented the employees’ minimum statutory obligation for income and other employment taxes and remitted cash of $0.7 million, $0.4 million and $0.6 million, respectively, to the appropriate tax authorities. Stock Appreciation Unit Activity The following table summarizes the Company’s stock appreciation unit activity during the year ended December 31, 2015: Weighted- Stock Average Appreciation Exercise Units Price Stock appreciation units outstanding as of December 31, 2014 $ Stock appreciation units exercised $ Stock appreciation units cancelled $ Stock appreciation units outstanding as of December 31, 2015 $ The fair value of stock appreciation units vested in 2015 and 2014 was immaterial. The fair value of stock appreciation units vested in 2013 was $0.1 million. The intrinsic value of stock appreciation units is calculated based on the difference between the exercise price and the fair value of the Company’s common stock as of December 31, 2015. Cash paid for stock appreciation units exercised was $0.1 million in 2015, immaterial in 2014 and $0.1 million in 2013. As of December 31, 2015 and 2014, the liability for settlement of stock appreciation units was $0.7 million and $0.1 million, respectively, and was included in accrued and other current liabilities on the consolidated balance sheet. Based on the fair value of the stock appreciation units as of December 31, 2015, the Company has $1.7 million of unrecognized stock-based compensation expense for stock appreciation units that will be recognized over the remaining weighted-average period of 3.1 years. Included in the outstanding stock appreciation units at December 31, 2015 were 0.2 million shares of market-based stock appreciation units granted to key employees which were granted during 2013. These market-based units will vest if the average closing price of the Company’s common stock over a period of 20 consecutive trading days is equal to or greater than $15.00 per share and the recipient remains in continuous service with the Company through such period, or will fully accelerate and vest in December 2019. Employee Stock Purchase Plan The Company issued 599,879 shares under the 2010 ESPP during the year ended December 31, 2015. As of December 31, 2015, there was $0.9 million of unrecognized stock-based compensation expense for stock purchase rights that will be recognized over the remaining offering period, through November 2016.

Income taxes

Income taxes	12 Months Ended
	Dec. 31, 2015
Income taxes
Income taxes	15. Income taxes The provision for income taxes is based upon the income (loss) before income taxes as follows (in thousands): Years Ended December 31, 2015 2014 2013 U.S. operations $ $ $ Non-U.S. operations $ $ $ The components of the provision for income taxes consisted of the following (in thousands): Years Ended December 31, 2015 2014 2013 Current Federal $ $ $ State Foreign Deferred Federal — — State — — — Foreign Total provision $ $ $ The provision for income taxes differs from the amount obtained by applying the U.S. federal statutory tax rate as follows (in thousands, except percentages): Years Ended December 31, 2015 2014 2013 Federal statutory rate % % % Tax at federal statutory rate $ $ $ State taxes, net of federal benefit Subpart F income — Nondeductible expenses Stock-based compensation Change in valuation allowance Research and development Foreign rate differences Earn out adjustment not taxable — — Escrow settlement — — Foreign tax credit — Change in prior year deferred balances Acquisition-related costs — — Other Total provision for income taxes from continuing operations $ $ $ Deferred income tax assets and liabilities comprise the following (in thousands): December 31, 2015 2014 Deferred Tax Assets: Net operating loss carryforwards $ $ Federal and state credits Reserves, accruals and other Fixed assets and intangibles Total deferred tax assets Valuation allowance Total deferred tax assets, net of valuation allowance Deferred tax liabilities: Acquired intangibles Net deferred tax assets $ $ Reported as: Current deferred tax assets, included within prepaid expenses and other current assets $ — $ Long term deferred tax assets, included within other long-term assets Current deferred income tax liabilities — Deferred income tax liabilities Net deferred tax assets $ $ The net valuation allowance decreased by $2.3 million in 2015, primarily due to the current year utilization and expiration of U.S. deferred tax assets, and increased by $0.2 million in 2014. The Company did not record a full valuation allowance against its net deferred tax assets in foreign jurisdictions as it believes these deferred tax assets were realizable on a more likely than not basis as of December 31, 2015. Based upon the weight of available evidence, which includes the Company’s historical operating performance and the reported cumulative net losses to date, the Company continues to maintain a full valuation allowance against its net U.S. deferred tax assets with the exception of indefinite deferred tax liabilities. As of December 31, 2015, the Company had federal and state net operating loss, or NOL, carryforwards of $2 07.0 million and $69.2 million, respectively. Federal NOL carryforwards start to expire in 2018 and a portion of the California NOL carryforwards will begin to expire in 2016. There are $2.7 million in NOL carryforwards related to excess tax benefits from stock options which will be credited to additional paid-in capital when realized. At December 31, 2015, the Company also had federal and state research credit carryovers of $6.3 million and $13.1 million, respectively. The federal credits will begin to expire in 2018 and the state credits can be carried forward indefinitely. The Company also had $10.2 million of foreign tax credit carryforwards which will start to expire in 2022 if not utilized. Utilization of NOL carryforwards and carried over tax credits may be subject to substantial annual limitation due to federal and state ownership limitations. The annual limitation may result in the expiration of NOL and tax credit carryforwards before utilization. The deferred tax assets listed above do not include NOL carryforwards that are expected to expire unutilized as a result of existing ownership changes. As of December 31, 2015, the Company’s substantial foreign earnings and profits were included in the U.S. taxable income calculation. The undistributed foreign earnings are immaterial. The Company maintains its position for undistributed foreign earnings to be indefinite, accordingly no tax provision for federal and state income taxes have been provided thereon. Upon distribution of those earnings in the forms of dividends or otherwise, the Company would be subject to U.S. income taxes (subject to adjustment for foreign tax credits). The amount is expected to be immaterial. Effective January 1, 2008, the China Enterprise Income Tax Law, or the EIT law, imposed a single uniform income tax rate of 25% on all China enterprises, including foreign invested enterprises, and eliminates or modifies most of the tax exemptions, reductions and preferential treatment available under the previous tax laws and regulations. As a result, the Company’s China subsidiaries may be subject to the uniform income tax rate of 25% unless they are able to qualify for preferential status. Currently, one of the Company’s China subsidiaries qualified for a preferential 15% tax rate that is available for new and high technology enterprises and has been granted for a 15% tax rate for tax years through 2016 . The Company realized benefits from the reduced tax rate of $0.9 million, $0.5 million and $0.2 million in the years ended December 31, 2015, 2014 and 2013, respectively. At December 31, 2015, the Company’s gross unrecognized tax benefits were approximately $ 20.7 million, of which $0.2 million would impact the effective tax rate if recognized. One or more of these unrecognized tax benefits could be subject to a valuation allowance if and when recognized in a future period, which could impact the timing of any related effective tax rate benefit. The Company does not believe that the amount of unrecognized tax benefits will change significantly in the next twelve months. There were no interest or penalties related to unrecognized tax benefits. The Company’s policy is to classify interest and penalties associated with unrecognized tax benefits as income tax expense. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Balance at December 31, 2012 $ Gross increases for tax positions of prior years Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations Balance at December 31, 2013 Gross increases for tax positions of prior years — Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations Balance at December 31, 2014 Gross increases for tax positions of prior years — Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations — Balance at December 31, 2015 $ The Company’s material tax jurisdictions are the United States federal, California, Japan and China. As a result of NOL carryforwards, substantially all of the Company’s tax years remain open to US federal and state tax examination. All of Japan’s tax years remain open for Japanese tax examination. Tax years for 2010 and forward remain open for Chinese tax examination.

Segment and geographic informat

Segment and geographic information	12 Months Ended
	Dec. 31, 2015
Segment and geographic information
Segment and geographic information	16. Segment and geographic information The Company’s Chief Executive Officer, who is considered to be the chief operating decision maker, manages the Company’s operations as a whole and reviews financial information presented on a consolidated basis for purposes of evaluating financial performance and allocating resources. In 2015, 2014 and 2013, the Company operated in one reportable segment. The Company has aligned its products to High Speed Products and Network Products and Solutions. The following presents revenue by product group (in thousands): Years Ended December 31, 2015 2014 2013 Revenue: High Speed Products $ $ $ Network Products and Solutions Total revenue $ $ $ The following tables set forth the Company’s revenue and asset information by geographic region. Revenue is classified based on the ship to location of the customer. Such classification recognizes that for many customers, including those in North America or in Europe, designated shipping points are often in China or elsewhere in Asia. Long-lived assets in the table below comprise only property, plant and equipment (in thousands): Years Ended December 31, 2015 2014 2013 Revenue: China $ $ $ United States Japan Rest of world Total revenue $ $ $ As of December 31, 2015 2014 Long-lived assets: China $ $ United States Japan Rest of world Total long-lived assets $ $

Selected Quarterly Financial Da

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2015
Selected Quarterly Financial Data
Selected Quarterly Financial Data (unaudited)	17. Selected Quarterly Financial Data (unaudited) The following tables set forth a summary of the Company’s quarterly financial information for each of the four quarters for the years ended December 31, 2015 and 2014: First Second Third Fourth Year ended December 31, 2015 Quarter Quarter Quarter Quarter (In thousands, except per share data) Net revenues $ $ $ $ Gross profit Net income Basic and diluted net income per share $ — $ $ $ Weighted averages shares used to compute basic net income per share Weighted averages shares used to compute diluted net income per share First Second Third Fourth Year ended December 31, 2014 Quarter Quarter Quarter Quarter (In thousands, except per share data) Net revenues $ $ $ $ Gross profit Net (loss) income Basic and diluted net (loss) income per share $ $ $ $ Weighted averages shares used to compute basic net (loss) income per share Weighted averages shares used to compute diluted net (loss) income per share

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2015
Subsequent Event
Subsequent Event	18. Subsequent Event Subsequent event, through the filing of this report, included the following: Repayment of Comerica Credit Facility In January 2016, the Company repaid the outstanding balance under the Comerica credit facility, which was $23.8 million as of December 31, 2015.

