Neophotonics (NPTN) 10-Q 6 Nov 15 2015 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2015	Oct. 31, 2015
Document Document And Entity Information [Abstract]
Entity Registrant Name	NEOPHOTONICS CORP
Entity Central Index Key	1,227,025
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2015
Trading Symbol	NPTN
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		40,523,326
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q3

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 77,250	$ 43,035
Short-term investments	23,302
Restricted cash and investments	3,062	5,504
Accounts receivable, net of allowance for doubtful accounts	77,830	77,597
Inventories	70,747	57,347
Prepaid expenses and other current assets	10,723	15,540
Total current assets	262,914	199,023
Property, plant and equipment, net	62,470	57,657
Restricted cash and investments, non-current		15,750
Purchased intangible assets, net	11,169	10,263
Goodwill	1,115
Other long-term assets	3,743	3,591
Total assets	341,411	286,284
Current liabilities:
Accounts payable	54,465	48,949
Notes payable and short-term borrowing	10,196	22,771
Current portion of long-term debt	24,563	2,445
Accrued and other current liabilities	21,406	22,728
Total current liabilities	110,630	96,893
Long-term debt, net of current portion	11,005	20,891
Deferred income tax liabilities	1,808	1,818
Other noncurrent liabilities	7,547	7,226
Total liabilities	$ 130,990	$ 126,828
Commitments and contingencies (Note 10)
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 September 30, 2015, 40,478 shares issued and outstanding; at December 31, 2014, 32,752 shares issued and outstanding	$ 101	$ 82
Additional paid-in capital	507,969	456,189
Accumulated other comprehensive income	1,223	5,326
Accumulated deficit	(298,872)	(302,141)
Total stockholders' equity	210,421	159,456
Total liabilities and stockholders' equity	$ 341,411	$ 286,284

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Sep. 30, 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	40,478	32,752
Common stock, shares outstanding	40,478	32,752

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Revenue	$ 83,560	$ 81,576	$ 250,316	$ 227,195
Cost of goods sold	59,788	61,512	176,345	178,763
Gross profit	23,772	20,064	73,971	48,432
Operating expenses:
Research and development	10,763	11,842	32,702	35,983
Sales and marketing	3,789	3,075	11,439	10,057
General and administrative	7,384	6,712	22,999	23,892
Amortization of purchased intangible assets	447	378	1,344	1,136
Asset impairment charge	368		368
Acquisition-related costs	180		467
Restructuring charges	18	504	44	504
Escrow settlement gain				(3,886)
Total operating expenses	22,949	22,511	69,363	67,686
Income (loss) from operations	823	(2,447)	4,608	(19,254)
Interest income	31	52	84	155
Interest expense	(171)	(375)	(1,133)	(937)
Other income, net	1,852	1,735	2,408	493
Total interest and other income (expense), net	1,712	1,412	1,359	(289)
Income (loss) before income taxes	2,535	(1,035)	5,967	(19,543)
Provision for income taxes	(1,157)	(902)	(2,698)	(1,761)
Net income (loss)	$ 1,378	$ (1,937)	$ 3,269	$ (21,304)
Basic net income (loss) per share	$ 0.03	$ (0.06)	$ 0.09	$ (0.67)
Diluted net income (loss) per share	$ 0.03	$ (0.06)	$ 0.09	$ (0.67)
Weighted average shares used to compute basic net income (loss) per share	40,367	32,383	36,303	31,930
Weighted average shares used to compute diluted net income (loss) per share	42,217	32,383	37,537	31,930

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 1,378	$ (1,937)	$ 3,269	$ (21,304)
Foreign currency translation adjustments, net of zero tax	(4,687)	(2,281)	(4,098)	(3,118)
Defined benefit pension plans adjustment, net of tax of $73				118
Unrealized gains (losses) on available-for-sale securities, net of zero tax	(1)		(5)	3
Comprehensive loss	$ (3,310)	$ (4,218)	$ (834)	$ (24,301)

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Comprehensive Income ( Loss) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0	$ 0
Defined benefit pension plans adjustment, tax				73
Unrealized (loss) gains on investments, tax	$ 0	$ 0	$ 0	$ 0

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash flows from operating activities
Net income (loss)	$ 3,269	$ (21,304)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	17,511	17,492
Stock-based compensation expense	5,418	4,812
Deferred taxes	719	76
Investment and debt related amortization	248	197
(Gain) loss on disposal of property and equipment	(22)	131
Adjustment to fair value of penalty payment derivative	(141)	(289)
Allowance for doubtful accounts	628	287
Asset Impairment Charges	368
Foreign currency remeasurement and other, net	(1,867)	(1,233)
Change in assets and liabilities, net of effects of acquisitions:
Accounts receivable	8,035	(14,781)
Inventories	(13,415)	5,224
Prepaid expenses and other assets	1,962	(4,270)
Accounts payable	(1,718)	4,974
Accrued and other liabilities	117	(2,744)
Net cash provided by (used in) operating activities	21,112	(11,428)
Cash flows from investing activities
Purchase of property, plant and equipment	(11,051)	(9,124)
Proceeds from sale of property, plant and equipment and other assets	200	8
Purchase of marketable securities	(28,936)	(9,654)
Proceeds from sale of marketable securities	12,938	9,634
Proceeds from maturity of securities	1,000	9,448
Decrease (increase) in restricted cash	9,784	(12,251)
Net cash used in investing activities	(16,065)	(11,939)
Cash flows from financing activities
Proceeds from public stock offering, net of offering costs	45,646
Proceeds from exercise of stock options and issuance of stock under ESPP	1,186	1,992
Tax withholding on restricted stock units	(688)	(370)
Proceeds from bank loans	56,512	8,105
Repayment of bank and acquisition-related loans	(70,162)	(8,651)
Proceeds from issuance of notes payable	16,999	18,822
Repayment of notes payable	(20,072)	(15,851)
Payment of acquisition-related contingent consideration		(1,985)
Net cash provided by financing activities	29,421	2,062
Effect of exchange rates on cash and cash equivalents	(253)	(527)
Net increase (decrease) in cash and cash equivalents	34,215	(21,832)
Cash and cash equivalents at the beginning of the period	43,035	57,101
Cash and cash equivalents at the end of the period	77,250	35,269
Supplemental disclosure of noncash investing and financing activities:
Modification of bank loan	15,786
Issuance of note to seller of acquired business	15,482
Transfer of restricted investments to short-term investments	8,296
Transfer of short-term investments to restricted investments		8,295
Changes in unpaid property, plant and equipment	$ (768)	$ 302

