SiTime (SITM) 10-K 2 Mar 20 2019 FY Annual report Financial data

Document And Entity Information

Document And Entity Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Feb. 28, 2020	Nov. 21, 2019
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Registrant Name	SiTime Corporation
Entity Central Index Key	0001451809
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 90,603,136
Entity Common Stock Shares Outstanding		15,060,542
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	SITM
Security Exchange Name	NASDAQ
Entity File Number	333-234305
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	02-0713868
Entity Address, Address Line One	5451 Patrick Henry Drive
Entity Address, City or Town	Santa Clara
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95054
City Area Code	408
Local Phone Number	328-4400
Document Annual Report	true
Document Transition Report	false
Documents Incorporated by Reference	Part III incorporates by reference certain information from the registrant’s definitive proxy statement for the 2020 Annual Meeting of Stockholders to be filed no later than 120 days after the conclusion of the registrant’s fiscal year ended December 31, 2019

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 63,418	$ 7,889
Accounts receivable, net	17,659	19,180
Related party accounts receivable	1,073	1,436
Inventories	11,911	20,543
Prepaid expenses and other current assets	5,601	4,056
Total current assets	99,662	53,104
Property and equipment, net	9,288	11,281
Intangible assets, net	4,489	8,142
Right-of-use assets, net	9,790
Other assets	162	162
Total assets	123,391	72,689
Current liabilities:
Accounts payable	3,869	5,025
Accrued expenses and other current liabilities	8,442	7,655
Related party loan obligations		3,000
Loan obligations	41,000	43,000
Total current liabilities	53,311	58,680
Deferred rent		2,436
Lease liabilities	7,940
Other long-term liabilities		558
Total liabilities	61,251	61,674
Commitments and contingencies (Note 6)
Stockholders’ equity:
Common stock, $0.0001 par value - 200,000 shares authorized; 14,968 and 10,000 shares issued and outstanding at December 31, 2019 and December 31, 2018	2	1
Additional paid-in capital	116,162	58,431
Accumulated deficit	(54,024)	(47,417)
Total stockholders’ equity	62,140	11,015
Total liabilities and stockholders’ equity	$ 123,391	$ 72,689

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares, issued	14,968,000	10,000,000
Common stock, shares, outstanding	14,968,000	10,000,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Revenue	$ 84,074	$ 85,214
Cost of revenue	44,516	49,009
Gross profit	39,558	36,205
Operating expenses:
Research and development	23,795	22,775
Selling, general and administrative	20,636	21,220
Total operating expenses	44,431	43,995
Loss from operations	(4,873)	(7,790)
Interest expense	(1,714)	(1,512)
Other expense, net	(28)	(66)
Loss before income taxes	(6,615)	(9,368)
Income tax benefit	8	26
Net loss	(6,607)	(9,342)
Net loss attributable to common stockholder and comprehensive loss	$ (6,607)	$ (9,342)
Net loss per share attributable to common stockholder, basic and diluted	$ (0.63)	$ (0.93)
Weighted-average shares used to compute basic and diluted net loss per share	10,558	10,000

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit
Beginning Balance at Dec. 31, 2017	$ 17,676	$ 1	$ 55,750	$ (38,075)
Beginning Balance, Shares at Dec. 31, 2017		10,000
Investment from MegaChips	1,850		1,850
Stock-based compensation expense	831		831
Net income (loss)	(9,342)			(9,342)
Ending Balance at Dec. 31, 2018	$ 11,015	$ 1	58,431	(47,417)
Ending Balance, Shares at Dec. 31, 2018	10,000,000	10,000
Stock-based compensation expense	$ 1,379		1,379
Net income (loss)	(6,607)			(6,607)
Issuance of common stock upon initial public offering net of underwriting discounts and commissions and other offering costs	56,353	$ 1	56,352
Issuance of common stock upon initial public offering net of underwriting discounts and commissions and other offerings costs, Shares		4,945
Common stock issued in connection with vesting of restricted stock units, Shares		23
Ending Balance at Dec. 31, 2019	$ 62,140	$ 2	$ 116,162	$ (54,024)
Ending Balance, Shares at Dec. 31, 2019	14,968,000	14,968

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (6,607)	$ (9,342)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities
Depreciation and amortization expense	8,273	7,413
Non-cash operating lease cost and other	1,380
Stock-based compensation expense	1,379	831
Inventory write-down	321	9,165
Changes in assets and liabilities:
Accounts receivable, net	1,521	1,688
Related party accounts receivable	363	326
Inventories	8,144	(13,982)
Prepaid expenses and other current assets	(3,145)	2,572
Accounts payable	(1,148)	(648)
Accrued expenses and other liabilities	(919)	1,122
Lease liabilities	(2,184)
Other assets and liabilities		(191)
Net cash provided by (used in) operating activities	7,378	(1,046)
Cash flows from investing activities
Purchase of property and equipment	(1,426)	(2,314)
Cash paid for intangibles	(1,776)	(2,698)
Net cash used in investing activities	(3,202)	(5,012)
Cash flows from financing activities
Proceeds from initial public offering, net of underwriting discounts and commissions and other offering costs	56,353
Proceeds from loans from financial institutions		21,000
Proceeds from investment from MegaChips		1,850
Principal payments on loan to MegaChips	(3,000)
Principal payments on loan to financial institutions	(2,000)	(18,000)
Net cash provided by financing activities	51,353	4,850
Net increase (decrease) in cash and cash equivalents	55,529	(1,208)
Cash and cash equivalents
Beginning of period	7,889	9,097
End of period	63,418	7,889
Supplemental disclosure of cash flow information
Interest paid during the period	2,167	1,310
Income taxes paid	1	1
Supplemental disclosure of noncash flow information
Unpaid property and equipment	77	61
Unpaid intangibles	$ 558	$ 1,116