Summary of significant accoun27

Summary of significant accounting policies (policies)	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Reclassification	Reclassification Reclassification has been made within other accrued expense amount to separate income and other taxes payable and accrued warranty from other in the prior year (Note 8) in order to conform to the current year’s presentation .
Use of estimates	Use of estimates The preparation of financial statements in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported revenue and expenses during the reporting period. Significant estimates made by management include: the useful lives of property, plant and equipment and intangible assets as well as future cash flows to be generated by those assets; fair values of identifiable assets acquired and liabilities assumed in business combinations; allowances for doubtful accounts; valuation allowances for deferred tax assets; write off of excess and obsolete inventories; the valuation of the penalty payment derivative and the valuations and recognition of stock-based compensation, among others. Actual results could differ from these estimates.
Concentration of credit risk and significant customers	Concentration of credit risk and significant customers Financial instruments that potentially subject the Company to concentrations of credit risk are primarily cash and cash equivalents and trade accounts receivable. The Company’s investment policy requires cash and cash equivalents to be placed with high-credit quality institutions and limits on the amount of credit risk from any one issuer. The Company performs ongoing credit evaluations of its customers’ financial condition whenever deemed necessary and generally does not require collateral. The Company maintains an allowance for doubtful accounts based upon the expected collectability of all accounts receivable, which takes into consideration an analysis of historical bad debts, specific customer creditworthiness and current economic trends. For the year ended December 31, 2015, two customers accounted for 44% and 21% of the Company’s total revenue. For the year ended December 31, 2014, three customers accounted for 38% , 15% and 10% of the Company’s total revenue. For the year ended December 31, 2013, three customers accounted for 27% , 16% and 14% of the Company’s total revenue. No other customers accounted for 10% or more of total revenue in any year presented. As of December 31, 2015, one customer accounted for 59% of the Company’s total accounts receivable and as of December 31, 2014, three customers accounted for 26% , 19% and 10% of the Company’s total accounts receivable. No other customers accounted for 10% or more of total accounts receivable as of December 31, 2015 or 2014.
Restricted cash	Restricted cash As a condition of the notes payable lending arrangements of the Company’s subsidiaries in China and, in 2014, the Company’s bank term loan agreement, the Company is required to keep a compensating balance at the issuing banks. These balances have been excluded from the Company’s cash and cash equivalents balance and are classified as restricted cash and investments in the Company’s consolidated balance sheets. As of December 31, 2015 and 2014, the amount of restricted cash and investments was $ 2.7 million and $21. 3 million , respectively.
Cash, cash equivalents and investments	Cash, cash equivalents and investments Highly liquid investments with a maturity of 90 days or less at the date of purchase are considered cash equivalents, with the exception of money market funds and commercial paper which are classified as short-term investments. The Company regularly reviews its investment portfolio to identify and evaluate investments that have indications of possible impairment. Factors considered in determining whether a loss is other-than-temporary include: the length of time and extent to which the fair market value has been lower than the cost basis, the financial condition and near-term prospects of the investee, credit quality, likelihood of recovery, and the Company’s ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in fair market value. Unrealized gains and losses, net of tax, are included in accumulated other comprehensive (loss) income as a separate component of stockholders’ equity on the consolidated balance sheets. The amortization of premiums and discounts on the investments, and realized gains and losses on available-for-sale securities are included in other income (expense), net in the consolidated statements of operations. The Company uses the specific-identification method to determine cost in calculating realized gains and losses upon sale of its marketable securities. Marketable securities are reported at fair value and are classified as available-for-sale investments in our current assets because they represent investments of cash available for current operations.
Fair Value Measurements	Fair Value Measurements Fair value is defined as the price at which an asset could be exchanged in a current transaction between knowledgeable, willing parties. A liability’s fair value is defined as the amount that would be paid to transfer the liability to a new obligor, not the amount that would be paid to settle the liability with the creditor. Where available, fair value is based on observable market prices or parameters or derived from such prices or parameters. Where observable prices or inputs are not available, valuation models are applied. These valuation techniques involve some level of management estimation and judgment, the degree of which is dependent on the price transparency for the instruments or market and the instruments’ complexity. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative accounting guidance describes a fair value hierarchy based on three levels of inputs that may be used to measure fair value, of which the first two are considered observable and the last is considered unobservable. These levels of inputs are as follows: Level 1—Observable inputs such as unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date. Level 2—Inputs (other than quoted prices included in Level 1) are either directly or indirectly observable for the asset or liability. These include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active. Level 3—Unobservable inputs that reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model. For marketable securities measured at fair value using Level 2 inputs, we review trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical securities is not available, we use market pricing and other observable market inputs for similar securities obtained from various third party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data.
Accounts receivable	Accounts receivable Accounts receivable include trade receivables and notes receivable from customers. The notes are generally due within six months. The Company receives notes receivable in exchange for accounts receivable from certain customers in China that are secured by the customer’s affiliated financial institution. An allowance for doubtful accounts is calculated based on the aging of the Company’s trade receivables, historical experience, and management judgment. The Company writes off trade receivables against the allowance when management determines a balance is uncollectible and is no longer actively pursuing collection of the receivable.
Inventories	Inventories Inventories consist of on-hand raw materials, work-in-progress inventories and finished goods. Raw materials and work-in-progress inventories are stored mainly on the Company’s premises. Finished goods are stored on the Company’s premises as well as on consignment at certain customer sites. Inventories are stated at the lower of standard cost, which approximates actual cost determined on the weighted average basis, or market value. Inventories are recorded using the first-in, first-out method. The Company routinely evaluates quantities and values of inventories in light of current market conditions and market trends, and records a write-down for quantities in excess of demand and product obsolescence. The evaluation may take into consideration historic usage, expected demand, anticipated sales price, new product development schedules, the effect new products might have on the sale of existing products, product obsolescence, customer concentrations, product merchantability and other factors. Market conditions are subject to change and actual consumption of inventory could differ from forecasted demand. The Company also regularly reviews the cost of inventories against their estimated market value and records a lower of cost or market write-down for inventories that have a cost in excess of estimated market value, resulting in a new cost basis for the related inventories which is not reversed.
Business Combinations	Business Combinations We allocate the fair value of purchase consideration to the tangible and intangible assets acquired and liabilities assumed based on their estimated fair values. The excess of the fair value of purchase consideration over the fair values of these identifiable assets and liabilities is recorded as goodwill. When determining the fair values of assets acquired and liabilities assumed, management makes significant estimates and assumptions. Fair value estimates are based on the assumptions management believes a market participant would use in pricing the asset or liability. Critical estimates in valuing certain intangible assets include, but are not limited to, future expected cash flows from customer relationships and acquired patents and developed technology; and discount rates. Management’s estimates of fair value are based upon assumptions believed to be reasonable, but which are inherently uncertain and unpredictable and, as a result, actual results may differ from estimates. Amounts recorded in a business combination may change during the measurement period, which is a period not to exceed one year from the date of acquisition, as additional information about conditions existing at the acquisition date becomes available.
Goodwill	Goodwill Goodwill is reviewed for impairment annually in the fourth fiscal quarter or more frequently if events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable. The Company will assess the qualitative factors to determine whether it is more likely than not that the fair value of its single reporting operating unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment. If the Company determines that it is more likely than not that its fair value is less than its carrying amount, then the two-step goodwill impairment test is performed. The first step, identifying a potential impairment, compares the fair value of the reporting unit with its carrying amount. If the carrying amount exceeds its fair value, the second step would need to be performed; otherwise, no further steps are required. The second step, measuring the impairment loss, compares the implied fair value of the goodwill with the carrying amount of the goodwill. Any excess of the goodwill carrying amount over the implied fair value is recognized as an impairment loss, and the carrying value of goodwill is written down to fair value. The Company did not have any goodwill impairment in 2015. There was no goodwill as of December 31, 2014.
Long-lived assets	Long-lived assets Property, plant and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization is computed using the straight-line method over the following estimated useful lives: Buildings 20 - 30 years Machinery and equipment 2 - 7 years Furniture, fixtures and office equipment 3 - 5 years Software 5 - 7 years Leasehold improvements life of the asset or lease term, if shorter Repairs and maintenance costs are expensed as incurred. Intangible assets acquired in a business combination are recorded at fair value. Identifiable finite-lived intangible assets are amortized over the period of estimated benefit using the straight-line method, reflecting the pattern of economic benefits associated with these assets. The estimated useful lives of the Company’s finite-lived intangible assets generally range from two to seven years. The acquired land use rights in China have an estimated useful life of 45 years. The carrying value of intangible assets and other long-lived assets is reviewed on a regular basis for the existence of facts or circumstances, both internally and externally, that may suggest impairment. Some factors which the Company considers to be triggering events for impairment review include a significant decrease in the market value of an asset, a significant change in the extent or manner in which an asset is used, a significant adverse change in the business climate that could affect the value of an asset, an accumulation of costs for an asset in excess of the amount originally expected, a current period operating loss or cash flow decline combined with a history of operating loss or cash flow uses or a projection that demonstrates continuing losses and a current expectation that, it is more likely than not, a long-lived asset will be disposed of at a loss before the end of its estimated useful life. If one or more of such facts or circumstances exist, the Company will evaluate the carrying value of long-lived assets to determine if impairment exists by comparing it to estimated undiscounted future cash flows over the remaining useful life of the assets. If the carrying value of the assets is greater than the estimated future cash flow, the assets are written down to the estimated fair value. The Company’s cash flow estimates contain management’s best estimates, using appropriate and customary assumptions and projections at the time. Any write-down would be treated as a permanent reduction in the carrying amount of the asset and an operating loss would be recognized. The Company recor ded asset impairment charges of $0.4 million in 2015 related to certain held-for-sale assets property, plant and equipment and $1.1 million in 2014 related to certain leasehold improvements. The Company had no asset impairment charge in 2013.
Revenue recognition	Revenue recognition Revenue is derived from the sale of the Company’s products. The Company recognizes revenue provided that persuasive evidence of an arrangement exists, delivery has occurred, the price is fixed or determinable and collectability is reasonably assured. Contracts and/or customer purchase orders are used to determine the existence of an arrangement. Delivery is considered to have occurred when title and risk of loss have transferred to the customer. The price is equal to the amount invoiced to the customer and is not subject to adjustment and customers do not have the right of return. The Company evaluates the creditworthiness of its customers to determine that appropriate credit limits are established prior to the acceptance of an order. Revenue is recognized when the product is shipped and title has transferred to the buyer. The Company bears all costs and risks of loss or damage to the goods up to that point. On most orders, the Company’s shipment terms provide that title passes to the buyer upon shipment by the Company. Other shipment terms may provide that title passes to the buyer upon delivery of the goods to the buyer. Revenue related to the sale of consignment inventory at customer vendor managed locations is not recognized until the product is pulled from inventory stock by customers. Shipping and handling costs are included in the cost of goods sold. The Company presents revenue net of sales taxes and any similar assessments.
Product warranties	Product warranties The Company generally provides warranties to cover defects in workmanship, materials and manufacturing for a period of one to three years to meet the stated functionality as agreed to in each sales arrangement. Products are tested against specified functionality requirements prior to delivery, but the Company nevertheless from time to time experiences claims under its warranty guarantees. The Company accrues for estimated warranty costs under those guarantees based upon historical experience, and for specific items, at the time their existence is known and the amounts are determinable.
Research and development	Research and development Research and development expense consists of personnel costs, including stock-based compensation expense, for the Company’s research and development personnel and product development costs, including engineering services, development software and hardware tools, depreciation of capital equipment and facility costs. Research and development costs are expensed as incurred.
Advertising costs	Advertising costs Advertising costs are expensed as incurred and, to date, have not been significant.
Stock-based compensation	Stock-based compensation The Company grants stock-based awards to employees, consultants and directors. The stock-based awards, including stock options, restricted stock units, employee stock purchase rights, stock appreciation units and market-based awards, are accounted for at estimated fair values. The Company generally determines the fair value of stock options and stock appreciation rights utilizing the Black-Scholes-Merton option-pricing model, or a lattice-binomial option-pricing model for stock-based awards with a market condition. The fair value of employee options is measured on the date of grant and then recognized over the period during which an employee is required to provide services in exchange for the award, known as the requisite service period (usually the vesting period) on a straight-line basis. The Company records expense and an equal adjustment to the liability for stock appreciation units equal to the fair value of the vested portion of the awards as of each period end. Each reporting period thereafter, compensation expense will be recorded based on the remaining service period and the then fair value of the award until vesting of the award is completed. After vesting is completed, the Company will continue to re-measure the fair value of the liability each reporting period until the award is exercised or expires, with changes in the fair value of the liability recorded in the consolidated statements of operations. Restricted stock units are valued at the closing sales price as quoted on the New York Stock Exchange on the date of grant, and are converted into shares of common stock upon vesting on a one-for-one basis. Vesting of restricted stock units is subject to the employee’s continuing service to the Company. The compensation expense related to the restricted stock units is determined using the fair value of common stock on the date of grant, and the expense is recognized on a straight-line basis over the vesting period. Employee stock purchase rights are accounted for at fair value, utilizing the Black-Scholes-Merton option-pricing model. The expense for each purchase period is recognized on a straight-line basis over the requisite service period, from the beginning of the offering period through the respective purchase date. Stock-based compensation expense for modified stock-based awards are recognized using the pool approach, under which the remaining compensation cost from the original awards plus the incremental costs, if any, of the related modified awards is recognized in its entirety over the remaining portion of the requisition service period of the corresponding modified awards. Stock-based compensation expense recognized at fair value includes the impact of estimated forfeitures. The Company estimates future forfeitures at the date of grant and revises the estimates, if necessary, in subsequent periods if actual forfeitures differ from those estimates.
Income taxes	Income taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the carrying amounts of existing assets and liabilities in the financial statements and their respective tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities from a change in tax rates is recognized in the consolidated statement of operations in the period that includes the enactment date. The Company operates in various tax jurisdictions and is subject to audit by various tax authorities. In preparing the Company’s consolidated financial statements, the Company is required to estimate its taxes in each of the jurisdictions in which it operates. The Company estimates actual current tax exposure as well as assesses temporary differences resulting from different treatment of items, such as accruals and allowances not currently deductible for tax purposes. These differences result in deferred tax assets which represent future tax benefits to be received when certain expenses previously recognized in the financial statements become deductible expenses under applicable income tax laws, or loss credit carryforwards are utilized. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of a deferred tax asset will be realized. 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. A valuation allowance is recorded for loss carryforwards and other deferred tax assets where it is more likely than not that such deferred tax assets will not be realized. In November 2015, the Financial Accounting Standards Board (“FASB”) issued ASU 2015-17, Income Taxes (Topic 740): Balance Sheet Classification of Deferred Taxes (“ASU 2015-17”). ASU 2015-17 eliminates the current requirement for organizations to present deferred tax liabilities and assets as current and noncurrent in a classified balance sheet. Instead, organizations will be required to classify all deferred tax assets and liabilities as noncurrent. ASU 2015-17 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2016, with early adoption permitted. The Company early adopted this standard, on a prospective basis, for its financial statements as of and for the year ended December 31, 2015. The Company’s adoption of this standard reduced its prepaid and other current assets and its accrued and other current liabilities while increased its other long-term assets and long term deferred tax liabilities by the corresponding amounts on its consolidated balance sheet as of December 31, 2015.
Foreign currency	Foreign currency Generally the functional currency of the Company’s international subsidiaries is the local currency. The Company translates the financial statements of these subsidiaries to U.S. dollars using month-end rates of exchange for assets and liabilities, and average rates of exchange for revenue, costs, and expenses. Translation gains and losses are recorded in accumulated other comprehensive (loss) income as a component of stockholders’ equity. Net gains resulting from foreign exchange transactions were $3.4 million, $ 3.1 million, and $0. 9 million for the years ended December 31, 2015, 2014, and 2013, respectively. These gains and losses were recorded as other income, net in the Company’s consolidated statements of operations.
Net income (loss) per share	Net income (loss) per share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share is calculated by dividing net income (loss) by the weighted average number of common shares and potential dilutive common share equivalents outstanding during the period if the effect is dilutive.
Recent accounting pronouncements	Recent accounting pronouncements In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) (“ASU 2016-02”). ASU 2016-02 introduces a lessee model that requires recognition of assets and liabilities arising from qualified leases on the consolidated balance sheets and consolidated statements of operations and to disclose qualitative and quantitative information about lease transactions. This guidance is effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities (“ASU 2016-01”). ASU 2016-01 revises an entity’s accounting related to (1) the classification and measurement of investments in equity securities and (2) the presentation of certain fair value changes for financial liabilities measured at fair value. It also amends certain disclosure requirements associated with the fair value of financial instruments. ASU 2016-01 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2017, with early adoption permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory (“ASU 2015-11”). ASU 2015-11 requires entities to measure most inventory “at the lower of cost and net realizable value” but does not apply to inventories that are measured by using either the last-in, first-out method or the retail inventory method. For the Company, this ASU is effective for annual and interim periods beginning after December 15, 2016. Early adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In May 2014, the FASB issued ASU N o. 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”). The standard provides companies with a single model for use in accounting for revenue arising from contracts with customers and supersedes current revenue recognition guidance, including industry-specific revenue guidance. The core principle of the model is to recognize revenue when control of the goods or services transfers to the customer, as opposed to recognizing revenue when the risks and rewards transfer to the customer under the existing revenue guidance. ASU 2014-09 is effective for annual and interim reporting periods beginning after December 15, 2016. Early adoption is not permitted. In August 2015, the FASB issued an accounting standard update for a one-year deferral of the effective date of ASU 2014-09 to annual and interim periods beginning after December 15, 2017 and permits entities to early adopt the standard of ASU 2014-09 for annual and interim reporting periods beginning after December 15, 2016. Companies are permitted to either apply the requirements retrospectively to all prior periods presented, or apply the requirements in the year of adoption, through a cumulative adjustment. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements.