Basis of presentation and signi

Basis of presentation and significant accounting policies	9 Months Ended
	Sep. 30, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Significant Accounting Policies	Note 1. Basis of presentation and significant accounting policies Basis of Presentation and Consolidation The condensed consolidated financial statements of NeoPhotonics Corporation (“NeoPhotonics” or the “Company”) as of September 30, 2015 and for the three and nine months ended September 30, 2015 and 2014, have been prepared in accordance with the instructions on Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). In accordance with those rules and regulations, the Company has omitted certain information and notes normally provided in the Company’s annual consolidated financial statements. In the opinion of management, the condensed consolidated financial statements contain all adjustments, consisting only of normal recurring items, except as otherwise noted, necessary for the fair presentation of the Company’s financial position and results of operations for the interim periods. The year-end condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. generally accepted accounting principles (“U.S. GAAP”). These condensed consolidated financial statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014. The results of operations for the three and nine months ended September 30, 2015 are not necessarily indicative of the results expected for the entire fiscal year. All significant intercompany accounts and transactions have been eliminated. 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., China 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. Concentration In the three months ended September 30, 2015, Huawei Technologies Co. Ltd. and their affiliate HiSilicon Technologies (together with Huawei Technologies Co. Ltd., “Huawei”) and Ciena Corporation (“Ciena”) accounted for approximately 41% and 26% of the Company’s total revenue, respectively, and the Company’s top ten customers represented approximately 92% of the Company’s total revenue. In the three months ended September 30, 2014, Huawei and Ciena each accounted for approximately 35% and 17% of the Company’s total revenue, respectively, and the top ten customers represented approximately 88% of its total revenue. In the nine months ended September 30, 2015, Huawei and Ciena accounted for approximately 40% and 24% of the Company’s total revenue, respectively, and the Company’s top ten customers represented approximately 91% of its total revenue. In the nine months ended September 30, 2014, Huawei, Ciena and Alcatel-Lucent SA each accounted for approximately 36% , 15% and 11% of the Company’s total revenue, respectively, and the top ten customers represented approximately 88% of its total revenue. As of September 30, 2015, two customers accounted for approximately 44% and 21% of the Company’s total accounts receivable. As of December 31, 2014, two customers accounted for 45% and 10% of the Company’s total accounts receivable. Use of Estimates The preparation of financial statements in accordance with 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; valuation of excess and obsolete inventories; warranty reserves; litigation accrual and recognition of stock-based compensation, among others. Actual results could differ from these estimates. Summary of Significant Accounting Policies There have been no significant changes in the Company’s significant accounting policies in the three and nine months ended September 30, 2015, as compared to the significant accounting policies described in its Annual Report on Form 10-K for the year ended December 31, 2014. Recent accounting pronouncements In September 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update ("ASU") 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments (“ASU 2015-16”). ASU 2015-16 requires an acquirer of a business to recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. This guidance also requires acquirers to present separately on the face of the income statement, or disclose in the notes, the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. ASU 2015-16 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. The Company does not expect the adoption of this standard to have an impact on its consolidated financial statements. In July 2015, the FASB issued ASU 2015-12, Plan Accounting: Defined Benefit Pension Plans (Topic 960), Defined Contribution Pension Plans (Topic 962), Health and Welfare Benefit Plans (Topic 965): (Part I) Fully-Benefit R e sponsive Investment Contracts, (Part II) Plan Investment Disclosures, (Part III) Measurement D a te Practical Expedient (consensus of the FASB Emerging Issues Task Force (“ASU 2015-12”). ASU 2015-12 requires (1) a pension plan to use contract value as the only measure for fully benefit-responsive investment contracts, (2) simplifies and increases the effectiveness of the investment disclosure requirements for employee benefit plans, and (3) provides benefit plans with a measurement-date practical expedient similar to the practical expedient provided to employers. This ASU is effective for fiscal years beginning after December 15, 2015. E a rly adoption is permitted. The amendments in parts I and II should be applied retrospectively to all financial statements presented, while the amendments in part III should be applied prospectively. 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. E a rly adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs (“ASU 2015-03”). ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. In August 2015, the FASB issued ASU 2015-15, I n terest-Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements-Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EIFT Meeting (“ASU 2015-15”). ASU 2015-15 clarifies the SEC would not object an entity deferring and presenting debt issuance costs associated with line-of-credit arrangements as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In April 2015, the FASB issued ASU 2015-05, Intangibles-Goodwill and Other-Internal Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement (“ASU 2015-05”) to provide guidance to a customer’s accounting for cloud computing costs. Under ASC 2015-05, a customer must determine whether a cloud computing arrangement contains a software license and account for an arrangement that contains a software license element consistent with the accounting for other software licenses. An arrangement would contain a software license element if (a) the customer has the contractual right to take possession of the software at any time during the hosting period without significant penalty and (b) it is feasible for the customer to either run the software on its own hardware or contract with another party unrelated to the vendor to host the software. This guidance is effective for annual and interim periods beginning after December 15, 2015, with early adoption permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In January 2015, the FASB issued ASU 2015-01, Income Statement – Extraordinary and Unusual Items: Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items (“ASU 2015-01”) , which eliminates from U.S. GAAP the concept of extraordinary items. The guidance eliminates the separate presentation of extraordinary items on the income statement, net of tax and the related earnings per share, but does not affect the requirement to disclose material items that are unusual in nature or occurring infrequently. The new standard may be applied prospectively or retrospectively and is effective for annual reporting periods beginning after December 15, 2015 and interim periods within those annual periods, with early adoption permitted. The Company does not expect the adoption of this standard to have an impact 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. In April 2014, the FASB issued ASU No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity ("ASU 2014-08") which raises the threshold for a disposal to qualify as a discontinued operation and requires new disclosures of both discontinued operations and certain other disposals that do not meet the definition of a discontinued operation. ASU 2014-08 is effective for annual periods beginning on or after December 15, 2014. The Company’s adoption of this guidance on January 1, 2015 did not impact its consolidated financial statements.

Net income (loss) per share

Net income (loss) per share	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
Net loss per share	Note 2. Net income (loss) per share The following table sets forth the computation of the basic and diluted net income (loss) per share for the periods indicated (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 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 loss per share, as their effect would have been antidilutive (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Employee stock options Restricted stock units Employee stock purchase plan — — Common stock warrants — —

Cash, cash equivalents, short-t

Cash, cash equivalents, short-term investments, and restricted cash and investments	9 Months Ended
	Sep. 30, 2015
Cash And Cash Equivalents [Abstract]
Cash, cash equivalents, short-term investments, and restricted cash and investments	Note 3. Cash, cash equivalents, 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 September 30, 2015 and December 31, 2014 (in thousands): September 30, 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 its cash equivalents, short-term investments, and restricted cash and investments in marketable securities designated as available-for-sale (in thousands): As of September 30, 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 — — — — — U.S. government securities — — — — — Commercial papers — — — — — — Variable rate demand notes — — — — — — Total $ $ $ $ $ $ $ — $ Reported within: Cash equivalents $ $ — $ — $ $ — $ — $ — $ — Short-term investments — — — — Restricted cash and investments, non-current — — — — — Total $ $ $ $ $ $ $ — $ As of September 30, 2015 and December 31, 2014, maturities of marketable securities were as follows (in thousands): September 30, December 31, 2015 2014 Less than 1 year $ $ Due in 1 to 2 years — Due in 2 to 5 years — — Due after 5 years — Total $ $ 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 may sell its investments in the future to fund future operating needs and for strategic reasons. As a result, the Company recorded all its marketable securities in short-term investments as of September 30 , 2015 and December 31, 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 are secured by a pledged liquidity source. While they are classified as short-term investments, the put option allows the VRDNs to be liquidated at par on a seven-day settlement basis. Realized gains and losses on the sale of marketable securities during the three and nine months ended September 30 , 2015 and 2014 were immaterial. The Company did not recognize any impairment losses on its marketable securities during the three and nine months ended September 30 , 2015 or 2014. As of September 30 , 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 disclosures

Fair value disclosures	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
Fair value disclosures	Note 4. Fair value disclosures 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 September 30, 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 $ $ — $ — $ $ $ — $ — $ Time deposits — — — — — — — — Money market accounts — — — — — — Corporate bonds — — — — Government-sponsored enterprise obligations — — — — — — U.S. government securities — — — — — — Commercial papers — — — — — — 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 September 30, 2015. The assets held by the Rabbi Trust are substantially in the form of exchange traded mutual funds and are included in the Company’s other long-term assets on its condensed consolidated balance sheets as of September 30, 2015 and December 31, 2014. The following table presents the Company's liabilities that are measured at fair value on a recurring basis (in thousands): As of September 30, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Penalty payment derivative (Note 10) $ — $ — $ $ $ — $ — $ $ Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis There were no assets or liabilities measured at fair value on a nonrecurring basis as of September 30, 2015 or December 31, 2014. Assets and Liabilities Not Measured at Fair Value The carrying values of cash and cash equivalents, 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. The fair value of the Company’s variable rate bank borrowings was not materially different than its carrying value as of September 30, 2015 and December 31, 2014 as the interest rates approximated rates available to the Company and the fair value of the Company’s acquisition-related debt at December 31, 2014 approximated its carrying value.

Business combination

Business combination	9 Months Ended
	Sep. 30, 2015
Business combination [Abstract]
Business Combinations	Note 5. Business combination 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 this acquisition, the Company aims to strengthen its narrow line width tunable laser product portfolio. 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 condensed consolidated statement of operations. The Company’s preliminary 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 are 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 is 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 and accounts payable, as the Company is in the process of obtaining further information. As a result, during the preliminary measurement period, which may be up to one year from the acquisition date, the Company records adjustments to the assets acquired and liabilities assumed with the corresponding offset to goodwill. As of September 30, 2015, the Company recorded $ 1.1 million in goodwill, which represented the excess of the purchase price over the aggregate net estimated fair values of the assets acquired and liabilities assumed in the acquisition. Subsequent to the initial allocation of the assets acquired and liabilities assumed, the Company reduced the acquired net accounts receivable by $0.2 million, increased the acquired net inventories by $0.1 million, reduced the assumed sales tax accrual by $0.1 million, increased the acquired prepaid expenses and other current assets by an immaterial amount, and increased goodwill by a corresponding net amount. 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 three and nine months ended September 30, 2015 and 2014 as though the companies had been combined as of the beginning of 2014. In the three and nine months ended September 30, 2015, revenue related to products acquired from EMCORE was $13.2 million and $39.5 million, respectively. The pro forma financial information reflects adjustments related to transactions costs of $0.3 million in the nine months September 30, 2015 and 2014, as well as immaterial employee expense in the nine months ended September 30, 2015. Incremental intangible amortization, inventory and depreciation adjustments were also added to the 2014 periods. There were no sales between the business acquired from EMCORE and the Company in the three and nine months ended September 30, 2015 and 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): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Revenue $ $ $ $ Net income (loss) $ $ $ $ Basic net income (loss) per share $ $ $ $ Diluted net income (loss) per share $ $ $ $