The Company and Summary of Sign

The Company and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
The Company and Summary of Significant Accounting Policies	1. The Company and Summary of Significant Accounting Policies SiTime Corporation (the “Company”), was incorporated in the State of Delaware in December 2003. The Company is a provider of silicon timing systems. The Company primarily supplies oscillator products that are comprised of a MEMS resonator and clock IC that is integrated into a package, as well as standalone resonators. The Company has also started to sample clock ICs. The Company’s products are designed to address a wide range of applications across a broad array of end markets. The Company operates a fabless business model and leverages its global network of distributors and resellers to address the broad set of end markets that it serves. The Company was a wholly-owned subsidiary of MegaChips Corporation (“MegaChips”), a fabless semiconductor company based in Japan and traded on the Tokyo Stock Exchange until it completed its initial public offering in November 2019. MegaChips is now the largest shareholder of the Company and held approximately 66.8% of the Company’s outstanding common stock as of December 31, 2019. Reporting Calendar The Company’s fiscal year begins on January 1 of the year stated and ends on December 31 of the same year. The Company reports its results on a calendar year basis. Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation. Initial Public Offering On November 25, 2019, the Company completed its initial public offering (“IPO”), in which it issued and sold 4,945,000 shares of its common stock including the full exercise of the underwriters’ over-allotment option to purchase an additional 645,000 shares at $13.00 per share, resulting in net proceeds of $56.4 million after deducting underwriting discounts and commissions of $7.9 million and deferred offering costs of $3.4 million. Deferred offering costs consist primarily of accounting, legal, and other fees related to the Company’s IPO. Prior to the IPO, all deferred offering costs were capitalized in other assets, non-current in the consolidated balance sheets. After the IPO, $3.4 million of deferred offering costs were reclassified into stockholders’ equity as a reduction of the IPO proceeds in the consolidated balance sheet. We had no deferred offering costs within other assets, non-current in the consolidated balance sheet as of December 31, 2019 and 2018. Stock Split On October 16, 2019, a pricing committee of the Company’s board of directors approved an amendment and restatement of the Company’s certificate of incorporation to (i) increase the total number of authorized shares of its common stock to 200,000,000 shares, (ii) change the par value of its common stock to $0.0001 per share, and (iii) effect a 30,000-for-1 stock split of its common stock, which was within the range previously approved by its sole stockholder. These changes became effective upon filing of the Company’s amended and restated certificate of incorporation on October 18, 2019. Subsequently, on November 6, 2019, the Company’s board of directors and sole stockholder approved an amendment and restatement of the Company’s certificate of incorporation to effect a 2-for-3 reverse stock split of its common stock, which became effective on November 6, 2019. The share and per share amounts in these consolidated financial statements and accompanying notes have been adjusted to reflect such stock split and reverse stock split. Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The more significant areas requiring the use of management estimates and assumptions include revenue recognition, estimate of reserve for excess and obsolete inventories, sales and warranty reserves, estimate of reserves for accounts receivable, internally developed software capitalization, and valuation allowances for deferred tax assets. Actual results may differ materially from such estimates. Management believes that the estimates, and judgments upon which they rely, are reasonable based upon information available to them at the time that these estimates and judgments are made. To the extent that there are material differences between these estimates and actual results, the Company’s consolidated financial statements will be affected. Foreign Currency Remeasurement The Company and its wholly owned subsidiaries use the U.S. dollar as the functional currency. Foreign currency assets and liabilities are remeasured into U.S. dollars at the end-of-period exchange rates except for non-monetary assets and liabilities, which are measured at historical exchange rates. Revenue and expenses are remeasured using an average exchange rate in effect for the period, except for items related to non-monetary assets and liabilities, which are measured at historical exchange rates. Gains or losses from foreign currency remeasurement and transactions are included in other expense, net. For the years ended December 31, 2019 and 2018, foreign currency remeasurement and transactions gains and losses were less than $0.1 million. Cash and Cash Equivalents Cash and cash equivalents consist of cash balances in the Company’s bank checking and savings accounts and liquid short-term investments with original or remaining maturities of three months or less at the date of purchase, readily convertible to known amounts of cash. Fair Value Measurements The carrying amounts of the Company’s financial instruments, which include cash equivalents, accounts receivable, accounts payable, accrued liabilities, short-term debt obligations, and other current liabilities, approximate their fair values due to their short maturities. The Company determines fair value measurements used in its consolidated financial statements based upon the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value hierarchy distinguishes between (i) market participant assumptions developed based on market data obtained from independent sources (observable inputs), and (ii) an entity’s own assumptions about market participant assumptions developed based on the best information available in the circumstances (unobservable inputs). The fair value hierarchy consists of three broad levels, which gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are described below: Level 1: Valuations based on quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. Level 2: Valuations based on quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. Level 3: Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. At December 31, 2019 and 2018, cash balances in bank checking and savings accounts of $ 28.4 There were no transfers between Level 1 and Level 2 categories during any of the periods presented. Accounts Receivable and Allowances for Doubtful Accounts Accounts receivable are stated at amounts estimated by management to be net realizable value. An allowance for doubtful accounts is recorded when it is probable that amounts will not be collected based on historical collection trends, age of outstanding receivables, specific customer circumstances, and existing economic conditions. Accounts receivable are written-off when it becomes apparent that such amounts will not be collected. As of December 31, 2019 and 2018, the allowances for doubtful accounts were $ 0.1 Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash and cash equivalents and accounts receivable. The Company’s cash and cash equivalents amount is subject to concentration of credit risk. The Company maintains some cash and cash equivalents balances that are in excess of Federal Deposit Insurance Corporation insurance limits with financial institutions. The Company extends credit based on an evaluation of the customer’s financial condition and collateral is not typically required. The Company primarily sells its products through third-party distributors and resellers. For the years ended December 31, 2019 and 2018, three distributors directly accounted for 10% or more of the Company’s revenue. The following table discloses these customers’ percentage of revenue for the respective periods: Year Ended December 31, 2019 2018 Customer Quantek Technology Corporation 22 % 20 % Arrow Electronics, Inc. 19 18 Pernas Electronics Co. Ltd. 17 27 At December 31, 2019 and 2018, three customers accounted for 10% or more of accounts receivable, as disclosed below: As of December 31, 2019 2018 Customer Quantek Technology Corporation 32 % 34 % Arrow Electronics, Inc. 26 23 Pernas Electronics Co. Ltd. 12 23 Inventory Inventory is stated at the lower of standard cost (which approximates actual cost on a first-in, first-out basis) or net realizable value. The Company, at least quarterly, assesses the recoverability of all inventories to determine whether adjustments are required to record inventory at the lower of cost or net realizable value. The Company reduces the value of inventory by establishing excess and obsolete inventories reserves based on management’s assessment of future demand and market conditions, and may require estimates that may include uncertain elements. Actual demand may differ from forecasted demand and such differences may have a material effect on recorded value of inventory. Inventory write-downs, once established, are not released until the related inventory has been sold or scrapped. Rebates from the Company’s foundries are recorded as a reduction of inventory cost and are recognized in cost of revenue over the inventory turnover days of the Company. Most of the Company’s inventory is warehoused at its contract manufacturers. Property and Equipment Property and equipment are recorded at cost, less accumulated depreciation. Depreciation of property and equipment is recognized on a straight-line basis over the estimated useful lives of the respective assets as follows: Lab equipment 3 to 5 years Computer equipment 3 years Furniture and fixtures 5 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets The Company capitalizes the costs of purchased mask sets that are utilized during the photolithography phase of manufacturing our products, when technological feasibility and marketability have been established. The capitalization occurs upon the completion of a detailed design, the absence of significant development uncertainties and the determination of market acceptance. Such amounts are included in property and equipment in the consolidated balance sheets and are amortized to cost of revenue over their estimated useful lives. However, if significant uncertainties exist regarding the future utility of a particular mask set, then its related costs are expensed to research and development at the time the significant uncertainties are identified. Maintenance and repair costs are charged to expense as incurred, and expenditures that extend the useful lives of assets are capitalized. Upon retirement or sale of the property and equipment, the cost and related accumulated depreciation are removed from the balance sheet and the resulting gain or loss is recorded in other expense, net. Intangible Assets Intangible assets include the costs related to acquired software as well as costs related to software internally developed, or modified solely to meet the Company’s internal requirements, with no substantive plans to market such software at the time of development. The Company develops proprietary design automation software for its MEMS-based resonators. Costs incurred during the preliminary planning and evaluation stage of the project and during post implementation operational stage are expensed as incurred. Costs incurred during the application development stage of the software are capitalized. The Company defines the configuration and coding process as the application development stage. Capitalized internal use software costs are amortized, on a straight-line basis under cost of revenue over the estimated useful life of approximately 2 to 3 years. Purchased intangibles with finite lives are amortized using the straight-line method over the estimated economic lives of the assets of 3 years. Leases The Company applies the guidance in Accounting Standards Codification (“ASC”), Topic 842 to individual