Summary of significant accoun28

Summary of significant accounting policies (Tables)	12 Months Ended
	Dec. 31, 2015
Summary of significant accounting policies
Estimated Useful Lives of Property, Plant and Equipment	Property, plant and equipment are stated at cost, net of accumulated depreciation and amortization. Depreciation and amortization is computed using the straight-line method over the following estimated useful lives: Buildings 20 - 30 years Machinery and equipment 2 - 7 years Furniture, fixtures and office equipment 3 - 5 years Software 5 - 7 years Leasehold improvements life of the asset or lease term, if shorter

Cash, cash equivalents and sh29

Cash, cash equivalents and short-term investments and restricted cash and investments (Tables)	12 Months Ended
	Dec. 31, 2015
Restricted Cash and Investment
Summary of Cash, Cash Equivalents and Short-Term investments and Restricted Cash and Investments	The following table summarizes the Company’s cash, cash equivalents, short-term investments, and restricted cash and investments at December 31, 2015 and 2014 (in thousands): December 31, December 31, 2015 2014 Cash and cash equivalents: Cash $ $ Cash equivalents — Cash and cash equivalents $ $ Short-term investments $ $ — Restricted cash and investments: Restricted cash and investments, current $ $ Restricted cash and investments, non-current — Total restricted cash and investments $ $
Summary of Unrealized Gains and Losses Related to Cash Equivalents and Investments in Marketable Securities	The following table summarizes the Company’s unrealized gains and losses related to the cash equivalents, short-term investments and restricted investments in marketable securities designated as available-for-sale (in thousands): As of December 31, 2015 As of December 31, 2014 Gross Gross Gross Gross Amortized Unrealized Unrealized Fair Amortized Unrealized Unrealized Fair Cost Gains Losses Value Cost Gains Losses Value Marketable securities: Money market accounts $ $ — $ — $ $ — $ — $ — $ — Money market funds — — — — Corporate bonds — — Government-sponsored enterprise obligations — — — — — Commercial paper — — — — — — U.S. government securities — — — — — Sovereign government bonds — Variable rate demand notes — — — — — — Total $ $ — $ $ $ $ $ — $ Reported as: Cash equivalents $ $ — $ — $ $ — $ — $ — $ — Short-term investments — — — — — Restricted cash and investments, non-current — — — — — Total $ $ — $ $ $ $ $ — $
Maturities of Marketable Securities	As of December 31, 2015 and 2014, maturities of marketable securities were as follows (in thousands): December 31, December 31, 2015 2014 Less than 1 year $ $ Due in 1 to 2 years — Due after 5 years — Total $ $

Fair value measurements (Tables

Fair value measurements (Tables)	12 Months Ended
	Dec. 31, 2015
Fair value measurements
Fair Value of Financial Assets	The following table presents the Company’s assets that are measured at fair value on a recurring basis (in thousands): As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Cash equivalents, short-term investments and restricted investments: Money market funds $ $ — $ — $ $ $ — $ — $ Money market accounts — — — — — — Corporate bonds — — — — Government-sponsored enterprise obligations — — — — — — Commercial papers — — — — — — U.S. government securities — — — — — — Sovereign government bonds — — — — — — Variable rate demand notes — — — — — — Total $ $ $ — $ $ $ $ — $ Mutual funds held in Rabbi Trust, recorded in other long-term assets $ $ — $ — $ $ $ — $ — $
Fair Value of Financial Liabilities	The following table presents the Company’s liabilities that are measured at fair value on a recurring basis (in thousands): As of December 31, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Penalty payment derivative (Note 12) $ — $ — $ $ $ — $ — $ $

Net income (loss) per Share (Ta

Net income (loss) per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Net income (loss) per share
Computation of Basic and Diluted Net Income (Loss) per Share	The following table sets forth the computation of the basic and diluted net income (loss) per share attributable to NeoPhotonics Corporation common stockholders for the periods indicated (in thousands, except per share amounts): Years Ended December 31, 2015 2014 2013 Numerator: Net income (loss) $ $ $ Denominator: Weighted average shares used to compute per share amount: Basic Dilutive effect of equity awards — — Diluted Basic net income (loss) per share $ $ $ Diluted net income (loss) per share $ $ $
Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss per Share Attributable to Common Stockholders	The Company has excluded the impact of the following outstanding employee stock options, restricted stock units, common stock warrants and shares expected to be issued under its employee stock purchase plan from the computation of diluted net income (loss) per share, as their effect would have been antidilutive (in thousands): December 31, 2015 2014 2013 Employee stock options Restricted stock units Employee stock purchase plan Common stock warrants — —

Business combinations (Tables)

Business combinations (Tables)	12 Months Ended
	Dec. 31, 2015
Tunable Laser Product Lines From EMCORE Corporation [Member]
Summary of Purchase Accounting and Tangible and Intangible Assets Acquired and Liabilities Assumed	The following table summarizes the allocation of the assets acquired and liabilities assumed as of the acquisition date and subsequent adjustments (in thousands): Total purchase consideration: Cash paid $ Notes payable Total $ Fair value of assets acquired: Accounts receivable $ Inventories Prepaid expenses and other current assets Property, plant and equipment Intangible assets acquired: Developed technology Customer relationships Total $ Less: fair value of liabilities assumed: Accounts payable $ Accrued liabilities Total $ Goodwill $
Schedule Of Finite Lived Intangible Assets Table [Text Block]	The following table presents details of the purchase price allocated to the acquired intangible assets at the acquisition date: Useful Purchased Life intangible assets (In years) (In thousands) Developed technology 7 $ Customer relationships 2 Total purchased intangible assets $
Pro forma Information for Business Acquisition	The unaudited pro forma results do not assume any operating efficiencies as a result of the consolidation of operations (in thousands, except per share data): Year ended December 31, 2015 2014 Revenue $ $ Net income (loss) $ $ Basic net income (loss) per share $ $ Diluted net income (loss) per share $ $
NeoPhotonics Semiconductor [Member]
Summary of Purchase Accounting and Tangible and Intangible Assets Acquired and Liabilities Assumed	The following table summarizes the acquisition accounting and the tangible and intangible assets acquired as of the date of acquisition and subsequent adjustments (in thousands): Total purchase consideration: Cash paid $ Notes payable $ Liabilities assumed: Pension and retirement obligations $ Other compensation-related liabilities Other current liabilities $ Fair value of assets acquired: Inventory $ Other current assets Land, property, plant and equipment Intangible assets acquired: Developed technology Customer relationships $
Pro forma Information for Business Acquisition	The following unaudited pro forma results for the years ended December 31, 2015, 2014 and 2013 do not assume any operating efficiencies as a result of the consolidation of operations (in thousands, except per share data): 2015 2014 2013 Revenue $ $ $ Net income (loss) $ $ ) $ ) Basic net income (loss) per share $ $ ) $ ) Diluted net income (loss) per share $ $ ) $ )

Purchased intangible assets (Ta

Purchased intangible assets (Tables)	12 Months Ended
	Dec. 31, 2015
Purchased intangible assets
Purchased Intangible Assets	Purchased intangible assets consist of the following (in thousands): December 31, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Assets Amortization Assets Assets Amortization Assets Technology and patents $ $ $ $ $ $ Customer relationships Leasehold interest Supplier relationships and other — — — — $ $ $ $ $ $
Amortization Expense of Purchased Intangible Assets	The following table presents details of the amortization expense of the Company’s purchased intangible assets as reported in the consolidated statements of operations (in thousands): Years ended December 31, 2015 2014 2013 Cost of goods sold $ $ $ Operating expenses Total $ $ $
Estimated Future Amortization Expense of Purchased Intangible Assets	The estimated future amortization expense of purchased intangible assets as of December 31, 2015, is as follows (in thousands): 2016 $ 2017 2018 2019 2020 Thereafter $

Balance sheet components (Table

Balance sheet components (Tables)	12 Months Ended
	Dec. 31, 2015
Balance Sheet Components [Abstract]
Restricted cash and investments	Restricted cash and investments were as follows (See Note 10) (in thousands): December 31, 2015 2014 Restricted in connection with notes payable $ $ Restricted in connection with Comerica Bank term loan — Total restricted cash and investments $ $ Reported as: Restricted cash and investments $ $ Restricted cash and investments, non-current — Total restricted cash and investments $ $
Accounts Receivable, Net	Accounts receivable, net were as follows (in thousands): December 31, 2015 2014 Accounts receivable $ $ Trade notes receivable Allowance for doubtful accounts $ $
Summary of Movement in Allowance for Doubtful Accounts	The table below summarizes the movement in the Company’s allowance for doubtful accounts (in thousands): Balance at December 31, 2012 $ Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2013 Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2014 Provision for bad debt Write-offs, net of recoveries Balance at December 31, 2015 $
Inventories, net	Inventories were as follows (in thousands): December 31, 2015 2014 Raw materials $ $ Work in process Finished goods $ $
Property, Plant and Equipment, Net	Property, plant and equipment, net were as follows (in thousands): December 31, 2015 2014 Land $ $ Buildings Machinery and equipment Furniture, fixtures, software and office equipment Leasehold improvements Less: Accumulated depreciation $ $
Accrued Expenses and Other Current Liabilities	Accrued and other current liabilities were as follows (in thousands): December 31, 2015 2014 Employee-related $ $ Income and other taxes payable Accrued warranty Penalty payment derivative Deferred income tax liabilities — Other accrued expenses $ $
Summary of Movement in Warranty Accrual	The table below summarizes the movement in the warranty accrual, which is included in accrued and other current liabilities (in thousands): Years ended December 31, 2015 2014 2013 Beginning balance $ $ $ Warranty accruals Assumed warranty from acquisitions — — Settlements Ending balance $ $ $
Other Noncurrent Liabilities	Other noncurrent liabilities were as follows (in thousands): December 31, 2015 2014 Pension and other employee-related $ $ Other $ $