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2015
Balance Sheet Components [Abstract]
Balance Sheet Components	Note 6. Balance sheet components Restricted cash and investments Restricted cash and investments consist of the following (See Note 8) (in thousands): September 30, 2015 December 31, 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 consists of the following (in thousands): September 30, 2015 December 31, 2014 Accounts receivable $ $ Trade notes receivable Allowance for doubtful accounts $ $ Inventories, net Inventories, net consist of the following (in thousands): September 30, 2015 December 31, 2014 Raw materials $ $ Work in process Finished goods $ $ (1) Finished goods inventory at customer vendor managed inventory locations was $13.7 million and $6.4 million as of September 30, 2015 and December 31, 2014, respectively. Purchased intangible assets Purchased intangible assets consist of the following (in thousands): September 30, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Assets Amortization Assets Assets Amortization Assets Technology and patents $ $ $ $ $ $ Customer relationships Leasehold interest Non-compete agreements — — $ $ $ $ $ $ Amortization expense relating to technology and patents and the leasehold interest intangible assets is included within cost of goods sold, and customer relationships within operating expenses. The following table presents details of the amortization expense of the Company’s purchased intangible assets as reported in the condensed consolidated statements of operations (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Cost of goods sold $ $ $ $ Operating expenses Total $ $ $ $ The estimated future amortization expense of purchased intangible assets as of September 30, 2015, is as follows (in thousands): 2015 (remaining three months) $ 2016 2017 2018 2019 Thereafter $ Accrued and other current liabilities Accrued and other current liabilities consist of the following (in thousands): September 30, 2015 December 31, 2014 Employee-related $ $ Accrued warranty Penalty payment derivative Deferred income tax liabilities Other accrued expenses $ $ Warranty Accrual The table below summarizes the movement in the warranty accrual , which is included in accrued and other current liabilities (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Beginning balance $ $ $ $ Warranty accruals Settlements Ending balance $ $ $ $ Other noncurrent liabilities Other noncurrent liabilities consist of the following (in thousands): September 30, 2015 December 31, 2014 Pension and other employee-related $ $ Other $ $

Restructuring

Restructuring	9 Months Ended
	Sep. 30, 2015
Restructuring And Related Activities [Abstract]
Restructuring	Note 7. 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. Restructuring ch arges recorded in the nine months ended September 30, 2015 was $0.2 million and was included within cost of goods sold and operating expenses. The remaining restructuring liability is expected to be paid through October 2015. The following table summarizes activity associated with restructuring obligations during the nine months ended September 30, 2015 (in thousands): Workforce Reduction Facilities Total Restructuring obligations, December 31, 2014 $ $ $ Restructuring costs incurred — Cash payments Restructuring obligations, September 30, 2015 $ — $ $

Debt

Debt	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
Debt	Note 8. Debt The table below summarizes the carrying amount and weighted average interest rate of the Company’s debt (in thousands, except percentages): September 30, 2015 December 31, 2014 Weighted Weighted Average Average Carrying Interest Carrying Interest Amount Rate Amount Rate Notes payable $ — $ — 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 non-interest 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. In June 2015, the Company’s subsidiary i n China renewed its short-term line of credit facility with a banking institution to an expiration date in June 2016 . Under the renewed agreement, RMB 120.0 million ( $18.9 million) can be used for short-term loans, which bears interest at varying rates, or up to approximately RMB 171.4 million ( $26.9 million) can be used for bank acceptance drafts (with a 30% compensating balance requirement). In September 2015, the Company’s China subsidiary renewed its second short-term line of credit facility with a banking institution, under which RMB 133.0 million ( $20.9 million) can be used for short-term loan or up to approximately RMB 190.0 million ( $29.9 million ) can be used for bank acceptance drafts (with a 30% compensating balance requirement). This line of credit facility expires in September 2016 . As of September 30, 2015 and December 31, 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 $10.2 million and $12.8 million, respectively. As of September 30, 2015 and December 31, 2014, compensating balances relating to these bank acceptance drafts issued to suppliers and the Company’s subsidiaries totaled $3.1 million and $3.8 million, respectively. Compensating balances are classified as restricted cash and investments on the Company’s condensed consolidated balance sheets. Short-term borrowing In October 2014, the Company’s subsidiary in China entered into a short-term advance financing agreement, under one of its line of credit facilities, to borrow $5.0 million against export sales to its parent company. This financing agreement bore interest at 4.02% per annum. Interest and the principal were due and repaid in full in April 2015 . In November 2014, the Company’s subsidiary in China entered into a second short-term advance financing agreement, under one of its line of credit facilities, to borrow $5.0 million against export sales to its parent company. This financing agreement bore interest at 2.33% per annum and service fees at 1.00% per annum. Interest, service fees and the principal were due and repaid in full in May 2015 . On April 21, 2015, the Company’s China subsidiary executed a $5.0 million advance financing agreement with one of its line of credit 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 on October 8, 2015 . The Company repaid the loan in September 2015. Acquisition-related In connection with the acquisition of NeoPhotonics Semiconductor on March 29, 2013, the Company was obligated to pay 1,050 million Japanese Yen (“JPY”) in three equal installments on the first, second and third 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 as of 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. As part of the purchase consideration to acquire the tunable laser products of EMCORE in January 2015 (See Note 5), 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. Bank borrowings 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% . Base rate is based on 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 and is secured by substantially all of the Company’s U.S. assets, other than intellectual property assets. The Company repaid the remaining Comerica term loan balance and borrowed $15.8 million under the amended revolving credit facility in March 2015. As of September 30, 2015, the outstanding balance under the revolving credit facility was $23.8 million, which was repaid in October 2015. The components of the Comerica credit facilities are as follows: — A $30.0 million revolving credit facility under which there was $23.8 million outstanding at September 30, 2015 and no outstanding borrowing as of December 31, 2014, subject to covenant requirements. Amounts borrowed, if any, 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 September 30, 2015 the rate on the LIBOR option was 2.95% . — 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 September 30, 2014, which noncompliance was effectively waived in the amendment described below. During 2014, the Company executed an amendment to the credit agreement 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 a modified EBITDA and certain liquidity covenants. As of September 30, 2015, the Company was in compliance with the related covenants. As of September 30 , 2015 and December 31, 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 condensed consolidated balance sheet (see Note 6). 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 September 30, 2015, outstanding principal balance under the Mitsubishi Bank Loans was approximat ely 1.4 billion JPY (approximately $12.0 million) and the Company was in compliance with the related covenants. At September 30, 2015, maturities of long-term debt were as follows (in thousands): 2015 (remaining three months) $ 2016 2017 2018 2019 Thereafter $

Japan pension plans

Japan pension plans	9 Months Ended
	Sep. 30, 2015
Compensation And Retirement Disclosure [Abstract]
Japan Pension Plans	Note 9. Japan pension plans In connection with its acquisition of NeoPhotonics Semiconductor on March 29, 2013 from LAPIS Semiconductor Co., Ltd. (“LAPIS”), 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, in accordance with the acquisition agreements, the seller transferred approximately $2.0 million into the newly formed DCP which is 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. As a result of these changes to the DBCPP and RAP, the Company recorded a curtailment gain of $0.1 million in the quarter ended March 31, 2014. The pension liability at September 30 , 2015 and December 31, 2014 was $5.1 million of which $0.1 million was recorded in accrued and other current liabilities and the remainder in other noncurrent liabilities on the Company’s condensed consolidated balance sheet. The Company contributed $15,000 to the DBCPP from January 1, 2014 to February 28, 2014. Because the DBCPP transitioned to the DCP on that date, no further contributions to the DBCPP are required. Net periodic pension cost associated with these plans included the following components (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Service cost $ — $ — $ — $ Interest cost — — — Amortization — — — Net periodic pension costs $ — $ — $ — $

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 10. Commitments and contingencies 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 is appealing this verdict, 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 net litigation expense relating to this matter in March 2015. There was no change in such accrual in the second and third quarters of 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 September 30 , 2015, the Company did not have any material indemnification claims that were probable or reasonably possible. Leases The Company leases various facilities under non-cancelable operating leases expiring through 2023 . As of September 30, 2015, future minimum payments under these operating leases totaled $6.2 million and future minimum sublease receipts was approximately $1.6 million. Rent expense was $0.5 million and $1.7 million in the three and nine months ended September 30, 2015, respectively, and $0.5 million and $1.6 million in the three and nine months ended September 30, 2014, respectively. 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 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 certain of the Investment Commitments are not 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 $1.5 million at the end of 2016 or 2019, respectively . 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, 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 expense, net. The estimated fair value of this derivative was $0.4 million and $0.5 million as of September 30, 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 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 11). 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 11), 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, for a period of 180 days from May 21, 2015.