leases of assets. The Company recognizes a transaction as a lease when it receives substantially all of the economic benefits from and directs the use of specified property, plant and equipment. Operating leases are included in right-of-use (“ROU”), assets, accrued expenses and other current liabilities, and lease liabilities in the Company’s consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the present value of the Company’s obligation to make lease payments arising from the lease. The Company currently does not have any finance leases. The Company has elected the practical expedient within ASC Topic 842 to not separate lease and non-lease components within lease transactions for all classes of assets. Additionally, the Company has elected the short-term lease exception for all classes of assets and does not apply the recognition requirements for leases of 12 months or less, and recognizes lease payments for short-term leases as expense either straight-line over the lease term or as incurred depending on whether the lease payments are fixed or variable. These elections are applied consistently for all leases. When discount rates implicit in leases cannot be readily determined, the Company uses the applicable incremental borrowing rate at lease commencement to perform lease classification tests on lease components and to measure ROU assets and lease liabilities. The incremental borrowing rate used by the Company was based on the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term, an amount equal to the lease payments in a similar economic environment. Impairment of Long-Lived Assets The Company evaluates its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets. The Company determined that no events or changes in circumstances indicate that impairment of its long-lived assets has occurred. Warranty The Company provides limited lifetime warranty coverage on all of its products by guaranteeing that all timing components from the Company will be free from defects in workmanship and materials and will conform to specifications for the life of the system. This assurance-type warranty is not considered a separate performance obligation, and thus no transaction price is allocated to it. The Company records the warranty costs in cost of revenue in the consolidated statements of operations and comprehensive income (loss). The warranty reserve is calculated using historical claim information to project future warranty claims activity and is recorded within accrued expenses and other current liabilities and other long-term liabilities on the consolidated balance sheets based on the expected timing of the related payments. To date, the Company has had negligible returns of any defective products, and hence the warranty reserve balances as of December 31, 2019 and 2018 were less than $0.1 million. Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the carrying amounts in the consolidated financial statements of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards, using enacted tax rates in effect for the year in which the differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period that includes the enactment date. A valuation allowance is provided in order to reduce the deferred tax assets to a level which, more likely than not, will be realized. The Tax Cuts and Jobs Act of 2017 (the “Tax Act”), makes broad and complex changes to the U.S. tax code. These computations require significant judgments and estimates to be made regarding the interpretation of the provisions within the Tax Act along with the preparation and analysis of information not previously required. In conjunction with the Tax Act, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Act Income Taxes While the Company believes it has adequately reserved for its uncertain tax positions, no assurance can be given that the final tax outcome of these matters will not be different. The Company adjusts these reserves in light of changing facts and circumstances, such as the closing of a tax audit. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the provision for income taxes and the effective tax rate in the period in which such determination is made. The Company recognizes tax positions in the consolidated financial statements only when it is more likely than not that the position will be sustained upon examination by the relevant taxing authority. Liabilities are established for differences between positions taken in a tax return and amounts recognized in the consolidated financial statements. The Company reports interest and penalties related to uncertain tax positions, if any, in the provision for income taxes in the consolidated statements of operations and comprehensive income (loss). To the extent that accrued interest and penalties do not ultimately become payable, amounts accrued will be reduced and reflected as a reduction of the overall provision for income taxes in the period that such determination is made. Revenue Recognition The Company derives revenue from its product sales to distributors and resellers, who in turn sell to original equipment manufacturers or other end customers. The Company recognizes product revenue, at a point in time, upon shipment when it satisfies its performance obligations as evidenced by the transfer of control of its products to customers. The Company measures revenue based on the amount of consideration it expects to be entitled to in exchange for products. Variable consideration is estimated and reflected as an adjustment to the transaction price. The Company determines variable consideration, which consists primarily of price adjustments and product returns by estimating the amount of consideration the Company expects to receive from its customers based on historical experience of price adjustments and product returns. Initial estimates of price adjustments and product returns are updated at the end of each reporting period if additional information becomes available. Changes to the Company’s estimated variable consideration were not material for the periods presented. Since the Company’s performance obligations relate to contracts with a duration of less than one year, it does not disclose the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. The Company’s payment terms vary by contract type and type of customer and generally range from 30 to 60 days from shipment. The Company has also elected to recognize the cost for freight and shipping when control over the products sold passes to customers and revenue is recognized. As a practical expedient, the Company records the incremental costs of obtaining a contract, consisting primarily of sales commissions, when incurred because the amortization period is one year or less. These costs are recorded within sales and marketing expenses. The Company entered into a distribution agreement with MegaChips, whereby the Company appointed MegaChips as the exclusive distributor of its products in Japan. The Company recognizes revenue upon shipment derived from sales of products through MegaChips in the amount of expected payments from parties which purchased the products as adjusted for estimated price concessions and product returns. Cost of Revenue Cost of revenue consists of wafers acquired from third-party foundries, assembly, packaging, and test cost of the Company’s products paid to third-party contract manufacturers, and personnel and other costs associated with the manufacturing operations of the Company. Cost of revenue also includes depreciation of production equipment, inventory write-downs, amortization of internally developed software, shipping and handling costs, and allocation of overhead and facility costs. The Company also includes credits for rebates received from foundries to cost of revenue. Research and Development Expenses Research and development costs consist primarily of personnel cost, material cost, and facilities related expenses, incurred in the course of planned research and development of new products. Research and development costs are expensed as incurred. Selling, General and Administrative Expenses Selling, general and administrative expenses primarily consist of personnel costs, field application engineering support, travel costs, professional and consulting fees, accounting and audit fees, legal, advertising expenses, and allocated overhead costs. Selling, general and administrative costs are expensed as incurred. Advertising expenses were $0.3 million and $0.2 million, for the years ended December 31, 2019 and 2018. Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based awards made to employees, based on estimated fair values using the straight-line method over the requisite service period. The Company recognizes forfeitures as they occur. Fair value of grants before IPO On July 20, 2016, certain employees of the Company were granted restricted stock units (“RSUs”), of MegaChips. These units were valued at the fair market price of MegaChips’ common stock on the date of the grant, which was equal to the price of MegaChips’ common stock on the Tokyo Stock Exchange on the grant date. The associated grants were all vested and settled as of June 15, 2018 and no further grants were made by MegaChips. As part of the share based compensation agreement and due to the exercise restriction of 1 year at the time of vesting, the Company promised to advance cash to employees equal to the amount of payroll taxes that were due on vesting instead of issuing the employees restricted shares. The liability associated with the cash expense paid to the employee in lieu of restricted shares was treated as a liability-based award and was valued based on the estimate of the market price of the shares at each reporting date. Adjustments to the fair value of the liability are reported as compensation expense in the consolidated statements of operations and comprehensive income (loss). Fair value of grants after IPO The Company granted RSUs of its own common stock after the completion of its IPO and such grants were valued at the fair market value of the Company’s stock on the date of the grant. Net Income (Loss) Per Share Attributable to Common Stockholder Basic net income (loss) per share attributable to common stockholder is calculated by dividing the net income (loss) attributable to common stockholder by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net income (loss) per share is computed by dividing the net income (loss) attributable to common stockholder by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net income (loss) per share calculation, the Company does not have any stock issuances that are considered to be potentially dilutive securities. As such, the net income (loss) was attributed entirely to common stockholder. Because the Company has no potentially dilutive securities for the years ended December 31, 2019 and 2018, diluted net income (loss) per share attributable to common stockholder is the same as basic net income (loss) per share attributable to common stockholder for all periods presented. Comprehensive Income (Loss) The Company has no components of other comprehensive income (loss). Therefore, net income (loss) equals comprehensive income (loss) for all periods presented.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	12 Months Ended
	Dec. 31, 2019
Accounting Changes And Error Corrections [Abstract]
Recent Accounting Pronouncements	2. Recent Accounting Pronouncements Recently Adopted Accounting Guidance In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) New Accounting Pronouncements Not Yet Adopted In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Net Loss Per Share	3. Net Loss Per Share The following table summarizes the computation of basic and diluted net income (loss) per share attributable to common stockholder of the Company: Year Ended December 31 2019 2018 (in thousands, except per share data) Net loss attributable to common stockholder $ (6,607 ) $ (9,342 ) Weighted-average shares outstanding 10,558 10,000 Weighted average shares used to compute basic and diluted net loss per share 10,558 10,000 Net loss attributable to common stockholders per share, basic and diluted $ (0.63 ) $ (0.93 )