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2015
Restructuring
Restructuring and Related Costs	The following table summarizes the activit ies associated with the restructuring plans during the years ended December 31, 2015, 2014 and 2013 (in thousands): Workforce Contract Reduction Facilities Termination Total Restructuring obligations, December 31, 2012 $ — $ — $ — $ — Restructuring costs incurred Cash payments Non-cash settlements and other — — Restructuring obligations, December 31, 2013 — Restructuring costs incurred — — Cash payments Restructuring obligations, December 31, 2014 — Restructuring costs incurred — — Cash payments — Restructuring obligations, December 31, 2015 $ — $ — $ — $ —

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt
Components of Debt, Obligations, Weighted Average Interest Rate and Additional Fair Value Information Relating to Outstanding Debt Instruments	The table below summarizes the carrying amount and weighted average interest rate of the Company’s notes payable and long-term debt (in thousands, except percentages): December 31, 2015 December 31, 2014 Weighted Weighted Average Average Carrying Interest Carrying Interest Amount Rate Amount Rate Notes payable $ — $ — Bank borrowings-Comerica Bank % — — Short-term borrowing — — % Total notes payable and short-term borrowing $ $ Long-term debt, current and non-current: Bank borrowings-Comerica Bank $ — — $ % Bank borrowings-Mitsubishi Bank % — — Acquisition-related debt — — % Total long-term debt, current and non-current Unaccreted discount within current portion of long-term debt — Unaccreted discount within long-term debt, net of current portion — Total long-term debt, net of unaccreted discount $ $ Reported as: Current portion of long-term debt $ $ Long-term debt, net of current portion Total long-term debt, net of unaccreted discount $ $
Maturities of Long-term Debt	At December 31, 2015, maturities of long-term debt were as follows (in thousands): 2016 $ 2017 2018 2019 2020 Thereafter $

Pension Plans (Tables)

Pension Plans (Tables)	12 Months Ended
	Dec. 31, 2015
Pension Plans
Funded Status Plans	The funded status of these plans for the years ended December 31, 2015 and 2014 was as follows (in thousands): 2015 2014 RAP RAP DBCPP Change in projected benefit obligation: Projected benefit obligation, beginning of period $ $ $ Service cost — Interest cost Benefits paid — Actuarial (gain)/loss Curtailment/Settlement — Transfer from DBCPP to RAP — Currency translation adjustment Projected benefit obligation, end of period $ $ $ — Change in plan assets: Plan assets at fair value, beginning of period $ — $ — $ Employer contributions — — Benefits paid — — Actual return on plan assets — — — Transfer to DCP — — Currency translation adjustment — — Plan assets at calculated amount, end of period $ — $ — $ — Amounts recognized in consolidated balance sheets: Accrued and other current liabilities $ $ $ — Other noncurrent liabilities $ $ $ — Amount recognized in accumulated other comprehensive loss: Defined benefit pension plans adjustment $ $ $ — Accumulated benefit obligation, end of period $ $ $ —
Periodic Pension Cost	Net periodic pension cost associated with these plans for the years ended December 31, 2015 and 2014 and the period from March 29, 2013 to December 31, 2013 included the following components (in thousands): Year ended December 31, Year ended December 31, Period from March 28, 2013 2015 2014 to December 31, 2013 RAP RAP DBCPP RAP DBCPP Service cost $ — $ $ $ $ Interest cost Expected return on plan assets — — — — Other — — — — Curtailment/settlement (gain) loss — — — Net periodic pension (gain) costs $ $ $ $ $
Estimated Future Benefit Payments Under Plans	Estimated future benefit payments under the RAP are as follows (in thousands): 2016 $ 2017 2018 2019 2020 2021 - 2025 Thereafter $

Commitments and contingencies (

Commitments and contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Future Minimum Commitments Under All Operating Leases	The Company leases various facilities under non-cancelable operating leases. As of December 31, 2015, the future minimum commitments under the Company’s non-cancelable operating leases are as follows (in thousands): Years ending December 31, 2016 $ 2017 2018 2019 2020 Thereafter $

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Stockholders’ Equity
Schedule of Accumulated Other Comprehensive Income, Net of Related Taxes	The following table shows the components of accumulated other comprehensive (loss) income, net of taxes, as of December 31, 2015, 2014 and 2013 (in thousands): 2015 2014 2013 Foreign currency translation adjustments $ $ $ Unrealized gains on available-for-sale securities Defined benefit pension plan adjustment $ $ $

Stock-based compensation (Table

Stock-based compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Stock-based compensation
Estimated Fair Value of Certain Stock-Based Awards Using Black-Scholes-Merton Valuation Model	The Company estimated the fair value of certain stock-based awards using a Black-Scholes-Merton valuation model with the following assumptions: Years ended December 31, Stock options 2015 2014 2013 Weighted-average expected term (years) 5.33 5.36 6.49 Weighted-average volatility 60% 62% 74% Risk-free interest rate 1.37% - 1.85% 1.62% – 2.00% 1.08% – 1.86% Expected dividends — % — % — % Stock appreciation units Weighted-average expected term (years) 3.54 2.34 1.90 Weighted-average volatility 62% 56% 58% Risk-free interest rate 0.25% - 1.57% 0.13% – 1.07% 0.10% – 0.63% Expected dividends — % — % — % ESPP Weighted-average expected term (years) 0.69 0.65 0.73 Weighted-average volatility 58% 54% 48% Risk-free interest rate 0.03% - 0.14% 0.05% – 0.13% 0.09% – 0.16% Expected dividends — % — % — %
Summary of Stock Based Compensation Expense	The following table summarizes the stock-based compensation expense recognized for the years ended December 31, 2015, 2014 and 2013. Unamortized stock-based compensation costs capitalized as part of inventory were immaterial in each of the periods presented (in thousands): Years ended December 31, 2015 2014 2013 Cost of goods sold $ $ $ Research and development Sales and marketing General and administrative $ $ $
Summary of Stock Option and Restricted Stock Unit Activity	The following table summarizes the Company’s stock option and restricted stock unit, or RSU, activity during the year ended December 31, 2015: Stock Options Restricted Stock Units Weighted Weighted Shares Average Average Available Number of Exercise Number of Grant Date for Grant Shares Price Units Fair Value Balance at December 31, 2014 $ $ Authorized for issuance — $ — — $ — Granted $ $ Exercised/Converted — $ $ Cancelled/Forfeited $ $ Balance at December 31, 2015 $ $
Summary of Information about Stock Options Outstanding	The following table summarizes information about stock options outstanding as of December 31, 2015: Options Outstanding Weighted Weighted Average Average Remaining Aggregate Number of Exercise Contractual Intrinsic Value Shares Price Term (Years) (in Thousands) Vested and expected to vest $ $ Exercisable $ $
Summary of Information about Restricted Stock Units Outstanding	The following table summarizes information about RSUs outstanding as of December 31, 2015: Restricted Stock Units Outstanding Weighted Average Weighted Remaining Aggregate Number of Average Contractual Intrinsic Value Shares Exercise Price Term (Years) (in Thousands) Vested and expected to vest $ — $
Summary of Stock Appreciation Unit Activity	The following table summarizes the Company’s stock appreciation unit activity during the year ended December 31, 2015: Weighted- Stock Average Appreciation Exercise Units Price Stock appreciation units outstanding as of December 31, 2014 $ Stock appreciation units exercised $ Stock appreciation units cancelled $ Stock appreciation units outstanding as of December 31, 2015 $

Income taxes (Tables)

Income taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income taxes
Income (Loss) before Income Taxes	The provision for income taxes is based upon the income (loss) before income taxes as follows (in thousands): Years Ended December 31, 2015 2014 2013 U.S. operations $ $ $ Non-U.S. operations $ $ $
Components of Provision for Income Taxes	The components of the provision for income taxes consisted of the following (in thousands): Years Ended December 31, 2015 2014 2013 Current Federal $ $ $ State Foreign Deferred Federal — — State — — — Foreign Total provision $ $ $
Difference in Provision for Income Taxes from Amount Obtained by Applying U.S. Federal Statutory Rate	The provision for income taxes differs from the amount obtained by applying the U.S. federal statutory tax rate as follows (in thousands, except percentages): Years Ended December 31, 2015 2014 2013 Federal statutory rate % % % Tax at federal statutory rate $ $ $ State taxes, net of federal benefit Subpart F income — Nondeductible expenses Stock-based compensation Change in valuation allowance Research and development Foreign rate differences Earn out adjustment not taxable — — Escrow settlement — — Foreign tax credit — Change in prior year deferred balances Acquisition-related costs — — Other Total provision for income taxes from continuing operations $ $ $
Components of Deferred Income Tax Assets and Liabilities	Deferred income tax assets and liabilities comprise the following (in thousands): December 31, 2015 2014 Deferred Tax Assets: Net operating loss carryforwards $ $ Federal and state credits Reserves, accruals and other Fixed assets and intangibles Total deferred tax assets Valuation allowance Total deferred tax assets, net of valuation allowance Deferred tax liabilities: Acquired intangibles Net deferred tax assets $ $ Reported as: Current deferred tax assets, included within prepaid expenses and other current assets $ — $ Long term deferred tax assets, included within other long-term assets Current deferred income tax liabilities — Deferred income tax liabilities Net deferred tax assets $ $
Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Balance at December 31, 2012 $ Gross increases for tax positions of prior years Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations Balance at December 31, 2013 Gross increases for tax positions of prior years — Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations Balance at December 31, 2014 Gross increases for tax positions of prior years — Gross increases for tax positions of current year Reductions resulting from lapse of applicable statute of limitations — Balance at December 31, 2015 $

Segment and geographic inform42

Segment and geographic information (Tables)	12 Months Ended
	Dec. 31, 2015
Segment and geographic information
Revenue and Long-Lived Assets By Geographical Region	The Company has aligned its products to High Speed Products and Network Products and Solutions. The following presents revenue by product group (in thousands): Years Ended December 31, 2015 2014 2013 Revenue: High Speed Products $ $ $ Network Products and Solutions Total revenue $ $ $ The following tables set forth the Company’s revenue and asset information by geographic region. Revenue is classified based on the ship to location of the customer. Such classification recognizes that for many customers, including those in North America or in Europe, designated shipping points are often in China or elsewhere in Asia. Long-lived assets in the table below comprise only property, plant and equipment (in thousands): Years Ended December 31, 2015 2014 2013 Revenue: China $ $ $ United States Japan Rest of world Total revenue $ $ $ As of December 31, 2015 2014 Long-lived assets: China $ $ United States Japan Rest of world Total long-lived assets $ $

Selected Quarterly Financial 43

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Selected Quarterly Financial Data
Summary of Quarterly Financial Information	The following tables set forth a summary of the Company’s quarterly financial information for each of the four quarters for the years ended December 31, 2015 and 2014: First Second Third Fourth Year ended December 31, 2015 Quarter Quarter Quarter Quarter (In thousands, except per share data) Net revenues $ $ $ $ Gross profit Net income Basic and diluted net income per share $ — $ $ $ Weighted averages shares used to compute basic net income per share Weighted averages shares used to compute diluted net income per share First Second Third Fourth Year ended December 31, 2014 Quarter Quarter Quarter Quarter (In thousands, except per share data) Net revenues $ $ $ $ Gross profit Net (loss) income Basic and diluted net (loss) income per share $ $ $ $ Weighted averages shares used to compute basic net (loss) income per share Weighted averages shares used to compute diluted net (loss) income per share

Summary of significant accoun44

Summary of significant accounting policies - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)customer	Dec. 31, 2014USD ($)customer	Dec. 31, 2013USD ($)customer
Summary Of Significant Accounting Policies [Line Items]
Restricted Cash and Investments, Current and Noncurrent	$ 2,660	$ 21,254
Goodwill impairment charges	$ 400	1,100	$ 0
Restricted stock conversion basis	one-for-one
Net gains (losses) resulting from foreign exchange transactions	$ 3,400	$ 3,100	$ 900
Land use rights [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful Life (in years)	45 years
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful Life (in years)	2 years
Product warranty period	1 year
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful Life (in years)	7 years
Product warranty period	3 years
Notes Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Receivable Due Period, general	6 months
Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of customers | customer	2	3	3
Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Number of customers | customer	1	3
Customer Concentration Risk [Member] | Customer One [Member] | Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk	44.00%	38.00%	27.00%
Customer Concentration Risk [Member] | Customer One [Member] | Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk	59.00%	26.00%
Customer Concentration Risk [Member] | Customer Two [Member] | Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk	21.00%	15.00%	16.00%
Customer Concentration Risk [Member] | Customer Two [Member] | Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk		19.00%
Customer Concentration Risk [Member] | Customer Three [Member] | Revenue [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk		10.00%	14.00%
Customer Concentration Risk [Member] | Customer Three [Member] | Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk		10.00%