Stockholders' equity

Stockholders' equity	9 Months Ended
	Sep. 30, 2015
Stockholders Equity [Abstract]
Stockholders' Equity	Note 11. Stockholders’ equity Common Stock As of September 30, 2015, the Company had reserved 7,009,303 common stock shares for issuance under its stock option plans and 678,438 common stock shares 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 10). 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 Income, Net of Tax The components of accumulated other comprehensive income, net of related taxes, were as follows (in thousands): September 30, 2015 December 31, 2014 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 three and nine months ended September 30 , 2015 and 2014 for realized gains or losses on available-for-sale securities. Accumulated Deficit Approximately $7.1 million of the Company’s accumulated deficit at December 31, 2014 was subject to restriction due to the fact that the Company’s subsidiaries in China are required to 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	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	Note 12. Stock-based compensation The following table summarizes the stock-based compensation expense recognized in the three and nine months ended September 30, 2015 and 2014 (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Cost of goods sold $ $ $ $ Research and development Sales and marketing General and administrative $ $ $ $ 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: Three Months Ended September 30, Nine Months Ended September 30, Stock options 2015 2014 2015 2014 Weighted-average expected term (years) 5.6 5.8 5.4 5.5 Weighted-average volatility 63% 66% 64% 68% Risk-free interest rate 1.63% - 1.85% 1.62% - 1.88% 1.37% – 1.85% 1.62% – 1.88% Expected dividends — — — — Stock appreciation units Weighted-average expected term (years) 3.5 2.5 3.6 2.5 Weighted-average volatility 60% 54% 62% 56% Risk-free interest rate 0.28% – 1.38% 0.47% – 0.88% 0.25% – 1.57% 0.13% – 0.90% Expected dividends — — — — ESPP Weighted-average expected term (years) — — 0.7 0.7 Weighted-average volatility — — 58% 54% Risk-free interest rate — — 0.03% - 0.14% 0.05% – 0.13% Expected dividends — — — — Stock Options and Restricted Stock Units (RSUs) The following table summarizes the Company’s stock option and RSU activity during the nine months ended September 30, 2015 : Stock Options Restricted Stock Units Weighted Weighted Average Average Number of Exercise Number of Grant Date Shares Price Units Fair Value Balance at December 31, 2014 $ $ Granted $ $ Exercised/Converted $ $ Cancelled/Forfeited $ $ Balance at September 30, 2015 $ $ Stock appreciation units (“SAUs”) SAUs are liability classified share-based awards. The Company did not grant any SAUs during the three and nine months ended September 30, 2015 or 2014. As of September 30, 2015 and December 31, 2014, there were 352,664 and 375,833 SAUs outstanding. Outstanding SAUs were re-measured each reporting period at fair value. Employee Stock Purchase Plan (“ESPP”) As of September 30, 2015 there was $41, 000 of unrecognized stock-based compensation expense for stock purchase rights that will be recognized over the remaining offering period, through November 2015.

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Note 13. Income taxes Three Months Ended Nine Months Ended September 30, September 30, (in thousands) 2015 2014 2015 2014 Provision for income taxes $ $ $ $ The Company’s income tax provision in the three and nine months ended September 30, 2015 and 2014 was primarily related to income taxes of the Company’s non-U.S. operations. The Company conducts its business globally and its operating income is subject to varying rates of tax in the United States, China and Japan. Consequently, the Company’s effective tax rate is dependent upon the geographic distribution of its earnings or losses and the tax laws and regulations in each geographical region. Historically, the Company has experienced net losses in the United States and in the short term, expects this trend to continue. One of the Company’s subsidiaries in China has historically qualified for a preferential 15% tax rate available for high technology enterprises as opposed to the statutory 25% tax rate. In November 2014, the Company received the final approval for the preferential tax rate for 2014 to 2016. Due to historic losses in the U.S., the Company has a full valuation allowance on its U.S. federal and state deferred tax assets. Management continues to evaluate the realizability of deferred tax assets and the related valuation allowance. If management's assessment of the deferred tax assets or the corresponding valuation allowance were to change, the Company would record the related adjustment to income during the period in which management makes the determination. As of September 30, 2015, there were no material changes to either the nature or the amounts of the uncertain tax positions previously determined for the year ended December 31, 2014.

Subsequent event

Subsequent event	9 Months Ended
	Sep. 30, 2015
Subsequent Event [Abstract]
Subsequent Event	Note 14. Subsequent events Subsequent events, through the filing of this report, included the following: Acquisition of EigenLight Corporation On November 2, 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 will account for the acquisition as a business combination upon closing. The initial purchase accounting for this transaction was not yet complete at the filing of this report.

Basis of presentation and sig22

Basis of presentation and significant accounting policies (Policies)	9 Months Ended
	Sep. 30, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The condensed consolidated financial statements of NeoPhotonics Corporation (“NeoPhotonics” or the “Company”) as of September 30, 2015 and for the three and nine months ended September 30, 2015 and 2014, have been prepared in accordance with the instructions on Form 10-Q pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). In accordance with those rules and regulations, the Company has omitted certain information and notes normally provided in the Company’s annual consolidated financial statements. In the opinion of management, the condensed consolidated financial statements contain all adjustments, consisting only of normal recurring items, except as otherwise noted, necessary for the fair presentation of the Company’s financial position and results of operations for the interim periods. The year-end condensed consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. generally accepted accounting principles (“U.S. GAAP”). These condensed consolidated financial statements should be read in conjunction with the Consolidated Financial Statements and Notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014. The results of operations for the three and nine months ended September 30, 2015 are not necessarily indicative of the results expected for the entire fiscal year. All significant intercompany accounts and transactions have been eliminated. 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., China 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.
Concentration	Concentration In the three months ended September 30, 2015, Huawei Technologies Co. Ltd. and their affiliate HiSilicon Technologies (together with Huawei Technologies Co. Ltd., “Huawei”) and Ciena Corporation (“Ciena”) accounted for approximately 41% and 26% of the Company’s total revenue, respectively, and the Company’s top ten customers represented approximately 92% of the Company’s total revenue. In the three months ended September 30, 2014, Huawei and Ciena each accounted for approximately 35% and 17% of the Company’s total revenue, respectively, and the top ten customers represented approximately 88% of its total revenue. In the nine months ended September 30, 2015, Huawei and Ciena accounted for approximately 40% and 24% of the Company’s total revenue, respectively, and the Company’s top ten customers represented approximately 91% of its total revenue. In the nine months ended September 30, 2014, Huawei, Ciena and Alcatel-Lucent SA each accounted for approximately 36% , 15% and 11% of the Company’s total revenue, respectively, and the top ten customers represented approximately 88% of its total revenue. As of September 30, 2015, two customers accounted for approximately 44% and 21% of the Company’s total accounts receivable. As of December 31, 2014, two customers accounted for 45% and 10% of the Company’s total accounts receivable.
Use of Estimates	Use of Estimates The preparation of financial statements in accordance with 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; valuation of excess and obsolete inventories; warranty reserves; litigation accrual and recognition of stock-based compensation, among others. Actual results could differ from these estimates. Summary of Significant Accounting Policies There have been no significant changes in the Company’s significant accounting policies in the three and nine months ended September 30, 2015, as compared to the significant accounting policies described in its Annual Report on Form 10-K for the year ended December 31, 2014.
Recent Accounting Pronouncements	Recent accounting pronouncements In September 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update ("ASU") 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments (“ASU 2015-16”). ASU 2015-16 requires an acquirer of a business to recognize adjustments to provisional amounts that are identified during the measurement period in the reporting period in which the adjustment amounts are determined. This guidance also requires acquirers to present separately on the face of the income statement, or disclose in the notes, the portion of the amount recorded in current-period earnings by line item that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. ASU 2015-16 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. The Company does not expect the adoption of this standard to have an impact on its consolidated financial statements. In July 2015, the FASB issued ASU 2015-12, Plan Accounting: Defined Benefit Pension Plans (Topic 960), Defined Contribution Pension Plans (Topic 962), Health and Welfare Benefit Plans (Topic 965): (Part I) Fully-Benefit R e sponsive Investment Contracts, (Part II) Plan Investment Disclosures, (Part III) Measurement D a te Practical Expedient (consensus of the FASB Emerging Issues Task Force (“ASU 2015-12”). ASU 2015-12 requires (1) a pension plan to use contract value as the only measure for fully benefit-responsive investment contracts, (2) simplifies and increases the effectiveness of the investment disclosure requirements for employee benefit plans, and (3) provides benefit plans with a measurement-date practical expedient similar to the practical expedient provided to employers. This ASU is effective for fiscal years beginning after December 15, 2015. E a rly adoption is permitted. The amendments in parts I and II should be applied retrospectively to all financial statements presented, while the amendments in part III should be applied prospectively. 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. E a rly adoption is permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs (“ASU 2015-03”). ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for the Company’s annual and interim reporting periods beginning after December 15, 2015, with early adoption permitted. In August 2015, the FASB issued ASU 2015-15, I n terest-Imputation of Interest (Subtopic 835-30): Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements-Amendments to SEC Paragraphs Pursuant to Staff Announcement at June 18, 2015 EIFT Meeting (“ASU 2015-15”). ASU 2015-15 clarifies the SEC would not object an entity deferring and presenting debt issuance costs associated with line-of-credit arrangements as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line-of-credit arrangement. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In April 2015, the FASB issued ASU 2015-05, Intangibles-Goodwill and Other-Internal Use Software (Subtopic 350-40): Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement (“ASU 2015-05”) to provide guidance to a customer’s accounting for cloud computing costs. Under ASC 2015-05, a customer must determine whether a cloud computing arrangement contains a software license and account for an arrangement that contains a software license element consistent with the accounting for other software licenses. An arrangement would contain a software license element if (a) the customer has the contractual right to take possession of the software at any time during the hosting period without significant penalty and (b) it is feasible for the customer to either run the software on its own hardware or contract with another party unrelated to the vendor to host the software. This guidance is effective for annual and interim periods beginning after December 15, 2015, with early adoption permitted. The Company is in the process of evaluating the impact of adoption on its consolidated financial statements. In January 2015, the FASB issued ASU 2015-01, Income Statement – Extraordinary and Unusual Items: Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items (“ASU 2015-01”) , which eliminates from U.S. GAAP the concept of extraordinary items. The guidance eliminates the separate presentation of extraordinary items on the income statement, net of tax and the related earnings per share, but does not affect the requirement to disclose material items that are unusual in nature or occurring infrequently. The new standard may be applied prospectively or retrospectively and is effective for annual reporting periods beginning after December 15, 2015 and interim periods within those annual periods, with early adoption permitted. The Company does not expect the adoption of this standard to have an impact 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. In April 2014, the FASB issued ASU No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity ("ASU 2014-08") which raises the threshold for a disposal to qualify as a discontinued operation and requires new disclosures of both discontinued operations and certain other disposals that do not meet the definition of a discontinued operation. ASU 2014-08 is effective for annual periods beginning on or after December 15, 2014. The Company’s adoption of this guidance on January 1, 2015 did not impact its consolidated financial statements.