Balance Sheets Components

Balance Sheets Components	12 Months Ended
	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Balance Sheets Components	4. Balance Sheets Components Inventory Inventory consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Raw materials $ 304 $ 2,723 Work in progress 8,160 14,582 Finished goods 3,447 3,238 Total inventories $ 11,911 $ 20,543 The Company acquired approximately $8.0 million in inventory in anticipation of a product order from an end customer that did not materialize. As a result, the Company recorded an inventory write-down related to this inventory in first half of 2018 as there was no other active customer for the inventory at the time. The Company was subsequently able to sell approximately $3.0 million of such inventory in the fourth quarter of 2018 and $2.5 million in the year ended December 31, 2019 to the same customer. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Advance to suppliers $ 3,338 $ 539 Prepaid expenses 1,279 668 Other current assets 984 2,849 Total prepaid and other current assets $ 5,601 $ 4,056 Property and Equipment, Net Property and equipment, net consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Lab Equipment $ 17,376 $ 16,297 Computer Equipment 800 636 Furniture and fixtures 241 241 Construction in Progress 221 221 Leasehold improvements 4,074 4,013 22,712 21,408 Accumulated depreciation (13,424 ) (10,127 ) Total property and equipment, net $ 9,288 $ 11,281 Depreciation expense related to property and equipment was $3.3 million and $3.5 million for the years ended December 31, 2019 and 2018, respectively. Intangible Assets, Net Intangible assets, net consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Internal use software $ 10,022 $ 9,181 Purchased intangibles 4,793 4,355 14,815 13,536 Accumulated amortization (10,326 ) (5,394 ) Intangible assets, net $ 4,489 $ 8,142 Amortization expense for intangible assets was $4.9 million, and $3.9 million, As of December 31, 2019 and 2018, the Company had $2.0 million and $1.2 million, respectively, of intangibles that were still in development stage and were not being amortized. The estimated aggregate future amortization expense for intangible assets in development stage and subject to amortization as of December 31, 2019 is summarized as below: (in thousands) 2020 2,513 2021 920 2022 587 2023 469 2024 and beyond — 4,489 Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Accrued payroll and related benefits $ 1,880 $ 2,243 Accrued customer rebates 218 216 Accrued interest 72 520 Price adjustment and other revenue reserves 1,222 1,580 Short term lease liability 1,874 — Other accrued expenses 3,176 3,096 Total accrued expenses and other current liabilities $ 8,442 $ 7,655

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	5. Leases The Company leases real estate property under operating leases. The Company was also a lessee and a sublessor from an accounting perspective for its Santa Clara lease through March 31, 2019. The Company signed a non-cancellable operating lease agreement for its corporate headquarters in Santa Clara, California, that commenced on October 20, 2016 and will expire on December 31, 2026. The agreement provides for an option to renew for an additional 5 years and for monthly rent payments through the term of the lease. The Company also leases office space in Michigan, Malaysia, Japan, the Netherlands, and Ukraine all under non-cancellable operating leases with various expiration dates through May 2021. These leases are classified as operating leases. The remaining lease terms vary from few months to 7 years. For its leases the Company has options to extend the lease term for periods varying from one to five years. These renewal options are not considered in the remaining lease term unless it is reasonably certain that the Company will exercise such options. The Company also has variable lease payments that are primarily comprised of common area maintenance and utility charges. In the year ended December 31, 2018, the Company signed an agreement to lease equipment of $3.2 million for research and development and to help with the production of certain of its products, of which $1.6 million was prepaid before the leased equipment was put in service in 2019. The lease term for such equipment is approximately 10 years. As of December 31, 2019, only $0.8 million payments remain to be made for such equipment, which is recorded as short-term lease liability as of December 31, 2019 and paid by the Company in January 2020. The table below presents the lease-related assets and liabilities recorded on the consolidated balance sheet under the new accounting guidance of ASC Topic 842 as of December 31, 2019: (in thousands) Right-of-use assets $ 9,790 Lease liabilities included in accrued expenses and other current liabilities 1,874 Lease liabilities 7,940 Total operating lease liabilities $ 9,814 Weighted-average remaining lease term (years) 7.1 Weighted-average discount rate (1) 4.1 % (1) Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019. The table below presents certain information related to the lease costs for operating leases under the new accounting guidance of ASC Topic 842 for the year ended December 31, 2019: (in thousands) Operating lease cost $ 1,419 Short-term lease cost 313 Variable lease cost 494 Total lease cost $ 2,226 Rent expense for the year ended December 31, 2018 was $1.2 million under the previous accounting guidance of ASC Topic 840. Cash paid for operating lease liabilities was $3.9 million for the year ended December 31, 2019, which includes $1.6 million of prepaid lease payments. The Company sub-leased a portion of its Santa Clara facility through March 31, 2019 and received $0.3 million in sub-lease income for the year ended December 31, 2018 and $0.1 million for the year ended December 31, 2019, which was included in the short-term lease cost above. Undiscounted Cash Flows The table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the operating lease liabilities recorded on the consolidated balance sheet as of December 31, 2019: (in thousands) 2020 $ 2,108 2021 1,409 2022 1,441 2023 1,489 2024 1,532 2025 and beyond 3,212 Total minimum lease payments 11,191 Less: amount of lease payments representing interest (1,377 ) Present value of future minimum lease payments 9,814 Less: current obligations under leases (1,874 ) Long-term lease liabilities $ 7,940 As of December 31, 2019, the Company did not have any leases that had not yet commenced. As of December 31, 2018, the future minimum lease payments required under non-cancelable operating leases as defined under the previous accounting guidance of ASC Topic 840 were as follows: (in thousands) 2019 $ 1,514 2020 1,485 2021 1,451 2022 1,485 2023 1,533 2024 and beyond 4,877 Total minimum lease payments $ 12,345

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	6. Commitments and Contingencies Purchase Commitments The Company purchases components from a variety of suppliers and uses several contract manufacturers to provide manufacturing services for its products. During the normal course of business, in order to manage manufacturing lead times and to help ensure adequate component supply, the Company enters into agreements with the Company’s contract manufacturers and suppliers that allow them to procure inventory based upon criteria as defined by the Company. A portion of the Company’s reported purchase commitments arising from these agreements consists of firm, non-cancelable purchase commitments. In certain instances, these agreements allow the Company the option to cancel, reschedule, and adjust the Company’s requirements based on its business needs prior to when production starts. However, in situations where the Company is unable to cancel, reschedule, or adjust the purchase commitment due to changing customer demand, excess inventories could result in material inventory provisions. Commitments for MEMS Wafer Supplier Agreement The Company purchases MEMS wafers required for its silicon timing systems products under a multi-year manufacturing agreement with a third-party supplier. Under this agreement, the Company has agreed to minimum quantity purchase commitments and is responsible for research and development, tooling, and samples cost, in addition to wafer costs. The Company has historically met the supplier’s minimum wafer quantity requirements. The remaining tooling cost commitment under the agreement as of December 31, 2019 was $0.8 million and paid in 2020. Indemnification The Company is a party to a variety of agreements pursuant to which it may be obligated to indemnify other parties to such agreements with respect to certain matters. Typically, these obligations arise in the context of contracts that the Company has entered into, under which the Company customarily agrees to hold the other party harmless against losses arising from a breach of representations and covenants or terms and conditions related to such matters as the sale and/or delivery of its products, title to assets sold, certain intellectual property claims, defective products, specified environmental matters, and certain income taxes. Further, the Company’s obligations under these agreements may be limited in terms of time, amount, or the scope of its responsibility and in some instances, the Company may have recourse against third parties for certain payments made under these agreements. It is not possible to predict the maximum potential amount of future payments under these agreements due to the conditional nature of the Company’s obligations and the unique facts and circumstances involved in each particular agreement. Historically, the Company has had no indemnification claims under these agreements. Legal Matters From time to time, the Company may be a party to various litigation claims in the normal course of business. Legal fees and other costs associated with such actions are expensed as incurred. The Company assesses, in conjunction with legal counsel, the need to record a liability for litigation and contingencies. Accrual estimates are recorded when and if it is determined that such a liability for litigation and contingencies are both probable and reasonably estimable. As of the date of issuance of the financial statements, the Company was not subject to any litigation. No accruals for loss contingencies or recognition of actual losses have been recorded in any of the periods presented. In March 2019, VTT Technical Research Centre of Finland, Ltd. filed suit in the United States District Court for the Northern District of California alleging infringement by the Company of a patent relating to a specific combination of features set forth in the asserted patent. The complaint seeks unspecified monetary damages and injunctive relief. On January 22, 2020, the Company participated in a mediation that had been ordered by the Court. The case was not resolved at the mediation, and the proceedings will continue according to the current case management schedule. The Company has not accrued for a loss contingency relating to such matter as the loss is currently not probable and reasonably estimable.