Summary of significant accoun45

Summary of significant accounting policies - Estimated Useful Lives of Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2015
Minimum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	2 years
Maximum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	20 years
Buildings [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	20 years
Buildings [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	30 years
Machinery and equipment [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	2 years
Machinery and equipment [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	7 years
Furniture, fixtures and office equipment [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	3 years
Furniture, fixtures and office equipment [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	5 years
Software [Member] | Minimum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	5 years
Software [Member] | Maximum [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives (in years)	7 years
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful lives description	life of the asset or lease term, if shorter

Cash, cash equivalents and sh46

Cash, cash equivalents and short-term investments and restricted cash and investments (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash and cash equivalents:
Cash	$ 29,133	$ 43,035
Cash equivalents	46,955
Cash and cash equivalents	76,088	43,035	$ 57,101	$ 36,940
Short-term investments	23,294
Restricted cash and investments:
Restricted cash and investments, current	2,660	5,504
Restricted cash and investments, non-current		15,750
Total restricted cash and investments	$ 2,660	$ 21,254

Summary of Unrealized Gains and

Summary of Unrealized Gains and Losses Related to Cash Equivalents and Investments in Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Available For Sale Securities [Line Items]
Fair Value	$ 70,249	$ 8,297
Gross Unrealized Losses	(29)
Gross Unrealized Gains		6
Amortized Cost	70,278	8,291
Money market accounts [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	46,955
Amortized Cost	46,955
Money market funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	11,318	4,587
Amortized Cost	11,318	4,587
Corporate bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	5,676	2,010
Gross Unrealized Losses	(18)
Gross Unrealized Gains		6
Amortized Cost	5,694	2,004
Government-sponsored enterprise obligations
Schedule Of Available For Sale Securities [Line Items]
Fair Value	3,284
Gross Unrealized Losses	(6)
Amortized Cost	3,290
Commercial papers
Schedule Of Available For Sale Securities [Line Items]
Fair Value	1,398
Amortized Cost	1,398
U.S. government securities
Schedule Of Available For Sale Securities [Line Items]
Fair Value	997
Gross Unrealized Losses	(3)
Amortized Cost	1,000
Sovereign government bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	621
Gross Unrealized Losses	(2)
Amortized Cost	623
Cash equivalents
Schedule Of Available For Sale Securities [Line Items]
Fair Value	46,955
Amortized Cost	46,955
Variable rate demand notes [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	70,249	8,297
Gross Unrealized Losses	(29)
Gross Unrealized Gains		6
Amortized Cost	70,278	8,291
Variable rate demand notes [Member] | Variable rate demand notes [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value		1,700
Amortized Cost		1,700
Short-term investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value	23,294
Gross Unrealized Losses	(29)
Amortized Cost	$ 23,323
Restricted cash and investments, non-current [Member]
Schedule Of Available For Sale Securities [Line Items]
Fair Value		8,297
Gross Unrealized Gains		6
Amortized Cost		$ 8,291

Maturities of Marketable Securi

Maturities of Marketable Securities (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)item	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Fair value measurements
Less than 1 year	$ 66,974	$ 6,597
Due in 1 to 2 years	3,275
Due after 5 years		1,700
Total	70,249	8,297
Impairment losses on its marketable securities	$ 0	$ 0	$ 0
Investments in marketable securities in unrealized loss position in excess of 12 months | item	0

Fair Value Measurements - Measu

Fair Value Measurements - Measurement on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	$ 70,249	$ 8,297
Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	12,315	4,587
Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	57,934	3,710
Money market funds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	11,318	4,587
Money market funds [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	11,318	4,587
Money market accounts [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	46,955
Money market accounts [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	46,955
Corporate bonds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	5,676	2,010
Corporate bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	5,676	2,010
Government-sponsored enterprise obligations
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	3,284
Government-sponsored enterprise obligations | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	3,284
Commercial papers
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	1,398
Commercial papers | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	1,398
U.S. government securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	997
U.S. government securities | Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	997
Sovereign government bonds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	621
Sovereign government bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	621
Variable rate demand notes [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value		1,700
Variable rate demand notes [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value		1,700
Mutual Funds Held in Rabbi Trust [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	435	424
Mutual Funds Held in Rabbi Trust [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	$ 435	$ 424

Fair Value Measurement - Financ

Fair Value Measurement - Financial Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Penalty payment derivative	$ 389	$ 530
Asset impairment charge	368	1,130
Fair Value, Inputs, Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Penalty payment derivative	389	$ 530
Fair Value, Measurements, Recurring [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Benefit due to penalty payment adjustment	100
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Write off of property plant and equipment	200
Write off of assets held for sale	200
Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 3 [Member] | Operating Expenses.
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charge	400
Fair Value, Measurements, Nonrecurring [Member] | Leasehold interest | Fair Value, Inputs, Level 3 [Member] | Operating Expenses.
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Asset impairment charge	$ 1,100

Fair Value Disclosures - Additi

Fair Value Disclosures - Additional information (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Fair value measurements
Transfers between levels of the fair value hierarchy	$ 0	$ 0

Net Income (loss) Per Share - C

Net Income (loss) Per Share - Computation of Basic and Diluted Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator:
Net income (loss)	$ 399	$ 1,378	$ 1,791	$ 100	$ 1,585	$ (1,937)	$ (6,779)	$ (12,588)	$ 3,668	$ (19,719)	$ (34,339)
Denominator:
Basic	40,739	40,367	35,684	32,780	32,640	32,383	31,790	31,610	37,421	32,109	31,000
Dilutive effect of equity awards									1,265
Diluted	42,668	42,217	37,294	33,031	32,710	32,383	31,790	31,610	38,686	32,109	31,000
Basic and diluted net loss per share attributable to NeoPhotonics Corporation common stockholders:
Basic net income (loss) per share									$ 0.10	$ (0.61)	$ (1.11)
Diluted net income (loss) per share									$ 0.09	$ (0.61)	$ (1.11)

Net Income (loss) Per Share - P

Net Income (loss) Per Share - Potentially Dilutive Securities Excluded From Computation of Diluted Net Loss per Share Attributable to Common Stockholders (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	3,448	6,179	5,681
Employee Stock Options.
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	2,176	4,900	4,104
Restricted stock units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	954	656	1,170
Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	318	623	403
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share			4

Business Combinations - Additio

Business Combinations - Additional Information (Details) $ in Thousands, ¥ in Millions	Apr. 16, 2015USD ($)	Jan. 02, 2015USD ($)	Nov. 30, 2015USD ($)	Oct. 31, 2014JPY (¥)	Oct. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Mar. 29, 2013USD ($)
Business Acquisition [Line Items]
Cash consideration paid						$ 422	$ 1,500	$ 13,128
Acquisition-related costs						934	615	5,406
Payment received from escrow account				¥ 111	$ 1,000
Cost Of Goods Sold						240,358	235,059	217,069
Tunable Laser Product Lines From EMCORE Corporation [Member]
Business Acquisition [Line Items]
Total consideration	$ 16,982	$ 17,500
Cash consideration paid	1,500	1,500
Issuance of notes to the seller of acquired business	$ 15,482	$ 16,000
Acquisition-related costs						900
Tunable Laser Product Lines From EMCORE Corporation [Member] | Pro Forma [Member]
Business Acquisition [Line Items]
Acquisition-related costs						300	$ 600
Revenue						$ 55,800
NeoPhotonics Semiconductor [Member]
Business Acquisition [Line Items]
Withheld and placed into escrow									$ 2,000
NeoPhotonics Semiconductor [Member] | Pro Forma [Member]
Business Acquisition [Line Items]
Reduction in Assumed Assets & Liabilities								300
NeoPhotonics Semiconductor [Member] | Pro Forma [Member] | One Time Charges and Amortization of Fair Value Adjustments [Member]
Business Acquisition [Line Items]
Revenue								(1,900)
Cost Of Goods Sold								(1,800)
NeoPhotonics Semiconductor [Member] | Pro Forma [Member] | Change in value of inventory as a result of acquisition accounting [Member]
Business Acquisition [Line Items]
Cost Of Goods Sold								$ (3,200)
EigenLight Corp Member
Business Acquisition [Line Items]
Cash consideration			$ 400

Business Combination - Allocati

Business Combination - Allocation of Assets acquired, liabilites assumed and Purchase price (Details) - USD ($) $ in Thousands	Apr. 16, 2015	Jan. 02, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Total purchase consideration:
Cash paid			$ 422	$ 1,500	$ 13,128
Liabilities assumed:
Goodwill			$ 1,115
Tunable Laser Product Lines From EMCORE Corporation [Member]
Total purchase consideration:
Cash paid	$ 1,500	$ 1,500
Notes payable	15,482	16,000
Total consideration	16,982	17,500
Fair value of assets acquired:
Accounts receivable	9,274
Inventories	1,693
Prepaid expenses and other current assets	670
Property, plant and equipment	6,917
Intangible assets acquired:
Intangible assets acquired		$ 4,800
Fair value of assets acquired	23,354
Liabilities assumed:
Accounts payable	(7,427)
Accrued liabilities	(60)
Fair value of liabilities assumed total	(7,487)
Goodwill	1,115
Tunable Laser Product Lines From EMCORE Corporation [Member] | Developed Technology [Member]
Fair value of assets acquired:
Useful Life (in years)		7 years
Intangible assets acquired:
Intangible assets acquired	4,100	$ 4,100
Tunable Laser Product Lines From EMCORE Corporation [Member] | Customer relationships
Fair value of assets acquired:
Useful Life (in years)		2 years
Intangible assets acquired:
Intangible assets acquired	$ 700	$ 700

Business Combinations - Acquisi

Business Combinations - Acquisition Accounting and Tangible and Intangible Assets Acquired -Liabilities Assumed (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Total purchase consideration:
Cash paid		$ 422	$ 1,500	$ 13,128
Minimum [Member]
Business Acquisition [Line Items]
Property, plant and equipment, useful lives (in years)		2 years
Intangible assets useful life (in years)		2 years
Maximum [Member]
Business Acquisition [Line Items]
Property, plant and equipment, useful lives (in years)		20 years
Intangible assets useful life (in years)		7 years
Developed Technology [Member] | Minimum [Member]
Business Acquisition [Line Items]
Intangible assets useful life (in years)		4 years
Developed Technology [Member] | Maximum [Member]
Business Acquisition [Line Items]
Intangible assets useful life (in years)		5 years
Customer relationships
Business Acquisition [Line Items]
Weighted Average useful life (in years)		6 years
NeoPhotonics Semiconductor [Member]
Business Acquisition [Line Items]
Royalty Rate Percentage		2.00%
Total purchase consideration:
Cash paid	$ 13,128
Notes payable	11,130
Total consideration	24,258
Liabilities assumed:
Pension and retirement obligations	6,471
Other compensation-related liabilities	1,083
Other current liabilities	1,265
Liabilities assumed	8,819
Fair value of assets acquired:
Inventory	13,309
Other current assets	35
Land, property, plant and equipment	14,433
Intangible assets acquired:
Fair value of assets acquired	33,077
NeoPhotonics Semiconductor [Member] | Developed Technology [Member]
Intangible assets acquired:
Intangible assets acquired	2,120
NeoPhotonics Semiconductor [Member] | Customer relationships
Intangible assets acquired:
Intangible assets acquired	$ 3,180

Business Combination - Pro form

Business Combination - Pro forma Information for Business Acquisition (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items]
Revenue	$ 339,439	$ 353,003
Net income (loss)	$ 4,088	$ (23,221)
Basic net income (loss) per share	$ 0.11	$ (0.72)
Diluted net income (loss) per share	$ 0.11	$ (0.72)
NeoPhotonics Semiconductor [Member]
Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items]
Revenue	$ 339,437	$ 306,177	$ 294,933
Net income (loss)	$ 3,931	$ (19,719)	$ (23,340)
Basic net income (loss) per share	$ 0.11	$ (0.61)	$ (0.75)
Diluted net income (loss) per share	$ 0.10	$ (0.61)	$ (0.75)