Net income (loss) per share (Ta

Net income (loss) per share (Tables)	9 Months Ended
	Sep. 30, 2015
Earnings Per Share [Abstract]
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 for the periods indicated (in thousands, except per share amounts): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 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 loss per share, as their effect would have been antidilutive (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Employee stock options Restricted stock units Employee stock purchase plan — — Common stock warrants — —

Cash, cash equivalents, short24

Cash, cash equivalents, short-term investments, and restricted cash and investments (Tables)	9 Months Ended
	Sep. 30, 2015
Cash And Cash Equivalents [Abstract]
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 September 30, 2015 and December 31, 2014 (in thousands): September 30, 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 its cash equivalents, short-term investments, and restricted cash and investments in marketable securities designated as available-for-sale (in thousands): As of September 30, 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 — — — — — U.S. government securities — — — — — Commercial papers — — — — — — Variable rate demand notes — — — — — — Total $ $ $ $ $ $ $ — $ Reported within: Cash equivalents $ $ — $ — $ $ — $ — $ — $ — Short-term investments — — — — Restricted cash and investments, non-current — — — — — Total $ $ $ $ $ $ $ — $
Maturities of Marketable Securities	As of September 30, 2015 and December 31, 2014, maturities of marketable securities were as follows (in thousands): September 30, December 31, 2015 2014 Less than 1 year $ $ Due in 1 to 2 years — Due in 2 to 5 years — — Due after 5 years — Total $ $

Fair value disclosures (Tables)

Fair value disclosures (Tables)	9 Months Ended
	Sep. 30, 2015
Fair Value Disclosures [Abstract]
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 September 30, 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 $ $ — $ — $ $ $ — $ — $ Time deposits — — — — — — — — Money market accounts — — — — — — Corporate bonds — — — — Government-sponsored enterprise obligations — — — — — — U.S. government securities — — — — — — Commercial papers — — — — — — 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 September 30, 2015 As of December 31, 2014 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Penalty payment derivative (Note 10) $ — $ — $ $ $ — $ — $ $

Business combination (Tables)

Business combination (Tables)	9 Months Ended
	Sep. 30, 2015
Business combination [Abstract]
Summary of Purchase Accounting and Tangible and Intangible Assets Acquired	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 $
Purchase Price Allocation of Intangible Assets	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): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Revenue $ $ $ $ Net income (loss) $ $ $ $ Basic net income (loss) per share $ $ $ $ Diluted net income (loss) per share $ $ $ $

Balance sheet components (Table

Balance sheet components (Tables)	9 Months Ended
	Sep. 30, 2015
Balance Sheet Components [Abstract]
Restricted Cash and Investments	Restricted cash and investments consist of the following (See Note 8) (in thousands): September 30, 2015 December 31, 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 consists of the following (in thousands): September 30, 2015 December 31, 2014 Accounts receivable $ $ Trade notes receivable Allowance for doubtful accounts $ $
Inventories, net	Inventories, net consist of the following (in thousands): September 30, 2015 December 31, 2014 Raw materials $ $ Work in process Finished goods $ $ (1) Finished goods inventory at customer vendor managed inventory locations was $13.7 million and $6.4 million as of September 30, 2015 and December 31, 2014, respectively.
Purchased Intangible Assets	Purchased intangible assets consist of the following (in thousands): September 30, 2015 December 31, 2014 Gross Accumulated Net Gross Accumulated Net Assets Amortization Assets Assets Amortization Assets Technology and patents $ $ $ $ $ $ Customer relationships Leasehold interest Non-compete agreements — — $ $ $ $ $ $
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 condensed consolidated statements of operations (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 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 September 30, 2015, is as follows (in thousands): 2015 (remaining three months) $ 2016 2017 2018 2019 Thereafter $
Accrued Expenses and Other Current Liabilities	Accrued and other current liabilities consist of the following (in thousands): September 30, 2015 December 31, 2014 Employee-related $ $ 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): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Beginning balance $ $ $ $ Warranty accruals Settlements Ending balance $ $ $ $
Other Noncurrent Liabilities	Other noncurrent liabilities consist of the following (in thousands): September 30, 2015 December 31, 2014 Pension and other employee-related $ $ Other $ $

Restructuring (Tables)

Restructuring (Tables)	9 Months Ended
	Sep. 30, 2015
Restructuring And Related Activities [Abstract]
Restructuring and Related Costs	The following table summarizes activity associated with restructuring obligations during the nine months ended September 30, 2015 (in thousands): Workforce Reduction Facilities Total Restructuring obligations, December 31, 2014 $ $ $ Restructuring costs incurred — Cash payments Restructuring obligations, September 30, 2015 $ — $ $

Debt (Tables)

Debt (Tables)	9 Months Ended
	Sep. 30, 2015
Debt Disclosure [Abstract]
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 debt (in thousands, except percentages): September 30, 2015 December 31, 2014 Weighted Weighted Average Average Carrying Interest Carrying Interest Amount Rate Amount Rate Notes payable $ — $ — 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 September 30, 2015, maturities of long-term debt were as follows (in thousands): 2015 (remaining three months) $ 2016 2017 2018 2019 Thereafter $

Japan pension plans (Tables)

Japan pension plans (Tables)	9 Months Ended
	Sep. 30, 2015
Compensation And Retirement Disclosure [Abstract]
Periodic Pension Cost	Net periodic pension cost associated with these plans included the following components (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Service cost $ — $ — $ — $ Interest cost — — — Amortization — — — Net periodic pension costs $ — $ — $ — $

Stockholders' equity (Tables)

Stockholders' equity (Tables)	9 Months Ended
	Sep. 30, 2015
Stockholders Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income, Net of Related Taxes	The components of accumulated other comprehensive income, net of related taxes, were as follows (in thousands): September 30, 2015 December 31, 2014 Foreign currency translation adjustments $ $ Unrealized gains on available-for-sale securities Defined benefit pension plan adjustment $ $

Stock-based compensation (Table

Stock-based compensation (Tables)	9 Months Ended
	Sep. 30, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Based Compensation Expense	The following table summarizes the stock-based compensation expense recognized in the three and nine months ended September 30, 2015 and 2014 (in thousands): Three Months Ended Nine Months Ended September 30, September 30, 2015 2014 2015 2014 Cost of goods sold $ $ $ $ Research and development Sales and marketing General and administrative $ $ $ $
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: Three Months Ended September 30, Nine Months Ended September 30, Stock options 2015 2014 2015 2014 Weighted-average expected term (years) 5.6 5.8 5.4 5.5 Weighted-average volatility 63% 66% 64% 68% Risk-free interest rate 1.63% - 1.85% 1.62% - 1.88% 1.37% – 1.85% 1.62% – 1.88% Expected dividends — — — — Stock appreciation units Weighted-average expected term (years) 3.5 2.5 3.6 2.5 Weighted-average volatility 60% 54% 62% 56% Risk-free interest rate 0.28% – 1.38% 0.47% – 0.88% 0.25% – 1.57% 0.13% – 0.90% Expected dividends — — — — ESPP Weighted-average expected term (years) — — 0.7 0.7 Weighted-average volatility — — 58% 54% Risk-free interest rate — — 0.03% - 0.14% 0.05% – 0.13% Expected dividends — — — —
Summary of Stock Option and Restricted Stock Unit Activity	The following table summarizes the Company’s stock option and RSU activity during the nine months ended September 30, 2015 : Stock Options Restricted Stock Units Weighted Weighted Average Average Number of Exercise Number of Grant Date Shares Price Units Fair Value Balance at December 31, 2014 $ $ Granted $ $ Exercised/Converted $ $ Cancelled/Forfeited $ $ Balance at September 30, 2015 $ $

Income taxes (Tables)

Income taxes (Tables)	9 Months Ended
	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Income (Loss) before Income Taxes	Three Months Ended Nine Months Ended September 30, September 30, (in thousands) 2015 2014 2015 2014 Provision for income taxes $ $ $ $

Basis of Presentation and Sig34

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Huawei Technologies [Member] | Revenue [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk	41.00%	35.00%	40.00%	36.00%
Ciena Corporation [Member] | Revenue [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk	26.00%	17.00%	24.00%	15.00%
Alcatel-Lucent SA [Member] | Revenue [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk				11.00%
Company Top Ten Customers [Member] | Revenue [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk	92.00%	88.00%	91.00%	88.00%
Customer One [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk			44.00%		45.00%
Customer Two [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Percentage of concentration of credit risk			21.00%		10.00%