Debt Obligations

Debt Obligations	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Debt Obligations	7. Debt Obligations The Company has borrowed against the short-term revolving lines of credit that it has arranged with financial institutions like The Bank of Tokyo-Mitsubishi UFJ, Ltd.(“MUFG”), and Sumitomo Mitsui Banking Corporation (“SMBC”), and MegaChips to fund its operations. The weighted-average interest rate on short-term borrowings outstanding as of December 31, 2019 and 2018 was 1.42% and 3.69%, respectively. Debt obligations as of December 31, 2019 and 2018 consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Revolving line of credit: MUFG $ 41,000 $ 41,000 SMBC — 2,000 MegaChips loan — 3,000 Balance 41,000 46,000 Less: Current portion of long-term debt (41,000 ) (46,000 ) Long-term debt $ — $ — As of December 31, 2019, debt obligations were as follows (dollars in thousands): Loan Start Date Loan Amount Annual Interest Rate Maturity Date Lender MUFG 12/19/2019 $ 38,000 2.97000 % 6/10/2020 MUFG 8/23/2019 3,000 3.10000 % 2/19/2020 $ 41,000 As of December 31, 2018, debt obligations were as follows (dollars in thousands): Lender Loan Start Date Loan Amount Annual Interest Rate Maturity Date MUFG 6/29/2018 $ 20,000 3.72000 % 6/28/2019 MUFG 8/23/2018 3,000 3.77000 % 8/23/2019 MUFG 9/24/2018 8,000 3.87000 % 9/24/2019 MUFG 12/19/2018 10,000 4.07000 % 12/19/2019 SMBC 12/19/2018 2,000 4.96500 % 12/19/2019 MegaChips 10/1/2018 3,000 3.20838 % 12/31/2018 $ 46,000 Revolving Line of Credit The Bank of Tokyo-Mitsubishi Credit Facility On August 31, 2015, the Company entered into a bank transaction agreement with MUFG. The agreement provided for a revolving line of credit with a maximum available borrowing of $20.0 million. The original maturity date of the revolving line of credit was June 30, 2017, which was renewed for an additional one year term. On June 29, 2018, the Company renewed its agreement with MUFG with a new maturity date of June 28, 2019 and also increased the revolving line of credit to $50.0 million. On December 19, 2018, the Company borrowed an additional $10.0 million loan under the credit line with MUFG which was extended through June 20, 2020. On June 27, 2019, the maturity of the $20.0 million loan was extended through December 31, 2019. On June 28, 2019, the Company renewed its agreement with MUFG with a new term through June 30, 2020. On August 23, 2019, the Company’s $3.0 million loan under the credit line with MUFG was extended through February 19, 2020. Such loan was repaid upon maturity in February 2020. On September 24, 2019, the Company’s $8.0 million loan under the credit line with MUFG was extended through December 19, 2019. On December 19, 2019, the Company combined and extended its $20.0 million loan, $10.0 million loan, and $8.0 million loan to June 10, 2020. Interest under the revolving line of credit is calculated at MUFG’s prevailing prime rate plus a margin of 2 percentage points which would be agreed by the Company at the time each loan was made. The interest rates on these loans vary depending on the date and term of each loan. Interest is due for payment on the maturity date of each loan. The Company did not incur any costs upon renewal of the revolving credit line or at the time of increase in the revolving line of credit. The agreement contains customary representations and warranties, affirmative covenants, and events of default upon the occurrence of certain events, such as nonpayment of amounts due under the revolving line of credit, violation of contractual provisions, or a material adverse change in the Company’s business. The agreement also includes customary administrative covenants, including a limitation on entering any transactions involving a merger or consolidation, reorganization, spin-off, liquidation, dissolution, winding up, or conveying, selling, leasing, licensing, or otherwise disposing of all or substantially all of the Company’s property, assets, or business. As of December 31, 2019 and 2018, the Company was in compliance with all covenants. The agreement provides that the Company will provide collateral if MUFG determines in consultation with the Company that additional collateral or guarantee would be necessary. The MUFG revolving line of credit is guaranteed by MegaChips. As of December 31, 2019 and 2018, the aggregate principal amount outstanding under the revolving credit line with MUFG was $41.0 million and remaining available credit line was $9.0 million as of December 31, 2019. Sumitomo Mitsui Banking Corporation Credit Facility On September 22, 2017, the Company entered into an uncommitted and revolving credit line agreement with SMBC. The revolving credit line has a maximum available borrowing availability of up to $20.0 million. The Company could draw loans under the revolving credit line from time to time through September 21, 2018, as long as the principal amount at any time did not exceed $20.0 million in the aggregate. Such term was extended for an additional year through September 20, 2019 and further extended for an additional year through September 21, 2020. Loans under the revolving credit line may have a maturity from one day to 12 months from the date of borrowing. The loans borrowed under the revolving line of credit bear a variable rate of interest based upon SMBC’s prevailing prime rate plus a margin of 1 percentage point which would be agreed by the Company at the time each loan is made. Interest is due for payment on the maturity date of each loan. SMBC has the right to terminate the revolving credit line in whole or part in its sole discretion. The Company did not incur any costs at the initiation of the revolving line of credit or upon renewal of the revolving credit line. The agreement contains customary representations and warranties, affirmative covenants, negative covenants, and events of default upon the occurrence of certain events, such as nonpayment of amounts due under the revolving line of credit, violation of contractual provisions, or a material adverse change in the Company’s business. In addition, the agreement includes a financial covenant for a minimum net worth, defined as total assets less total liabilities, of $0. The agreement also includes customary administrative covenants, including a limitation on entering any transactions involving a merger or consolidation, reorganization, spin-off, liquidation, dissolution, winding up, or conveying, selling, leasing, licensing, or otherwise disposing of all or substantially all of the Company’s property, assets, or business. As of December 31, 2019 and 2018, the Company was in compliance with all covenants. The agreement provides that the Company will provide collateral if SMBC determines in consultation with the Company that additional collateral or guarantee would be necessary. Use of proceeds from the loan is restricted for certain specified purposes. The SMBC revolving line of credit is also guaranteed by MegaChips. As of December 31, 2019 and 2018, the aggregate principal amount outstanding under the revolving credit line with SMBC was $0 and $2.0 million, respectively, and remaining available credit was $20.0 million as of December 31, 2019. The outstanding balance under the revolving line with SMBC was repaid on December 19, 2019 upon maturity. MegaChips Loan On September 13, 2016, the Company entered into a loan agreement with MegaChips for a revolving credit limit of up to $30.0 million (the “MegaChips Loan Agreement”). Loans under the MegaChips Loan Agreement bear interest at a rate equal to the interest rate at which MegaChips procured the funds from SMBC, plus 0.09%. Interest for each loan is due on the maturity date of each loan. Each loan drawn from MegaChips has a three-month term, which term was renewed on maturity. MegaChips has discretion whether to accept the Company’s request for a loan under the MegaChips Loan Agreement. The initial term of the MegaChips Loan Agreement is one year from the date of the agreement, which term is automatically renewed and extended every year unless either party provides written notice to the other party. The Company did not incur any costs at the time of initiation of such credit facility or at the time of extension of the term of the credit facility. The agreement contains usual and customary events of default upon the occurrence of certain events, such as nonpayment of amounts due under the revolving line of credit, violation of contractual provisions, a material adverse impact on the Company’s business, or its ability to perform under the agreement. The agreement includes customary administrative covenants but does not contain any negative covenants or conditions to borrowing. As of December 31, 2019 and 2018, the Company was in compliance with all covenants. As of December 31, 2019 and 2018, the aggregate principal amount outstanding under the credit facility with MegaChips was $0 million and $3.0 million, respectively, and remaining available credit was $30.0 million as of December 31, 2019. The outstanding balance under the revolving line with MegaChips was repaid on December 12, 2019 upon maturity.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Stockholders' Equity	8. Stockholders’ Equity The Company’s certificate of incorporation, as amended and currently in effect, authorizes the Company to issue 200,000,000 shares of common stock, par value $0.0001 per share. Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when and if declared by the board of directors, subject to the prior rights of holders of all classes of preferred stock outstanding. The Company has never declared any dividends.