Purchased intangible assets (De

Purchased intangible assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 53,843	$ 50,996
Accumulated Amortization	(43,991)	(40,733)
Net Assets	9,852	10,263
Technology and patents
Finite Lived Intangible Assets [Line Items]
Gross Assets	37,430	34,023
Accumulated Amortization	(31,061)	(28,402)
Net Assets	6,369	5,621
Customer relationships
Finite Lived Intangible Assets [Line Items]
Gross Assets	15,101	14,725
Accumulated Amortization	(12,623)	(11,176)
Net Assets	2,478	3,549
Leasehold interest
Finite Lived Intangible Assets [Line Items]
Gross Assets	1,312	1,386
Accumulated Amortization	(307)	(293)
Net Assets	$ 1,005	1,093
Supplier relationships and other
Finite Lived Intangible Assets [Line Items]
Gross Assets		862
Accumulated Amortization		$ (862)

Puruchased intangible assets -

Puruchased intangible assets - Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Purchased intangible assets
Cost of goods sold	$ 3,349	$ 2,833	$ 2,543
Operating expenses	1,791	1,502	1,532
Total	$ 5,140	$ 4,335	$ 4,075

Purchased intangible assets - E

Purchased intangible assets - Estimated Future Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Purchased intangible assets
2,016	$ 4,458
2,017	1,323
2,018	1,146
2,019	793
2,020	689
Thereafter	1,443
Net Assets	$ 9,852	$ 10,263

Balance sheet components - Rest

Balance sheet components - Restricted Cash and Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash and investments	$ 2,660	$ 21,254
Restricted cash and investments	2,660	5,504
Restricted cash and investments, non-current		15,750
Notes Payable
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash and investments	$ 2,660	3,754
Comerica Bank Term Loan
Restricted Cash And Cash Equivalents Items [Line Items]
Restricted cash and investments		$ 17,500

Balance sheet components - Acco

Balance sheet components - Accounts Receivable, net (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts receivable, net
Accounts receivable	$ 82,235	$ 69,839
Trade notes receivable	1,769	7,999
Allowance for doubtful accounts	(843)	(241)
Accounts receivable, Net ,Total	$ 83,161	$ 77,597

Balance sheet components - Allo

Balance sheet components - Allowance for Doubtful Accounts (Details) - Allowance for Doubtful Accounts - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation And Qualifying Accounts Disclosure [Line Items]
Beginning Balance	$ (241)	$ (531)	$ (963)
Provision for bad debt	(640)	266	253
Write-offs, net of recoveries	38	24	179
Ending Balance	$ (843)	$ (241)	$ (531)

Balance sheet components - Inve

Balance sheet components - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Inventories
Raw materials	$ 23,793	$ 23,804
Work in process	12,165	13,600
Finished goods	29,644	19,943
Inventories	$ 65,602	$ 57,347

Balance sheet components - Addi

Balance sheet components - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Balance Sheet Components [Abstract]
Finished goods, at vendor managed inventory locations	$ 14.2	$ 6.4

Balance sheet components - Prop

Balance sheet components - Property, Plant and Equipment, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, plant and equipment, net
Land	$ 2,768	$ 2,778
Buildings	21,791	22,338
Machinery and equipment	117,758	105,406
Furniture, fixtures, software and office equipment	9,661	8,730
Leasehold improvements	10,534	8,569
Property, Plant and Equipment, Gross, Total	162,512	147,821
Less: Accumulated depreciation	(99,894)	(90,164)
Property, plant and equipment, net	62,618	57,657
Depreciation expense	17,700	19,100	$ 16,300
Asset impairment charges	$ 368	$ 1,130

Balance sheet components - Accr

Balance sheet components - Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accrued and other current liabilities
Employee-related	$ 17,420	$ 13,635
Income and other taxes payable	3,720	2,071
Accrued warranty	1,175	1,751
Penalty payment derivative	389	530
Deferred income tax liabilities		181
Other accrued expenses	5,246	4,560
Accrued and other current liabilities	$ 27,950	$ 22,728

Balance sheet components- Movem

Balance sheet components- Movement in Warranty Accrual (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Summary of significant accounting policies
Beginning balance	$ 1,751	$ 1,737	$ 1,072
Warranty accruals	79	861	1,514
Assumed warranty from acquisitions			135
Settlements	(655)	(847)	(984)
Ending balance	$ 1,175	$ 1,751	$ 1,737

Balance sheet components - Othe

Balance sheet components - Other Noncurrent Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Other Noncurrent liabilites
Pension and other employee-related	$ 5,036	$ 5,355
Other	2,352	1,871
Other noncurrent liabilities	$ 7,388	$ 7,226

Restructuring - Additional Info

Restructuring - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)facility
Restructuring Cost And Reserve [Line Items]
Restructuring costs incurred	$ 169	$ 1,086	$ 1,474
Number of facilities closed | facility			1
Operating Expenses.
Restructuring Cost And Reserve [Line Items]
Restructuring costs incurred			$ 800
Costs of Goods Sold and Operating Expenses
Restructuring Cost And Reserve [Line Items]
Restructuring costs incurred			$ 1,500

Restructuring - Summary of Rest

Restructuring - Summary of Restructuring Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	$ 154	$ 277
Restructuring costs incurred	169	1,086	$ 1,474
Cash payments	(323)	(1,209)	(1,268)
Non-cash settlements and other			71
Restructuring obligations, ending balance		154	277
Workforce Reduction [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	54
Restructuring costs incurred	169	1,086	699
Cash payments	(223)	(1,032)	(699)
Restructuring obligations, ending balance		54
Facilities [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	100	211
Restructuring costs incurred			318
Cash payments	$ (100)	(111)	(178)
Non-cash settlements and other			71
Restructuring obligations, ending balance		100	211
Contract Termination [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance		66
Restructuring costs incurred			457
Cash payments		$ (66)	(391)
Restructuring obligations, ending balance			$ 66

Debt - Components of Debt, Obli

Debt - Components of Debt, Obligations, Weighted Average Interest Rate (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Notes payable	$ 8,857	$ 12,771
Total notes payable and short-term borrowing	32,657	22,771
Total long-term debt, current and non-current	11,769	23,336
Current portion of long-term debt	760	2,445
Long-term debt, net of current portion	10,759	20,891
Total long-term debt, net of unaccreted discount	11,519	23,336
Bank Borrowings [Member] | Comerica Bank [Member]
Debt Instrument [Line Items]
Short-term borrowing	$ 23,800
Long-term debt, carrying amount		$ 17,500
Short-term Debt Weighted Average Interest Rate	2.99%
Longterm Debt Weighted Average Interest Rate		3.16%
Bank Borrowings [Member] | Mitsubishi Bank [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	$ 11,769
Longterm Debt Weighted Average Interest Rate	1.53%
Short Term Borrowing [Member]
Debt Instrument [Line Items]
Short-term borrowing		$ 10,000
Short-term Debt Weighted Average Interest Rate		3.18%
Long-Term Debt Current [Member]
Debt Instrument [Line Items]
Unaccreted discount within long-term debt, net of current portion	$ (71)
Long-Term Debt Non-Current [Member]
Debt Instrument [Line Items]
Unaccreted discount within long-term debt, net of current portion	$ (179)
NeoPhotonics Semiconductor [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount		$ 5,836
Longterm Debt Weighted Average Interest Rate		1.50%

Debt - Additional Information (

Debt - Additional Information (Details) $ in Thousands, ¥ in Millions

Apr. 16, 2015USD ($)

Feb. 25, 2015JPY (¥)

Feb. 25, 2015USD ($)

Jan. 02, 2015USD ($)

Mar. 29, 2013JPY (¥)

Apr. 30, 2015USD ($)

Feb. 28, 2015JPY (¥)

Feb. 28, 2015USD ($)

Jan. 31, 2015USD ($)

Oct. 31, 2014

Mar. 31, 2013USD ($)

Dec. 31, 2015USD ($)item

Dec. 31, 2014USD ($)

Dec. 31, 2013USD ($)

Dec. 31, 2015CNY (¥)

Dec. 31, 2015JPY (¥)

Dec. 31, 2015USD ($)

Feb. 25, 2015USD ($)

Dec. 31, 2014JPY (¥)

Dec. 31, 2014USD ($)

Debt Instrument [Line Items]

Minimum liquidity ratio

1.5

Repayments Of Notes Payable

$ 25,498

$ 22,090

$ 22,166

China

Debt Instrument [Line Items]

Short-term line of credit facility

$ 8,900

$ 12,800

Bank Borrowings [Member]

Debt Instrument [Line Items]

Compensating Balance, Amount

0

17,500

Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 1,400,000,000

11,800

Comerica [Member] | Bank Borrowings [Member]

Debt Instrument [Line Items]

Short-term line of credit facility

17,500

Libor Plus Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

2.75%

Libor Plus Rate [Member] | Comerica [Member] | Bank Borrowings [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

3.00%

Credit Facility Base Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.75%

Credit Facility Base Rate [Member] | Comerica [Member] | Bank Borrowings [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

2.00%

First Credit Facility Expires June 2016 [Member] | China

Debt Instrument [Line Items]

Percentage of compensating balance requirement for bank acceptance drafts

30.00%

First Short-Term Advance Financing Agreement Expires April 2015 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

$ 5,000

Adjusted LIBOR variable rate term

6 months

Debt Instrument, Basis Spread on Variable Rate

3.30%

First Short-Term Advance Financing Agreement Expires April 2015 [Member] | Libor Plus Rate [Member] | China

Debt Instrument [Line Items]

Obligation bear variable interest

3.71%

Term Loan B [Member] | Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Debt, aggregate principal amount

¥ 1,000,000,000

$ 8,400

Debt, periodic principal payments | ¥

8,333,000

Debt, lump sum payment on the maturity date | ¥

8,373,000

Loan structuring fee including consumption tax

¥ 40,500,000

$ 300

Term Loan B [Member] | Tokyo Interbank Offer Rate [Member] | Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.40%

1.40%

Term Loan A [Member] | Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Due date of the principal

Feb. 23, 2018

Feb. 23, 2018

Debt, aggregate principal amount

¥ 4,200,000

$ 500,000

Term Loan A [Member] | Tokyo Interbank Offer Rate [Member] | Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.40%

1.40%

Senior Secured Revolving Credit Facility Expires November 2016 [Member] | Comerica [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 25,000

30,000

Senior Secured Revolving Credit Facility Expires November 2016 [Member] | Libor Plus Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

2.75%

Senior Secured Revolving Credit Facility Expires November 2016 [Member] | Credit Facility Base Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.75%

Senior Secured Revolving Credit Facility Expires November 2016 [Member] | Federal Funds Effective Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.00%

Senior Secured Revolving Credit Facility Expires November 2016 [Member] | Daily Adjusting LIBOR Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.00%

NeoPhotonics Semiconductor [Member]

Debt Instrument [Line Items]

Notes payable

$ 11,130

NeoPhotonics Semiconductor [Member]

Debt Instrument [Line Items]

Obligation bear interest

1.50%

Tunable Laser Product Lines From EMCORE Corporation [Member]

Debt Instrument [Line Items]

Notes payable

$ 15,482

$ 16,000

Maturity date (in years)

P2Y

Tunable Laser Product Lines From EMCORE Corporation [Member] | First Year [Member]

Debt Instrument [Line Items]

Note payable, interest rate

5.00%

Tunable Laser Product Lines From EMCORE Corporation [Member] | Second Year [Member]

Debt Instrument [Line Items]

Note payable, interest rate

13.00%

Tunable Laser Product Lines From EMCORE Corporation [Member] | Term Loan B [Member] | Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Notes payable

$ 15,500

Notes Payable

Debt Instrument [Line Items]

Compensating Balance, Amount

2,700

3,800

Notes Payable | China

Debt Instrument [Line Items]

Number Of Credit Facilities | item

2

Notes Payable | First Credit Facility Expires June 2016 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 120

18,500

Notes Payable | Second Credit Facility Expires September 2016 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

133

20,500

Notes Payable | NeoPhotonics Semiconductor [Member]

Debt Instrument [Line Items]

Notes payable outstanding

¥ 700,000,000

5,800

Repayments Of Notes Payable

¥ 710,000,000

$ 6,000

Notes Payable | NeoPhotonics Semiconductor [Member] | Notes Payable To be paid in three equal installments [Member]

Debt Instrument [Line Items]

Notes payable | ¥

¥ 1,050,000,000

Bankers Acceptance | First Credit Facility Expires June 2016 [Member] | China

Debt Instrument [Line Items]

Short-term borrowing capacity

¥ 171.4

26,400

Bankers Acceptance | Second Credit Facility Expires September 2016 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 190,000,000

29,300

Percentage of compensating balance requirement for bank acceptance drafts

30.00%

Second Short-Term Advance Financing Agreement | China

Debt Instrument [Line Items]