Net income (loss) per share (De

Net income (loss) per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Numerator:
Net income (loss)	$ 1,378	$ (1,937)	$ 3,269	$ (21,304)
Denominator:
Basic	40,367	32,383	36,303	31,930
Dilutive effect of equity awards	1,850		1,234
Diluted	42,217	32,383	37,537	31,930
Basic net income (loss) per share	$ 0.03	$ (0.06)	$ 0.09	$ (0.67)
Diluted net income (loss) per share	$ 0.03	$ (0.06)	$ 0.09	$ (0.67)

Net income (loss) per share (36

Net income (loss) per share (Details 2) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	1,282	4,665	1,696	4,665
Employee Stock Options [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	1,256	3,735	1,670	3,735
Restricted stock units [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share	26	668	26	668
Employee Stock Purchase Plan [Member]
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potentially dilutive securities, excluded from computation of diluted net income (loss) per share		258		258
Common Stock Warrants [Member]
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		4

Summary of Cash, Cash Equivalen

Summary of Cash, Cash Equivalents, Short-Term investments, and Restricted Cash and Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013
Cash and cash equivalents:
Cash	$ 30,298	$ 43,035
Cash equivalents	46,952
Cash and cash equivalents	77,250	43,035	$ 35,269	$ 57,101
Short-term investments	23,302
Restricted cash and investments:
Restricted cash and investments, current	3,062	5,504
Restricted cash and investments, non-current		15,750
Total restricted cash and investments	$ 3,062	$ 21,254

Summary of Cash, Cash Equival38

Summary of Cash, Cash Equivalents, Short-Term investments, and Restricted Cash and Investments (Details 2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 70,253	$ 8,291
Gross Unrealized Gains	3	6
Gross Unrealized Losses	(2)
Fair Value	70,254	8,297
Money Market Accounts [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	46,952
Fair Value	46,952
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	13,442	4,587
Fair Value	13,442	4,587
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	5,840	2,004
Gross Unrealized Gains	1	6
Gross Unrealized Losses	(2)
Fair Value	5,839	2,010
Foreign bonds and note
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	2,018
Gross Unrealized Gains	1
Fair Value	2,019
U.S. government securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	1,002
Gross Unrealized Gains	1
Fair Value	1,003
Commercial Papers
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	999
Fair Value	999
Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	46,952
Fair Value	46,952
Short Term Investments and Restricted Investments [Member] | Variable Rate Demand Notes [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		1,700
Fair Value		1,700
Short-Term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	23,301
Gross Unrealized Gains	3
Gross Unrealized Losses	(2)
Fair Value	$ 23,302
Restricted cash and investments, non-current [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		8,291
Gross Unrealized Gains		6
Fair Value		$ 8,297

Summary of Cash, Cash Equival39

Summary of Cash, Cash Equivalents, Short-Term investments, and Restricted Cash and Investments (Details 3) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015USD ($)item	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)item	Sep. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Fair Value Disclosures [Abstract]
Less than 1 year	$ 66,916		$ 66,916		$ 6,597
Due in 1 to 2 years	3,338		3,338
Due after 5 years					1,700
Total	70,254		70,254		$ 8,297
Impairment losses on its marketable securities	$ 0	$ 0	$ 0	$ 0
Investments in marketable securities in unrealized loss postion in excess of 12 months | item	0		0

Fair value disclosures (Details

Fair value disclosures (Details) - Fair Value, Measurements, Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	$ 70,254	$ 8,297
Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	14,445	4,587
Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	55,809	3,710
Money Market Funds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	13,442	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	13,442	4,587
Money Market Accounts [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	46,952
Money Market Accounts [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	46,952
Corporate Bonds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	5,839	2,010
Corporate Bonds [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	5,839	2,010
US Government-sponsored Enterprises Debt Securities [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	2,019
US Government-sponsored Enterprises Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	2,019
U.S. government securities
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	1,003
U.S. government securities | Fair Value, Inputs, Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	1,003
Commercial Papers
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	999
Commercial Papers | Fair Value, Inputs, Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets, fair value	999
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	411	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	$ 411	$ 424

Fair value disclosures (Detai41

Fair value disclosures (Details 2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Penalty payment derivative	$ 400	$ 500
Fair Value, Measurements, Recurring [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Penalty payment derivative	389	530
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Penalty payment derivative	$ 389	$ 530

Fair value disclosures (Detai42

Fair value disclosures (Details 3) - Fair Value, Measurements, Nonrecurring [Member] - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Assets Fair Value Disclosure	$ 0	$ 0
Liabilities measured at fair value	$ 0	$ 0

Business Combination (Details)

Business Combination (Details) - USD ($) $ in Thousands	Apr. 16, 2015	Jan. 02, 2015	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition [Line Items]
Acquisition-related costs			$ 180		$ 467
Revenue			83,560	$ 81,576	250,316	$ 227,195
Tunable Laser Product Lines From EMCORE Corporation [Member]
Business Acquisition [Line Items]
Total consideration	$ 17,000	$ 17,500
Cash consideration paid		1,500
Issuance of notes to the seller of acquired business	$ 15,500	$ 16,000
Acquisition-related costs					900
Tunable Laser Product Lines From EMCORE Corporation [Member] | Net Accounts Receivable [Member]
Business Acquisition [Line Items]
Reduction in Assumed Assets & Liabilities					200
Tunable Laser Product Lines From EMCORE Corporation [Member] | Net Inventories [Member]
Business Acquisition [Line Items]
Reduction in Assumed Assets & Liabilities					100
Tunable Laser Product Lines From EMCORE Corporation [Member] | Sales Tax Accrual [Member]
Business Acquisition [Line Items]
Reduction in Assumed Assets & Liabilities					100
EMCORE [Member] | Pro Forma [Member]
Business Acquisition [Line Items]
Acquisition-related costs					300	300
Revenue			$ 13,200		39,500
EMCORE [Member] | Intersegment Eliminations [Member] | Pro Forma [Member]
Business Acquisition [Line Items]
Revenue					$ 0	$ 0

Business Combination (Details 2

Business Combination (Details 2) - USD ($) $ in Thousands	Apr. 16, 2015	Jan. 02, 2015	Sep. 30, 2015
Intangible assets acquired:
Intangible assets acquired			$ 4,800
Less: fair value of liabilities assumed:
Goodwill			$ 1,115
Developed Technology [Member]
Fair value of assets acquired:
Useful Life (in years)			7 years
Intangible assets acquired:
Intangible assets acquired			$ 4,100
Customer relationships
Fair value of assets acquired:
Useful Life (in years)			2 years
Intangible assets acquired:
Intangible assets acquired			$ 700
Tunable Laser Product Lines From EMCORE Corporation [Member]
Total purchase consideration:
Cash paid		$ 1,500
Notes payable	$ 15,500	16,000
Total consideration	$ 17,000	$ 17,500
NeoPhotonics Semiconductor [Member]
Total purchase consideration:
Cash paid			1,500
Total consideration			16,982
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			23,354
Less: fair value of liabilities assumed:
Accounts payable			(7,427)
Accrued liabilities			(60)
Fair value of liabilities assumed total			(7,487)
Goodwill			1,115
NeoPhotonics Semiconductor [Member] | Notes Payable
Total purchase consideration:
Notes payable			15,482
NeoPhotonics Semiconductor [Member] | Developed Technology [Member]
Intangible assets acquired:
Intangible assets acquired			4,100
NeoPhotonics Semiconductor [Member] | Customer relationships
Intangible assets acquired:
Intangible assets acquired			$ 700

Business Combination (Details 3

Business Combination (Details 3) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Business combination [Abstract]
Allowance for doubtful accounts receivable current	$ 988	$ 241

Business Combination (Details 4

Business Combination (Details 4) - NeoPhotonics Semiconductor [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items]
Revenue	$ 83,560	$ 95,683	$ 250,316	$ 262,217
Net income (loss)	$ 1,404	$ (1,951)	$ 3,689	$ (24,781)
Basic net income (loss) per share	$ 0.03	$ (0.06)	$ 0.10	$ (0.78)
Diluted net income (loss) per share	$ 0.03	$ (0.06)	$ 0.10	$ (0.78)

Balance sheet components (Detai

Balance sheet components (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash and investments	$ 3,062	$ 21,254
Restricted cash and investments	3,062	5,504
Restricted cash and investments, non-current		15,750
Notes Payable
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash and investments	$ 3,062	3,754
Comerica Bank Term Loan [Member]
Restricted Cash And Cash Equivalents Items [Line Items]
Total restricted cash and investments		$ 17,500

Balance sheet components (Det48

Balance sheet components (Details 2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Receivables [Abstract]
Accounts receivable	$ 74,672	$ 69,839
Trade notes receivable	4,146	7,999
Allowance for doubtful accounts	(988)	(241)
Accounts receivable, Net ,Total	$ 77,830	$ 77,597

Balance sheet components (Det49

Balance sheet components (Details 3) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Raw materials	$ 29,487	$ 23,804
Work in process	13,866	13,600
Finished goods	27,394	19,943
Inventories	$ 70,747	$ 57,347