Stock-based Compensation

Stock-based Compensation	12 Months Ended
	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-based Compensation	9. Stock-based Compensation SiTime Corporation 2019 Stock Incentive Plan Upon completion of its IPO in November 2019, the Company adopted the SiTime Corporation 2019 Stock Incentive Plan (the “2019 Plan”), which initially reserved approximately 3.4 million shares of the Company’s common stock. The 2019 Plan provides for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock unit awards, stock appreciation rights, performance stock awards, and other forms of equity compensation (collectively, “stock awards”), and cash awards, all of which may be granted to employees (including officers), directors, and consultants or affiliates. Awards granted under the 2019 Plan vest at the rate specified by the plan administrator, for restricted stock unit awards typically with quarterly vesting over four years. As of December 31, 2019, 0.3 million shares were still reserved for issuance MegaChips, the parent of the Company at the time, had also established a one-time Restricted Stock Unit Plan, which was adopted by MegaChips’ board of directors in May 2016. Under the Plan, certain employees of the Company were granted RSUs of MegaChips. MegaChips’ common stock is traded on the Tokyo Stock Exchange. The total number of shares authorized for grant under the Plan was 339,911. All units authorized to be granted under the Plan were granted to employees on July 20, 2016, the grant date. The units granted had a quarterly vesting schedule of two years. These units were valued at the fair market price of MegaChips’ common stock on the grant date, which was equivalent to approximately $11.89, based on the price of MegaChips’ common stock on the Tokyo Stock Exchange. The Company records a liability associated with the cash expense paid to the employee in lieu of restricted shares granted as part of the Plan and due to the exercise restriction of 1 year at the time of vesting. These cash advances were paid by MegaChips and accordingly, are shown as investment from MegaChips in the statement of stockholders’ equity. Adjustments to the fair value of the liability are reported as compensation expense in the consolidated statements of operations and comprehensive income (loss). The associated grants were all vested and settled as of June 15, 2018 and no further grants were made by MegaChips. Total stock-based compensation expense for employees recognized in the consolidated statements of operations and comprehensive income (loss) was as follows: Year Ended December 31, 2019 2018 (in thousands) Equity awards Cost of revenue $ 36 $ 19 Research and development 346 526 Selling, general and administrative 997 286 $ 1,379 $ 831 Liability based awards Cost of revenue $ — $ 39 Research and development — 1,062 Selling, general and administrative — 599 $ — $ 1,700 Total stock-based compensation expense $ 1,379 $ 2,531 The Company granted 3.0 million new time-based restricted stock awards in the year ended December 31, 2019 with quarterly vests primarily over two to five years. At December 31, 2019, there was $37.8 million unamortized compensation expense related to unvested stock awards. The unamortized compensation cost is expected to be recognized over a weighted average period of 4.40 years. Activity of RSUs granted under the Plan is set forth below: Grant Date Shares Fair Value Outstanding per share Balance at December 31, 2017 77,619 11.89 Granted — — Vested (76,296 ) 11.89 Forfeited (1,323 ) 11.89 Balance at December 31, 2018 — — Granted 3,012,399 13.00 Vested (23,077 ) 13.00 Forfeited — — Balance at December 31, 2019 2,989,322 13.00

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	10. Income Taxes The components of loss before income taxes were as follows: Years Ended December 31, 2019 2018 (in thousands) United States $ (6,485 ) $ (9,205 ) Foreign (130 ) (163 ) $ (6,615 ) $ (9,368 ) The components of income tax benefit were as follows: Years Ended December 31, 2019 2018 (in thousands) United States $ 8 $ 26 Foreign — — $ 8 $ 26 The material components of the deferred tax assets and liabilities consisted of net operating loss carry-forwards and tax credit carry-forwards. Years Ended December 31, 2019 2018 (in thousands) Deferred tax assets: Accrual, write-down and other $ 2,469 $ 2,931 Depreciation and amortization 76 (2,245 ) Net operating loss and credits carry forwards 42,949 44,810 Total gross deferred tax assets 45,494 45,496 Valuation allowance (45,494 ) (45,496 ) Total net deferred tax assets $ — $ — The net valuation allowance decreased by less than $0.1 million for the year ended December 31, 2019. A reconciliation of the Company’s effective tax rate to the statutory U.S. federal rate is as follows: Years Ended December 31, 2019 2018 (in thousands) US Federal Rate 21.0 % 21.0 % R&D Credits (10.9 ) 9.4 Permanent differences and others (18.3 ) 4.2 Change in valuation allowance 8.2 (34.3 ) 0.0 % 0.3 % The reported amount of income tax expense differs from an expected amount based on statutory rates primarily due to the Company’s valuation allowance. As of December 31, 2019 and 2018, based on the available objective evidence, management believes it is more likely than not that the net deferred tax assets will not be realized. Accordingly, management has applied a full valuation allowance against its net deferred tax assets at December 31, 2019 and 2018. At December 31, 2019 and 2018, the Company has federal net operating loss carry-forwards of approximately $156.5 million and $160.7 million, respectively, and state net operating loss carry-forwards of approximately $63.7 million and $63.9 million, respectively. At December 31, 2019 the Company has net operating loss carryforwards for foreign income tax purposes of approximately $1.3 million. The Company did not have any net operating loss carryforwards for foreign income tax purposes at December 31, 2018. These federal, state, and foreign net operating loss carry-forwards will expire beginning in 2025, 2028, and 2028, respectively. At December 31, 2019 and 2018, the Company also has federal research and development tax credit carry-forwards of approximately $3.9 million and $4.6 million, respectively, and state research and development tax credit carry-forwards of approximately $3.6 million and $4.1 million, respectively. The federal tax credits begin to expire in 2025, and the California tax credits carry forward indefinitely. Utilization of the net operating loss carry-forwards and credits may be subject to a substantial annual limitation due to the ownership change limitations provided by the Internal Revenue Code of 1986, as amended (“the Code”), and similar state provisions. The annual limitation may result in the expiration of net operating losses and credits before utilization. As of December 31, 2019 and 2018, the Company had $2.2 million and $2.2 million of total unrecognized tax benefits. The Company currently has a full valuation allowance against its net deferred tax assets which would impact the timing of the effective tax rate benefit should any of these uncertain tax positions be favorably settled in the future. If the Company is able to eventually recognize these uncertain tax positions, none of the unrecognized benefit would reduce the Company’s effective tax rate due to full valuation allowance of the Company’s deferred tax assets. The Company’s policy is to record interest and penalties related to unrecognized tax benefits as income tax expense. During the years ended December 31, 2019 and 2018, the Company had immaterial amounts related to the accrual of interest and penalties. A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows: December 31, 2019 2018 (in thousands) Beginning balance $ 2,198 $ 1,901 Decrease in balance related to tax position taken during prior periods (14 ) — Increase in balance related to tax position taken during the current period — 297 Ending balance $ 2,184 $ 2,198 The Company does not have any tax positions for which it is reasonably possible the total amount of gross unrecognized tax benefits will increase or decrease within 12 months of the years ended December 31, 2019 and 2018. The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal, state, local, and foreign jurisdictions, where applicable. Due to the Company’s net losses, its federal, state and local, and foreign tax returns since inception are subject to audit. As of December 31, 2019, the tax years that remain subject to examination by the major tax jurisdictions under the statute of limitations are as follows: Jurisdiction Earliest Tax Year Subject to Examination U.S. federal 2005 California State 2008