Short-term line of credit facility

$ 10,000

Due date of the principal

Dec. 31, 2015

Minimum [Member] | Second Short-Term Advance Financing Agreement | China

Debt Instrument [Line Items]

Obligation bear interest

2.33%

2.33%

Maximum [Member] | Second Short-Term Advance Financing Agreement | China

Debt Instrument [Line Items]

Obligation bear interest

4.02%

4.02%

First Credit Facility [Member] | China

Debt Instrument [Line Items]

Credit facility, expiration date

Jun. 30, 2016

Second Credit Facility [Member] | China

Debt Instrument [Line Items]

Credit facility, expiration date

Sep. 30, 2016

Revolving Credit Facility [Member] | Comerica [Member]

Debt Instrument [Line Items]

Short-term line of credit facility

23,800

Line of Credit Facility, Maximum Borrowing Capacity

$ 20,000

Line of Credit Facility, Remaining Borrowing Capacity

$ 30,000

$ 0

Revolving Credit Facility [Member] | Libor Plus Rate [Member] | Comerica [Member]

Debt Instrument [Line Items]

Line of credit facility, interest rate

2.99%

2.99%

2.99%

Debt - Maturities of Long -Term

Debt - Maturities of Long -Term debt (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Maturities Of Long Term Debt [Abstract]
2,016	$ 831
2,017	831
2,018	4,984
2,019	831
2,020	831
Thereafter	3,461
Long Term Debt	$ 11,769	$ 23,336

Pension Plans - Additional Info

Pension Plans - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	May. 31, 2014USD ($)	Mar. 29, 2013item
Defined Benefit Plan Disclosure [Line Items]
Number of Defined Benefit Pension Plans | item					2
Cost of goods sold	$ 240,358	$ 235,059	$ 217,069
Operating Expenses	$ 95,128	90,250	98,846
Reclassification out of Accumulated Other Comprehensive Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Cost of goods sold		200
Operating Expenses		100
DBCPP [Member]
Defined Benefit Plan Disclosure [Line Items]
Plan assets			$ 2,072	$ 2,000
Receivable from LAPIS		$ 300

Pension Plans - Funded Status o

Pension Plans - Funded Status of Plans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014
RAP [Member]
Change in projected benefit obligation:
Projected benefit obligation, beginning of period		$ 5,054	$ 5,446
Service cost	$ 175		39
Interest cost	39	10	29
Benefits paid			(23)
Actuarial (gain)/loss		40	154
Curtailment/Settlement			(408)
Transfer from DBCPP to RAP			490
Currency translation adjustment		(18)	(673)
Projected benefit obligation, end of period	5,446	5,086	5,054
Change in plan assets:
Benefits paid			(23)
Amounts recognized in consolidated balance sheets:
Accrued and other current liabilities		497	123
Other noncurrent liabilities		4,589	4,931
Amount recognized in accumulated other comprehensive loss:
Defined benefit pension plans adjustment		153	113
Accumulated benefit obligation, end of period		$ 5,086	5,054
DBCPP [Member]
Change in projected benefit obligation:
Projected benefit obligation, beginning of period			2,508
Service cost	78		14
Interest cost	18		7
Benefits paid			(76)
Actuarial (gain)/loss			88
Curtailment/Settlement			(2,022)
Transfer from DBCPP to RAP			(569)
Currency translation adjustment			50
Projected benefit obligation, end of period	2,508
Change in plan assets:
Plan assets at fair value, beginning of period			2,072
Employer contributions			15
Benefits paid			(76)
Transfer to DCP			(1,766)
Currency translation adjustment			$ (245)
Plan assets at calculated amount, end of period	$ 2,072

Pension Plans - Periodic Pensio

Pension Plans - Periodic Pension Cost (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Recognized expense		$ 300	$ 300	$ 300
RAP [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 175		39
Interest cost	39	10	29
Curtailment/settlement (gain) loss			(249)
Net periodic pension (gain) costs	214	$ 10	$ (181)
Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate		0.20%	0.20%
DBCPP [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	78		$ 14
Interest cost	18		7
Expected return on plan assets	(30)
Other			1
Curtailment/settlement (gain) loss			133
Net periodic pension (gain) costs	$ 66		$ 155

Pension Plans - Estimated Futur

Pension Plans - Estimated Future Benefit Payments Under Plans (Details) - RAP [Member] $ in Thousands	Dec. 31, 2015USD ($)
Defined Benefit Plan Disclosure [Line Items]
2,016	$ 497
2,017	375
2,018	536
2,019	249
2,020	491
2021 - 2025	1,703
Thereafter	1,235
Total estimated future benefit payments	$ 5,086

Commitments and contingencies -

Commitments and contingencies - Future Minimum Commitments Under All Operating Leases (Details) $ in Thousands	Dec. 31, 2015USD ($)
Leases [Abstract]
2,016	$ 1,225
2,017	1,058
2,018	1,079
2,019	973
2,020	482
Thereafter	578
Operating Leases, Future Minimum Payments Due, Total	$ 5,395

Commitments and Contingencies80

Commitments and Contingencies - Additional Information (Details) € in Millions	May. 21, 2015	Apr. 02, 2015	Mar. 23, 2015EUR (€)	Mar. 23, 2015USD ($)	Sep. 16, 2013USD ($)	May. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Dec. 31, 2010item
Commitments And Contingencies Disclosure [Line Items]
Operating leases, future minimum, sublease receipts							$ 1,400,000
Rent expense							2,200,000	$ 2,200,000	$ 2,200,000
Claims of patent infringement | item										2
Number of law suits | item										4
Number of defendants | item										1
Amount of companies cumulative investment and spending							18,800,000
Penalty amount							$ 1,500,000
Number of days in which penalty needs to be paid							30 days
Cure period							90 days
Amount of contribution							$ 15,400,000
Proceeds from public stock offering, net of offering costs							39,800,000
Operating Leases Rent Expense Net							2,200,000	2,200,000	2,200,000
Penalty payment derivative							389,000	530,000
Securities lock up agreement period	180 days	60 days
Total outstanding purchase obligations							$ 34,800,000
Year of acquisition							Oct. 12, 2011
Fair Value, Inputs, Level 3 [Member]
Commitments And Contingencies Disclosure [Line Items]
Penalty payment derivative							$ 389,000	530,000
Pending Litigation Member
Commitments And Contingencies Disclosure [Line Items]
Partial settlement of claims payment					$ 492,000
Accrual for estimated net litigation expense			€ 1	$ 1,100,000
Private Placement [Member] | Performance Guarantee [Member]
Commitments And Contingencies Disclosure [Line Items]
Other non-current liability							30,000,000
Embedded Derivative Financial Instruments [Member] | Maximum [Member]
Commitments And Contingencies Disclosure [Line Items]
Other non-current liability							5,000,000
Embedded Derivative Financial Instruments [Member] | Private Placement [Member]
Commitments And Contingencies Disclosure [Line Items]
Penalty payment derivative							100,000
Additional paid-in capital							4,900,000
RUSSIAN FEDERATION
Commitments And Contingencies Disclosure [Line Items]
Exit fees							3,500,000
Exit fees for future							$ 2,000,000
Santur Corporation [Member]
Commitments And Contingencies Disclosure [Line Items]
Amount Of Escrow Received						$ 1,900,000
Amount of indemnification claims by the company								3,900,000
Estimated fair value of contingent consideration amount								$ 2,000,000	$ 2,000,000

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Apr. 30, 2015
Class Of Stock [Line Items]
Common Stock Shares Authorized		100,000,000	100,000,000
Common Stock Par Or Stated Value Per Share		$ 0.0025	$ 0.0025
Sale of common stock shares	6,866,689
Sale of common stock upon the exercise of overallotment option	895,655	304,385
Public offering price	$ 7.25
Proceeds From Issuance Of Common Stock		$ 45,648	$ (10)
Underwriting discounts	$ 3,000
Other offering expenses	$ 1,200
Other Comprehensive Income Loss Reclassification Adjustment From AOCI For Sale Of Securities Before Ta		0	0	$ 0
Accumulated deficit subject to restriction		$ 7,900	$ 7,100
Minimum [Member]
Class Of Stock [Line Items]
Accumulated profits		10.00%	10.00%
Employee Stock Options.
Class Of Stock [Line Items]
Common stock		6,926,534
Employee Stock Purchase Plan
Class Of Stock [Line Items]
Common stock		378,503
Private Placement [Member] | Performance Guarantee [Member]
Class Of Stock [Line Items]
Other non-current liability		$ 30,000
Resale Registration Statement [Member]
Class Of Stock [Line Items]
Common Stock Shares Authorized					4,972,905
Common Stock Par Or Stated Value Per Share					$ 0.0025

Stockholders Equity - Accumulat

Stockholders Equity - Accumulated Other Comprehensive Income, Net of Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Stockholders Equity Note [Abstract]
Foreign currency translation adjustment	$ (1,595)	$ 5,391	$ 11,802
Unrealized gains on available-for-sale securities	(29)	6	3
Defined benefit pension plan adjustment	(99)	(71)	(118)
Accumulated other comprehensive (loss) income, net of taxes	$ (1,723)	$ 5,326	$ 11,687

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands	Dec. 18, 2014USD ($)shares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014USD ($)installment$ / sharesshares	Dec. 31, 2013USD ($)$ / sharesshares	Feb. 28, 2011shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		705,051	895,311
Options to purchase shares, outstanding		5,007,797	4,899,713
Authorized for issuance		1,246,325
Expected Time For Repriced Awards			60 days
Remitted cash to appropriate tax authorities | $		$ 727	$ 387	$ 565
Stock Appreciation Units (SARs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options to purchase shares, outstanding		342,316	375,833
Intrinsic value of options exercised | $		$ 100
Performance-based stock appreciation units		1,700,000
Number of days for stock price to be traded above mentioned price		20 days
Minimum closing stock price | $ / shares		$ 15
Employee Stock Options.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost, net of forecasted forfeitures | $		$ 7,100
Fair value of options vested | $		1,300	$ 1,200	1,100
Intrinsic value of options exercised | $		$ 1,600	$ 400	$ 700
Weighted-average fair value of options granted | $ / shares		$ 3.87	$ 1.89	$ 4.65
Remaining weighted-average period		2 years
Stock Option and Restricted Stock Unit Activity [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based stock appreciation units		1,100,000
Number of days for stock price to be traded above mentioned price		20 days
Minimum closing stock price | $ / shares		$ 15
Weighted-average fair value granted | $ / shares		$ 4.72	$ 1.65
Share-based compensation expense | $		$ 900
Stock Option and Restricted Stock Unit Activity [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value granted | $ / shares				4.11
Stock Option and Restricted Stock Unit Activity [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value granted | $ / shares				5.97
Restricted stock units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares outstanding		1,213,686	655,729
Vested (in shares)		557,828
Compensation cost, net of forecasted forfeitures | $		$ 7,100
Remaining weighted-average period		2 years 4 months 24 days
Performance-based stock appreciation units		1,149,334
Weighted-average fair value granted | $ / shares		$ 7.46	$ 4.54	$ 6.96
Stock grants vested value | $		$ 3,300	$ 3,400	$ 2,100
Intrinsic value of units exercised | $		$ 4,300	$ 1,800	$ 2,900
Common stock withheld shares		95,227	108,623	68,390
Remitted cash to appropriate tax authorities | $		$ 700	$ 400	$ 600
Stock Appreciation Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options to purchase shares, outstanding		200,000
Intrinsic value of options exercised | $			100	$ 100
Remaining weighted-average period		3 years 1 month 6 days
Stock grants vested value | $			100
Liability for settlement | $		$ 700	$ 100
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost, net of forecasted forfeitures | $		$ 900
2004 Stock Option Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		0
Options to purchase shares, outstanding		1,131,570
2007 Stock Appreciation Grants Plan [Member] | Stock Appreciation Units (SARs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares outstanding		342,316
Vested (in shares)		17,142
2010 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		323,493
Shares outstanding		3,480,080
Awards expiration period from date of grant		10 years
Maximum aggregate number of shares of common stock that may be issued		8,000,000			865,420
Number of shares of common stock outstanding increase percentage		3.50%
2010 Equity Incentive Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price, percentage of fair value of common stock on grant date		100.00%
Options vesting period		3 years
2010 Equity Incentive Plan [Member] | Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options vesting period		4 years
2010 Equity Incentive Plan [Member] | Nonqualified Stock Options [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price, percentage of fair value of common stock on grant date		85.00%
2010 ESPP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		378,503
Maximum aggregate number of shares of common stock that may be issued		600,000			342,568
Number of shares of common stock outstanding increase percentage		3.50%
Offering period		12 months
Issuance of common stock under employee stock purchase plan (in shares)		599,879
2011 Inducement Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future grant		381,558
Shares outstanding		396,147
Exercise price, percentage of fair value of common stock on grant date		100.00%
Awards expiration period from date of grant		10 years
Maximum aggregate number of shares of common stock that may be issued		750,000
Authorized for issuance		100,000
2014 Repricing Offer [Member] | Stock Appreciation Units (SARs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued under repricing offer	87,354
2014 Repricing Offer [Member] | Stock Options and Stock Appreciation Rights [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Eligible options or stock appreciation rights date	Dec. 18, 2014		Jan. 1, 2017
Shares issued under repricing offer	2,373,692
Compensation cost, net of forecasted forfeitures | $	$ 2,600
Incremental compensation cost | $			$ 900
Exercise price per share | $ / shares			$ 3.50
Percentage of shares subject to repriced eligible stock			50.00%
Number of monthly installments | installment			12
2014 Repricing Offer [Member] | Stock Options and Stock Appreciation Rights [Member] | 60th Day Prior to Expiration Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of shares subject to repriced eligible stock			100.00%
2014 Repricing Offer [Member] | Employee Stock Options.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued under repricing offer	1,948,631