Balance sheet components (Det50

Balance sheet components (Details 4) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Inventory Disclosure [Abstract]
Finished goods, at vendor managed inventory locations	$ 13.7	$ 6.4

Balance sheet components (Det51

Balance sheet components (Details 5) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Finite Lived Intangible Assets [Line Items]
Gross Assets	$ 55,111	$ 50,996
Accumulated Amortization	(43,942)	(40,733)
Net Assets	11,169	10,263
Technology and patents
Finite Lived Intangible Assets [Line Items]
Gross Assets	37,685	34,023
Accumulated Amortization	(30,474)	(28,402)
Net Assets	7,211	5,621
Customer relationships
Finite Lived Intangible Assets [Line Items]
Gross Assets	15,226	14,725
Accumulated Amortization	(12,300)	(11,176)
Net Assets	2,926	3,549
Leasehold interest
Finite Lived Intangible Assets [Line Items]
Gross Assets	1,338	1,386
Accumulated Amortization	(306)	(293)
Net Assets	1,032	1,093
Non-compete agreements
Finite Lived Intangible Assets [Line Items]
Gross Assets	862	862
Accumulated Amortization	$ (862)	$ (862)

Balance sheet components (Det52

Balance sheet components (Details 6) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
Cost of goods sold	$ 836	$ 709	$ 2,512	$ 2,137
Operating expenses	447	378	1,344	1,136
Total	$ 1,283	$ 1,087	$ 3,856	$ 3,273

Balance sheet components (Det53

Balance sheet components (Details 7) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]
2015 (remaining three months)	$ 1,287
2,016	4,463
2,017	1,327
2,018	1,149
2,019	794
Thereafter	2,149
Net Assets	$ 11,169	$ 10,263

Balance sheet components (Det54

Balance sheet components (Details 8) - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2013
Accounts Payable And Accrued Liabilities Current [Abstract]
Employee-related	$ 13,519		$ 13,635
Accrued warranty	1,160	$ 1,254	1,751	$ 1,822	$ 1,811	$ 1,737
Penalty payment derivative	389		530
Deferred income tax liabilities	181		181
Other	6,157		6,631
Accrued and other current liabilities	$ 21,406		$ 22,728

Balance sheet components (Det55

Balance sheet components (Details 9) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Accounting Policies [Abstract]
Beginning balance	$ 1,254	$ 1,811	$ 1,751	$ 1,737
Warranty accruals	90	100	(85)	631
Settlements	(184)	(89)	(506)	(546)
Ending balance	$ 1,160	$ 1,822	$ 1,160	$ 1,822

Balance sheet components (Det56

Balance sheet components (Details 10) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Payables And Accruals [Abstract]
Pension and other employee-related	$ 5,362	$ 5,355
Other	2,185	1,871
Other noncurrent liabilities	$ 7,547	$ 7,226

Restructuring (Details)

Restructuring (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Restructuring Cost And Reserve [Line Items]
Restructuring costs incurred	$ 169
Cost of goods sold and Operating Expenses [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring costs incurred	$ 200

Restructuring (Details 2)

Restructuring (Details 2) $ in Thousands	9 Months Ended
	Sep. 30, 2015USD ($)
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	$ 154
Restructuring costs incurred	169
Cash payments	(313)
Restructuring obligations, ending balance	10
Workforce Reduction [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	54
Restructuring costs incurred	169
Cash payments	(223)
Facilities [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring obligations, beginning balance	100
Cash payments	(90)
Restructuring obligations, ending balance	$ 10

Components of Debt, Obligations

Components of Debt, Obligations, Weighted Average Interest Rate and Additional Fair Value Information Relating to Outstanding Debt Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Notes payable	$ 10,196	$ 12,771
Short-term borrowing		10,000
Total notes payable and short-term borrowing	10,196	22,771
Total long-term debt, current and non-current	35,838	23,336
Current portion of long-term debt	24,563	2,445
Long-term debt, net of current portion	11,005	20,891
Total long-term debt, net of unaccreted discount	35,568	23,336
Bank Borrowings [Member] | Comerica Bank [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	$ 23,800	$ 17,500
Long-term Debt Weighted Average Interest Rate	2.95%	3.16%
Bank Borrowings [Member] | Mitsubishi Bank [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount	$ 12,038
Long-term Debt Weighted Average Interest Rate	1.53%
Short Term Borrowing [Member]
Debt Instrument [Line Items]
Short-term Debt Weighted Average Interest Rate		3.18%
NeoPhotonics Semiconductor [Member]
Debt Instrument [Line Items]
Long-term debt, carrying amount		$ 5,836
Long-term Debt Weighted Average Interest Rate		1.50%
Long-Term Debt Current [Member]
Debt Instrument [Line Items]
Unaccreted discount within long-term debt, net of current portion	$ (72)
Long-Term Debt Non-Current [Member]
Debt Instrument [Line Items]
Unaccreted discount within long-term debt, net of current portion	$ (198)

Debt - Additional Information (

Debt - Additional Information (Details 2) $ in Thousands, ¥ in Millions

Apr. 21, 2015USD ($)

Apr. 16, 2015USD ($)

Feb. 25, 2015JPY (¥)

Feb. 25, 2015USD ($)

Jan. 02, 2015USD ($)

Mar. 29, 2013JPY (¥)

Mar. 31, 2015USD ($)

Feb. 28, 2015JPY (¥)

Feb. 28, 2015USD ($)

Jan. 31, 2015USD ($)

Nov. 30, 2014USD ($)

Oct. 31, 2014USD ($)

Jun. 30, 2015CNY (¥)

Sep. 30, 2015USD ($)

Sep. 30, 2014USD ($)

Dec. 31, 2014JPY (¥)

Sep. 30, 2015CNY (¥)

Sep. 30, 2015JPY (¥)

Sep. 30, 2015USD ($)

Jun. 30, 2015USD ($)

Feb. 25, 2015USD ($)

Dec. 31, 2014USD ($)

Sep. 30, 2014CNY (¥)

Sep. 30, 2014USD ($)

Debt Instrument [Line Items]

Repayment of notes payable

$ 20,072

$ 15,851

Restricted cash and investments

$ 3,062

$ 21,254

Comerica [Member] | Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

20,000

Short-term line of credit facility

23,800

0

Line Of Credit

23,800

Line of Credit Facility, Remaining Borrowing Capacity

30,000

Mitsubishi Bank [Member]

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 1,400,000,000

12,000

Bank Borrowings [Member]

Debt Instrument [Line Items]

Debt Instrument, Covenant Compliance

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.

Restricted cash and investments

$ 0

17,500

Bank Borrowings [Member] | Comerica [Member]

Debt Instrument [Line Items]

Short-term line of credit facility

17,500

Interest rate description

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%

Tunable Laser Product Lines From EMCORE Corporation [Member]

Debt Instrument [Line Items]

Issuance of notes to the seller of acquired business

$ 15,500

$ 16,000

Debt Instrument, Term

2 years

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

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

2.75%

Interest rate description

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 September 30, 2015 the rate on the LIBOR option was 2.95%.

Line of credit facility, interest rate

2.95%

2.95%

2.95%

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

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

3.00%

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

Debt Instrument [Line Items]

Note payable, interest rate

5.00%

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

Debt Instrument [Line Items]

Note payable, interest rate

13.00%

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

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.75%

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

Second Credit Facility Expires September 2015 [Member] | China

Debt Instrument [Line Items]

Credit facility, expiration date

Sep. 30, 2016

Sep. 30, 2016

Percentage of compensating balance requirement for bank acceptance drafts

30.00%

30.00%

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

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 5,000

Obligation bear interest

4.02%

Due date of the principal

Apr. 30, 2015

Line Of Credit

$ 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] | China | Libor Plus Rate [Member]

Debt Instrument [Line Items]

Obligation bear variable interest

3.71%

Second Short-Term Advance Financing Agreement Expires May 2015 [Member] | China

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 5,000

Obligation bear interest

2.33%

Due date of the principal

May 31, 2015

Service fees

1.00%

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

Debt Instrument [Line Items]

Due date of the principal and interest

Oct. 8, 2015

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

Debt Instrument [Line Items]

Debt instrument description of variable rate basis

LIBOR

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

Debt Instrument [Line Items]

Due date of the principal

Feb. 25, 2025

Feb. 25, 2025

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

Debt Instrument [Line Items]

Issuance of notes to the seller of acquired business

$ 15,500

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%

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

Line Of Credit

$ 15,800

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]

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]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

1.00%

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

¥ 500,000,000

$ 4,200

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%

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

Debt Instrument [Line Items]

Credit facility, expiration date

Jun. 30, 2016

Line of Credit Facility, Maximum Borrowing Capacity

¥ 120

$ 18,900

Loans Payable | Second Credit Facility Expires September 2015 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 133

20,900

¥ 133

$ 20,900

Notes Payable

Debt Instrument [Line Items]

Notes payable outstanding

¥ 700,000,000

5,800

Restricted cash and investments

3,062

$ 3,754

Notes Payable | NeoPhotonics Semiconductor [Member]

Debt Instrument [Line Items]