401 (k) Plan

401 (k) Plan	12 Months Ended
	Dec. 31, 2019
Defined Contribution Pension And Other Postretirement Plans Disclosure [Abstract]
401 (k) Plan	11. 401(k) Plan The Company has a 401(k) retirement plan that qualifies as a defined contribution plan. All employees are eligible to participate on the first day of the month following their hire date with the Company. Under the defined contribution plan, employees may contribute the lesser of 90% of their pre-tax salaries per year or the maximum contribution allowed under the Code. The Company may make discretionary matching contributions, if deferral contributions are made by the employees. The Company’s matching contributions for the years ended December 31, 2019 and 2018 resulted in expense of $0.6 million in each year.

Segment Information and Operati

Segment Information and Operations by Geographic Area	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Segment Information and Operations by Geographic Area	12. Segment Information and Operations by Geographic Area The Company operates in one reportable segment related to the design, development, and sale of silicon timing systems solutions. The chief operating decision maker, for the Company is the Chief Executive Officer. The Company’s Chief Executive Officer reviews operating results on an aggregate basis and manages the Company’s operations as a whole for the purpose of evaluating financial performance and allocating resources. Accordingly, the Company has determined that it has a single reportable and operating segment structure. The following table sets forth revenue by country, based on ship-to destinations, for countries with 10% or more of the Company’s revenue during any of the periods presented: Year Ended December 31, 2019 December 31, 2018 (in thousands) Taiwan $ 39,060 $ 45,107 Hong Kong 16,534 16,204 United States 5,677 6,061 Other 22,803 17,842 Total $ 84,074 $ 85,214 The Company’s long-lived assets in the U.S. attributable to operations as of December 31, 2019 and 2018 were 97% of total property and equipment and intangible assets.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Party Transactions	13. Related Party Transactions The Company entered into a distribution agreement with MegaChips, whereby the Company appointed MegaChips as the exclusive distributor of its products in Japan. The Company sells products through MegaChips to distributors, resellers, or direct customers in Japan. The Company pays MegaChips a fixed percentage of the revenue as sales commission, which is recorded as commission expense and included in sales and marketing in the consolidated statements of operations and comprehensive income (loss). See Note 7, “Debt Obligations” for more information regarding the Company’s loan agreement with MegaChips. The following is a summary of significant balances, transactions and payments with the related parties. December 31, 2019 December 31, 2018 (in thousands) MegaChips Accounts receivable $ 1,073 $ 1,436 Prepaid expenses and other current assets 18 — Accounts payable 220 194 Loan from MegaChips — 3,000 Year ended December 31, 2019 2018 (in thousands) MegaChips Sales through distribution agreement $ 5,071 $ 5,810 License expense 158 — Commission expense 202 368 Interest expense 94 95 Year Ended December 31, 2019 2018 (in thousands) MegaChips Cash paid for principal $ 3,000 $ — Cash paid for interest 94 95 Cash paid for commissions 202 368 Cash paid for licenses 329 —

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Events	14. Subsequent Events On February 19, 2020, the Company repaid its outstanding loan of $3.0 million with MUFG upon maturity. UNAUDITED QUARTERLY FINANCIAL DATA Fiscal Year 2019 Three Months Ended December 31, 2019 September 30, 2019 June 30, 2019 March 31, 2019 (in thousands except per share data) Revenue $ 28,089 $ 25,325 $ 15,843 $ 14,817 Gross profit 13,448 12,147 6,374 7,589 Total operating expenses 12,418 10,647 11,355 10,011 Income (loss) from operations 1,030 1,500 (4,981 ) (2,422 ) Net income (loss) 633 1,079 (5,449 ) (2,870 ) Net income (loss) per share basic and diluted 0.05 0.11 (0.54 ) (0.29 ) Fiscal Year 2018 December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 (in thousands except per share data) Revenue $ 22,851 $ 21,694 $ 14,911 $ 25,758 Gross profit 13,751 10,662 6,995 4,797 Total operating expenses 11,661 9,915 10,974 11,445 Income (loss) from operations 2,090 747 (3,979 ) (6,648 ) Net income (loss) 1,650 296 (4,319 ) (6,969 ) Net income (loss) per share basic and diluted 0.17 0.03 (0.43 ) (0.70 )

Schedule II - Valuation and Qua

Schedule II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2019
Valuation And Qualifying Accounts [Abstract]
SEC Schedule, 12-09, Schedule of Valuation and Qualifying Accounts Disclosure [Text Block]	SCHEDULE II Valuation and Qualifying Accounts Balance at Beginning of Period Additions Charged to Expenses or Other Accounts Deductions Credited to Expenses or Other Accounts Balance at End of Period (in thousands) Allowance for doubtful accounts receivable Year Ended December 31, 2019 $ 168 $ — $ (39 ) $ 129 Year Ended December 31, 2018 $ 125 $ 43 $ — $ 168 Deferred tax valuation allowance Year Ended December 31, 2019 $ 45,496 $ (2 ) $ — $ 45,494 Year Ended December 31, 2018 $ 42,308 $ 3,188 $ — $ 45,496