Stock-Based Compensation - Esti

Stock-Based Compensation - Estimated Fair Value of Certain Stock-Based Awards Using Black-Scholes-Merton Valuation Model (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Stock Options.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)	5 years 3 months 29 days	5 years 4 months 10 days	6 years 5 months 27 days
Weighted-average volatility	60.00%	62.00%	74.00%
Risk-free interest rate Minimum	1.37%	1.62%	1.08%
Risk-free interest rate Maximum	1.85%	2.00%	1.86%
Stock Appreciation Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)	3 years 6 months 15 days	2 years 4 months 2 days	1 year 10 months 24 days
Weighted-average volatility	62.00%	56.00%	58.00%
Risk-free interest rate Minimum	0.25%	0.13%	0.10%
Risk-free interest rate Maximum	1.57%	1.07%	0.63%
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)	8 months 9 days	7 months 24 days	8 months 23 days
Weighted-average volatility	58.00%	54.00%	48.00%
Risk-free interest rate Minimum	0.03%	0.05%	0.09%
Risk-free interest rate Maximum	0.14%	0.13%	0.16%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 7,763	$ 6,841	$ 5,736
Cost of Goods Sold [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,335	1,148	924
Research and Development Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	2,049	2,269	2,060
Selling and Marketing Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	1,794	1,429	1,167
General and Administrative Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 2,585	$ 1,995	$ 1,585

Stock-Based Compensation - Su86

Stock-Based Compensation - Summary of Information about Stock Options Outstanding (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)$ / sharesshares
Aggregate Intrinsic Value (in Thousands)
Vested and expected to vest | $	$ 30,510
Exercisable | $	$ 5,713
Weighted Average Remaining Contractual Term (Years)
Vested and expected to vest	6 years 7 months 2 days
Exercisable	6 years 8 months 16 days
Weighted Average Exercise Price
Vested and expected to vest | $ / shares	$ 4.25
Exercisable | $ / shares	$ 4.17
Number of Shares
Vested and expected to vest | shares	4,609,563
Exercisable | shares	849,680

Stock-Based Compensation - Su87

Stock-Based Compensation - Summary of Stock Option and Restricted Stock Unit Activity (Details) - $ / shares	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Weighted Average Exercise Price
Beginning Balance		$ 4.07
Granted		6.65
Exercised/Converted		3.87
Cancelled/Forfeited		4.76
Ending Balance		$ 4.34	$ 4.07
Number of Shares
Beginning Balance		4,899,713
Granted		550,380
Exercised/Converted	(895,655)	(304,385)
Cancelled/Forfeited		(137,911)
Ending Balance		5,007,797	4,899,713
Shares Available for Grant
Beginning Balance		895,311
Authorized for issuance		1,246,325
Granted		(1,699,714)
Cancelled/Forfeited		263,129
Ending Balance		705,051	895,311
Restricted stock units
Weighted Average Grant Date Fair Value
Beginning Balance		$ 6.19
Granted		7.46	$ 4.54	$ 6.96
Exercised/Converted		6.06
Cancelled/Forfeited		5.89
Ending Balance		$ 7.46	$ 6.19
Number of Units
Beginning Balance		655,729
Granted		1,149,334
Exercised/Converted		(557,828)
Cancelled/Forfeited		(33,549)
Ending Balance		1,213,686	655,729

Stock-Based Compensation - Su88

Stock-Based Compensation - Summary of Information about Restricted Stock Units Outstanding (Details) - Restricted stock units $ in Thousands	12 Months Ended
	Dec. 31, 2015USD ($)shares
Aggregate Intrinsic Value
Vested and expected to vest | $	$ 11,670
Weighted Average Remaining Contractual Term (Years)
Vested and expected to vest	1 year 7 months 28 days
Number of Shares
Vested and expected to vest | shares	1,074,552

Stock-Based Compensation - Su89

Stock-Based Compensation - Summary of Company's Stock Appreciation Unit Activity (Details) - $ / shares	3 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2015
Number of Units
Beginning Balance		4,899,713
Exercised/Converted	(895,655)	(304,385)
Cancelled/Forfeited		(137,911)
Ending Balance		5,007,797
Weighted-Average Exercise Price
Beginning Balance		$ 4.07
Exercised/Converted		3.87
Cancelled/Forfeited		4.76
Ending Balance		$ 4.34
Stock Appreciation Units (SARs) [Member]
Number of Units
Beginning Balance		375,833
Exercised/Converted		(24,707)
Cancelled/Forfeited		(8,810)
Ending Balance		342,316
Weighted-Average Exercise Price
Beginning Balance		$ 4.85
Exercised/Converted		4.36
Cancelled/Forfeited		6.39
Ending Balance		$ 4.85

Income taxes - Income (Loss) be

Income taxes - Income (Loss) before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income taxes
U.S. operations	$ (7,212)	$ (30,046)	$ (39,618)
Non-U.S. operations	13,984	12,846	6,483
Income (loss) before income taxes	$ 6,772	$ (17,200)	$ (33,135)

Income taxes - Components of Pr

Income taxes - Components of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current
Federal	$ (48)	$ (71)	$ 7
State	(8)	(18)	(11)
Foreign	(3,725)	(1,218)	(1,658)
Provision for income tax, current	(3,781)	(1,307)	(1,662)
Deferred
Federal	(22)
Foreign	699	(1,212)	458
Total provision for income taxes from continuing operations	$ (3,104)	$ (2,519)	$ (1,204)

Income taxes - Difference in Pr

Income taxes - Difference in Provision for Income Taxes from Amount Obtained by Applying U.S. Federal Statutory Rate (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income taxes
Federal statutory rate	35.00%	35.00%	35.00%
Tax at federal statutory rate	$ (2,378)	$ 5,969	$ 11,597
State taxes, net of federal benefit	(8)	(18)	1,058
Subpart F income	(66)	(18,986)
Nondeductible expenses	(135)	(125)	(260)
Stock-based compensation	(465)	(542)	(385)
Change in valuation allowance	(958)	(724)	(13,042)
Research and development	1,017	539	1,077
Foreign rate differences	(844)	1,246	(2,129)
Earn out adjustment not taxable			(359)
Escrow settlement		1,360
Income Tax Reconciliation Tax Credits Foreign	30	9,208
Change in prior year deferred balances	417	(308)	1,756
Acquisition-related costs			(391)
Other	286	(138)	(126)
Total provision for income taxes from continuing operations	$ (3,104)	$ (2,519)	$ (1,204)

Income taxes - Components of De

Income taxes - Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Net operating loss carryforwards	$ 60,063	$ 67,898
Federal and state credits	21,752	19,443
Reserves, accruals and other	10,325	8,842
Fixed assets and intangibles	1,459	1,161
Total deferred tax assets	93,599	97,344
Valuation allowance	(88,940)	(91,278)
Total deferred tax assets, net of valuation allowance	4,659	6,066
Deferred tax liabilities:
Acquired intangibles	(3,878)	(5,930)
Net deferred tax assets	781	136
Reported as:
Current deferred tax assets, included within prepaid expenses and other current assets		1,954
Long term deferred tax assets, included within other long-term assets	869	181
Current deferred income tax liabilities		(181)
Deferred income tax liabilities	(88)	(1,818)
Net deferred tax assets	$ 781	$ 136

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Decrease in net valuation allowance	$ 2,300	$ (200)
Income tax statutory rate	35.00%	35.00%	35.00%
Gross unrecognized tax benefits	$ 20,686	$ 18,372	$ 16,452	$ 11,993
Unrecognized tax benefits affecting effective tax rate if recognized		200
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	$ 0
Open tax year	2,010
Federal [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 207,000
Research credit	$ 6,300
Net operating loss carryforwards, expiration date	Dec. 31, 2018
Tax credit expiration date	Dec. 31, 2018
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 69,200
Research credit	13,100
Foreign Country [Member]
Income Taxes [Line Items]
Research credit	$ 10,200
Tax credit expiration date	Dec. 31, 2022
Benefits realized from reduced tax rate	$ 900	$ 500	$ 200
Foreign Country [Member] | Subsidiaries [Member]
Income Taxes [Line Items]
Income tax statutory rate	25.00%
Effective income tax rate	15.00%
Preferential granted effective income tax rate, Termination Date	2,016
Employee Stock Options [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	$ 2,700

Income taxes - Reconciliation o

Income taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income taxes
Beginning Balance	$ 18,372	$ 16,452	$ 11,993
Gross increases for tax positions of prior years			155
Gross increases for tax positions of current year	2,314	2,090	4,361
Reductions resulting from lapse of applicable statute of limitations		(170)	(57)
Ending Balance	$ 20,686	$ 18,372	$ 16,452

Segment and Geographic Inform96

Segment and Geographic Information - Additional Information (Details) - segment	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment and geographic information
Number of reportable segments	1	1	1

Segment and Georgraphic Informa

Segment and Georgraphic Information - Revenue and Long-Lived Assets By Geographical Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Revenue	$ 89,123	$ 83,560	$ 85,372	$ 81,384	$ 78,982	$ 81,576	$ 77,451	$ 68,168	$ 339,439	$ 306,177	$ 282,242
Property, plant and equipment, net	62,618				57,657				62,618	57,657
High Speed Products
Segment Reporting Information [Line Items]
Revenue									195,831	129,595	107,705
Network Products And Solutions
Segment Reporting Information [Line Items]
Revenue									143,608	176,582	174,537
China
Segment Reporting Information [Line Items]
Revenue									182,504	161,509	122,387
Property, plant and equipment, net	24,334				28,807				24,334	28,807
United States
Segment Reporting Information [Line Items]
Revenue									77,867	56,603	45,036
Property, plant and equipment, net	19,308				14,877				19,308	14,877
Japan
Segment Reporting Information [Line Items]
Revenue									12,713	16,261	25,451
Property, plant and equipment, net	15,603				13,150				15,603	13,150
Rest of World
Segment Reporting Information [Line Items]
Revenue									66,355	71,804	$ 89,368
Property, plant and equipment, net	$ 3,373				$ 823				$ 3,373	$ 823

Summary of Quarterly Financial

Summary of Quarterly Financial Information (unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Data
Net revenues	$ 89,123	$ 83,560	$ 85,372	$ 81,384	$ 78,982	$ 81,576	$ 77,451	$ 68,168	$ 339,439	$ 306,177	$ 282,242
Gross profit	25,110	23,772	26,146	24,053	22,686	20,064	14,568	13,800	99,081	71,118	65,173
Net income	$ 399	$ 1,378	$ 1,791	$ 100	$ 1,585	$ (1,937)	$ (6,779)	$ (12,588)	$ 3,668	$ (19,719)	$ (34,339)
Basic and diluted net income per share	$ 0.01	$ 0.03	$ 0.05		$ 0.05	$ (0.06)	$ (0.21)	$ (0.40)
Weighted average shares used to compute basic net income (loss) per share	40,739	40,367	35,684	32,780	32,640	32,383	31,790	31,610	37,421	32,109	31,000
Weighted averages shares used to compute diluted net (loss) income per share	42,668	42,217	37,294	33,031	32,710	32,383	31,790	31,610	38,686	32,109	31,000

Subsequent Event (Details)

Subsequent Event (Details) $ in Millions	1 Months Ended
	Jan. 31, 2016USD ($)
Comerica [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Repayments of Lines of Credit	$ 23.8