Obligation bear interest

1.50%

1.50%

Repayment 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]

Issuance of notes to the seller of acquired business | ¥

¥ 1,050,000,000

Bankers Acceptance

Debt Instrument [Line Items]

Restricted cash and investments, current

3,100

$ 3,800

Bankers Acceptance | China

Debt Instrument [Line Items]

Short-term line of credit facility

10,200

$ 12,800

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

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

¥ 171.4

$ 26,900

Bankers Acceptance | Second Credit Facility Expires September 2015 [Member] | China

Debt Instrument [Line Items]

Short-term line of credit facility

¥ 190

$ 29,900

¥ 190

$ 29,900

Maturities of Long -Term debt O

Maturities of Long -Term debt Outstanding (Details 3) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Maturities Of Long Term Debt [Abstract]
2015 (remaining three months)	$ 24,009
2,016	835
2,017	835
2,018	5,009
2,019	835
Thereafter	4,315
Long Term Debt	$ 35,838	$ 23,336

Japan pension plans (Details)

Japan pension plans (Details)	1 Months Ended	2 Months Ended	3 Months Ended	9 Months Ended
	May. 31, 2014USD ($)	Feb. 28, 2014USD ($)	Mar. 31, 2014USD ($)	Sep. 30, 2015USD ($)	Dec. 31, 2014USD ($)	Mar. 29, 2013item
Compensation And Retirement Disclosure [Abstract]
Number of Defined Benefit Pension Plans | item						2
Employer contributions	$ 2,000,000	$ 15,000
Conversion of plan, proceed from LAPIS				$ 300,000
Defined Benefit Plan, Curtailments			$ 100,000
Pension liability				5,100,000	$ 5,100,000
Pension liability included in accrued and other current liabilities				$ 100,000	$ 100,000

Japan pension plans (Details 2)

Japan pension plans (Details 2) $ in Thousands	9 Months Ended
	Sep. 30, 2014USD ($)
Compensation And Retirement Disclosure [Abstract]
Service cost	$ 53
Interest cost	13
Amortization	1
Net periodic pension costs	$ 67

Commitments and Contingencies (

Commitments and Contingencies (Details) € in Millions	May. 21, 2015	Apr. 02, 2015	Mar. 23, 2015EUR (€)	Mar. 23, 2015USD ($)	Sep. 16, 2013USD ($)	Apr. 27, 2012USD ($)	May. 05, 2010defendant	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Sep. 30, 2015USD ($)	Sep. 30, 2014USD ($)	Dec. 31, 2014USD ($)
Loss Contingencies [Line Items]
Number of defendants | defendant							4
Probable or reasonably possible loss								$ 0			$ 0
Operating leases, expiration date											2,023
Operating leases, future minimum payments due								6,200,000			$ 6,200,000
Operating leases, future minimum, sublease receipts								1,600,000			1,600,000
Rent expense								500,000		$ 500,000	1,700,000	$ 1,600,000
Penalty payment derivative								400,000			400,000		$ 500,000
Proceeds from public stock offering, net of offering costs						$ 39,800,000
Revenue								83,560,000		$ 81,576,000	250,316,000	$ 227,195,000
Securities lock up agreement period	180 days	60 days
Additional paid-in capital								507,969,000			507,969,000		$ 456,189,000
PendingLitigationMember
Loss Contingencies [Line Items]
Partial settlement of claims					$ 492,000
Accrual for estimated net litigation expense			€ 1	$ 1,100,000				0	$ 0
Embedded Derivative Financial Instruments [Member]
Loss Contingencies [Line Items]
Other non-current liability								5,000,000			5,000,000
RUSSIAN FEDERATION
Loss Contingencies [Line Items]
Exit fees											3,500,000
Exit fees for future											1,500,000
Indemnification Guarantee [Member]
Loss Contingencies [Line Items]
Probable or reasonably possible loss								0			0
Private Placement [Member] | Embedded Derivative Financial Instruments [Member]
Loss Contingencies [Line Items]
Penalty payment derivative								100,000			100,000
Additional paid-in capital								4,900,000			4,900,000
Private Placement [Member] | Performance Guarantee [Member]
Loss Contingencies [Line Items]
Other non-current liability								$ 30,000,000			$ 30,000,000

Stockholders' equity (Details)

Stockholders' equity (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2015	Sep. 30, 2015	Dec. 31, 2014	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
Common stock, par value		$ 0.0025	$ 0.0025
Sale of common stock shares	6,866,689
Sale of common stock upon the exercise of overallotment option	895,655
Public offering price	$ 7.25
Consideration raised on transaction	$ 45.6
Underwriting discounts	3
Other offering expenses	$ 1.2
Other Comprehensive Income Loss Reclassification Adjustment From AOCI For Sale Of Securities Before Ta		$ 0	$ 0
Accumulated deficit subject to restriction			$ 7.1
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
Common stock, par value				$ 0.0025
Minimum [Member]
Class Of Stock [Line Items]
Accumulated profits			10.00%
Employee Stock Options.
Class Of Stock [Line Items]
Common stock		7,009,303
Sale of common stock upon the exercise of overallotment option		102,711
Employee Stock Purchase Plan [Member]
Class Of Stock [Line Items]
Common stock		678,438

Stockholders' equity (Details 2

Stockholders' equity (Details 2) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Stockholders Equity Note [Abstract]
Foreign currency translation adjustment	$ 1,293	$ 5,391
Unrealized gains on available-for-sale securities	1	6
Defined benefit pension plan adjustment	(71)	(71)
Accumulated other comprehensive income, Net of tax	$ 1,223	$ 5,326

Stock-based compensation (Detai

Stock-based compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,436	$ 1,188	$ 5,418	$ 4,812
Cost of Goods Sold [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	339	203	1,119	988
Research and Development Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	363	339	1,357	1,454
Selling and Marketing Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	275	417	1,175	1,377
General and Administrative Expense [Member]
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 459	$ 229	$ 1,767	$ 993

Stock-based compensation (Det68

Stock-based compensation (Details 2)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Employee Stock Options.
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)	5 years 7 months 6 days	5 years 9 months 18 days	5 years 4 months 24 days	5 years 6 months
Weighted-average volatility	63.00%	66.00%	64.00%	68.00%
Risk-free interest rate Minimum	1.63%	1.62%	1.37%	1.62%
Risk-free interest rate Maximum	1.85%	1.88%	1.85%	1.88%
Expected dividends	0.00%	0.00%	0.00%	0.00%
Stock Appreciation Units (SARs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)	3 years 6 months	2 years 6 months	3 years 7 months 6 days	2 years 6 months
Weighted-average volatility	60.00%	54.00%	62.00%	56.00%
Risk-free interest rate Minimum	0.28%	0.47%	0.25%	0.13%
Risk-free interest rate Maximum	1.38%	0.88%	1.57%	0.90%
Expected dividends	0.00%	0.00%	0.00%	0.00%
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected term (years)			8 months 12 days	8 months 12 days
Weighted-average volatility			58.00%	54.00%
Risk-free interest rate Minimum			0.03%	0.05%
Risk-free interest rate Maximum			0.14%	0.13%
Expected dividends	0.00%	0.00%	0.00%	0.00%

Stock-based compensation (Det69

Stock-based compensation (Details 3) - $ / shares	3 Months Ended	9 Months Ended
	Jun. 30, 2015	Sep. 30, 2015
Number of Shares
Exercised/Converted	(895,655)
Employee Stock Options.
Number of Shares
Beginning Balance		4,899,713
Granted		256,780
Exercised/Converted		(102,711)
Cancelled/Forfeited		(126,677)
Ending Balance		4,927,105
Weighted Average Exercise Price
Beginning Balance		$ 4.07
Granted		5.27
Exercised/Converted		4.32
Cancelled/Forfeited		4.67
Ending Balance		$ 4.11
Restricted stock units [Member]
Number of Units
Beginning Balance		655,729
Granted		204,434
Exercised/Converted		(547,828)
Cancelled/Forfeited		(23,602)
Ending Balance		288,733
Weighted Average Exercise Price
Beginning Balance		$ 6.19
Granted		6.66
Exercised/Converted		6.05
Cancelled/Forfeited		5.37
Ending Balance		$ 6.85

Stock-based compensation (Det70

Stock-based compensation (Details 4) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Dec. 31, 2014
Stock Appreciation Units (SARs) [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance-based stock appreciation units	0	0
Shares outstanding	352,664	352,664	375,833
Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost, net of forecasted forfeitures	$ 41,000	$ 41,000

Income taxes (Details)

Income taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Tax Disclosure [Abstract]
Provision for income taxes	$ (1,157)	$ (902)	$ (2,698)	$ (1,761)

Income taxes (Details 2)

Income taxes (Details 2) - Foreign Country [Member] - Subsidiaries [Member]	9 Months Ended
	Sep. 30, 2015
Income Taxes [Line Items]
Effective income tax rate	15.00%
Income tax statutory rate	25.00%

Subsequent events

Subsequent events $ in Millions	Nov. 02, 2015USD ($)
Subsequent Event [Member] | EigenLight Corp Member
Subsequent Event [Line Items]
Unpaid purchase consideration	$ 0.4