The Company and Summary of Si_2

The Company and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Reporting Calendar	Reporting Calendar The Company’s fiscal year begins on January 1 of the year stated and ends on December 31 of the same year. The Company reports its results on a calendar year basis.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany transactions and balances have been eliminated in consolidation.
Initial Public Offering	Initial Public Offering On November 25, 2019, the Company completed its initial public offering (“IPO”), in which it issued and sold 4,945,000 shares of its common stock including the full exercise of the underwriters’ over-allotment option to purchase an additional 645,000 shares at $13.00 per share, resulting in net proceeds of $56.4 million after deducting underwriting discounts and commissions of $7.9 million and deferred offering costs of $3.4 million. Deferred offering costs consist primarily of accounting, legal, and other fees related to the Company’s IPO. Prior to the IPO, all deferred offering costs were capitalized in other assets, non-current in the consolidated balance sheets. After the IPO, $3.4 million of deferred offering costs were reclassified into stockholders’ equity as a reduction of the IPO proceeds in the consolidated balance sheet. We had no deferred offering costs within other assets, non-current in the consolidated balance sheet as of December 31, 2019 and 2018.
Stock Split	Stock Split On October 16, 2019, a pricing committee of the Company’s board of directors approved an amendment and restatement of the Company’s certificate of incorporation to (i) increase the total number of authorized shares of its common stock to 200,000,000 shares, (ii) change the par value of its common stock to $0.0001 per share, and (iii) effect a 30,000-for-1 stock split of its common stock, which was within the range previously approved by its sole stockholder. These changes became effective upon filing of the Company’s amended and restated certificate of incorporation on October 18, 2019. Subsequently, on November 6, 2019, the Company’s board of directors and sole stockholder approved an amendment and restatement of the Company’s certificate of incorporation to effect a 2-for-3 reverse stock split of its common stock, which became effective on November 6, 2019. The share and per share amounts in these consolidated financial statements and accompanying notes have been adjusted to reflect such stock split and reverse stock split.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. The more significant areas requiring the use of management estimates and assumptions include revenue recognition, estimate of reserve for excess and obsolete inventories, sales and warranty reserves, estimate of reserves for accounts receivable, internally developed software capitalization, and valuation allowances for deferred tax assets. Actual results may differ materially from such estimates. Management believes that the estimates, and judgments upon which they rely, are reasonable based upon information available to them at the time that these estimates and judgments are made. To the extent that there are material differences between these estimates and actual results, the Company’s consolidated financial statements will be affected.
Foreign Currency Remeasurement	Foreign Currency Remeasurement The Company and its wholly owned subsidiaries use the U.S. dollar as the functional currency. Foreign currency assets and liabilities are remeasured into U.S. dollars at the end-of-period exchange rates except for non-monetary assets and liabilities, which are measured at historical exchange rates. Revenue and expenses are remeasured using an average exchange rate in effect for the period, except for items related to non-monetary assets and liabilities, which are measured at historical exchange rates. Gains or losses from foreign currency remeasurement and transactions are included in other expense, net. For the years ended December 31, 2019 and 2018, foreign currency remeasurement and transactions gains and losses were less than $0.1 million.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist of cash balances in the Company’s bank checking and savings accounts and liquid short-term investments with original or remaining maturities of three months or less at the date of purchase, readily convertible to known amounts of cash.
Fair Value Measurements	Fair Value Measurements The carrying amounts of the Company’s financial instruments, which include cash equivalents, accounts receivable, accounts payable, accrued liabilities, short-term debt obligations, and other current liabilities, approximate their fair values due to their short maturities. The Company determines fair value measurements used in its consolidated financial statements based upon the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The fair value hierarchy distinguishes between (i) market participant assumptions developed based on market data obtained from independent sources (observable inputs), and (ii) an entity’s own assumptions about market participant assumptions developed based on the best information available in the circumstances (unobservable inputs). The fair value hierarchy consists of three broad levels, which gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are described below: Level 1: Valuations based on quoted prices in active markets for identical assets or liabilities that the entity has the ability to access. Level 2: Valuations based on quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable data for substantially the full term of the assets or liabilities. Level 3: Valuations based on inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. At December 31, 2019 and 2018, cash balances in bank checking and savings accounts of $ 28.4 There were no transfers between Level 1 and Level 2 categories during any of the periods presented.
Accounts Receivable and Allowances for Doubtful Accounts	Accounts Receivable and Allowances for Doubtful Accounts Accounts receivable are stated at amounts estimated by management to be net realizable value. An allowance for doubtful accounts is recorded when it is probable that amounts will not be collected based on historical collection trends, age of outstanding receivables, specific customer circumstances, and existing economic conditions. Accounts receivable are written-off when it becomes apparent that such amounts will not be collected. As of December 31, 2019 and 2018, the allowances for doubtful accounts were $ 0.1
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash and cash equivalents and accounts receivable. The Company’s cash and cash equivalents amount is subject to concentration of credit risk. The Company maintains some cash and cash equivalents balances that are in excess of Federal Deposit Insurance Corporation insurance limits with financial institutions. The Company extends credit based on an evaluation of the customer’s financial condition and collateral is not typically required. The Company primarily sells its products through third-party distributors and resellers. For the years ended December 31, 2019 and 2018, three distributors directly accounted for 10% or more of the Company’s revenue. The following table discloses these customers’ percentage of revenue for the respective periods: Year Ended December 31, 2019 2018 Customer Quantek Technology Corporation 22 % 20 % Arrow Electronics, Inc. 19 18 Pernas Electronics Co. Ltd. 17 27 At December 31, 2019 and 2018, three customers accounted for 10% or more of accounts receivable, as disclosed below: As of December 31, 2019 2018 Customer Quantek Technology Corporation 32 % 34 % Arrow Electronics, Inc. 26 23 Pernas Electronics Co. Ltd. 12 23
Inventory	Inventory Inventory is stated at the lower of standard cost (which approximates actual cost on a first-in, first-out basis) or net realizable value. The Company, at least quarterly, assesses the recoverability of all inventories to determine whether adjustments are required to record inventory at the lower of cost or net realizable value. The Company reduces the value of inventory by establishing excess and obsolete inventories reserves based on management’s assessment of future demand and market conditions, and may require estimates that may include uncertain elements. Actual demand may differ from forecasted demand and such differences may have a material effect on recorded value of inventory. Inventory write-downs, once established, are not released until the related inventory has been sold or scrapped. Rebates from the Company’s foundries are recorded as a reduction of inventory cost and are recognized in cost of revenue over the inventory turnover days of the Company. Most of the Company’s inventory is warehoused at its contract manufacturers.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost, less accumulated depreciation. Depreciation of property and equipment is recognized on a straight-line basis over the estimated useful lives of the respective assets as follows: Lab equipment 3 to 5 years Computer equipment 3 years Furniture and fixtures 5 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets The Company capitalizes the costs of purchased mask sets that are utilized during the photolithography phase of manufacturing our products, when technological feasibility and marketability have been established. The capitalization occurs upon the completion of a detailed design, the absence of significant development uncertainties and the determination of market acceptance. Such amounts are included in property and equipment in the consolidated balance sheets and are amortized to cost of revenue over their estimated useful lives. However, if significant uncertainties exist regarding the future utility of a particular mask set, then its related costs are expensed to research and development at the time the significant uncertainties are identified. Maintenance and repair costs are charged to expense as incurred, and expenditures that extend the useful lives of assets are capitalized. Upon retirement or sale of the property and equipment, the cost and related accumulated depreciation are removed from the balance sheet and the resulting gain or loss is recorded in other expense, net.
Intangible Assets	Intangible Assets Intangible assets include the costs related to acquired software as well as costs related to software internally developed, or modified solely to meet the Company’s internal requirements, with no substantive plans to market such software at the time of development. The Company develops proprietary design automation software for its MEMS-based resonators. Costs incurred during the preliminary planning and evaluation stage of the project and during post implementation operational stage are expensed as incurred. Costs incurred during the application development stage of the software are capitalized. The Company defines the configuration and coding process as the application development stage. Capitalized internal use software costs are amortized, on a straight-line basis under cost of revenue over the estimated useful life of approximately 2 to 3 years. Purchased intangibles with finite lives are amortized using the straight-line method over the estimated economic lives of the assets of 3 years.
Leases	Leases The Company applies the guidance in Accounting Standards Codification (“ASC”), Topic 842 to individual leases of assets. The Company recognizes a transaction as a lease when it receives substantially all of the economic benefits from and directs the use of specified property, plant and equipment. Operating leases are included in right-of-use (“ROU”), assets, accrued expenses and other current liabilities, and lease liabilities in the Company’s consolidated balance sheets. ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the present value of the Company’s obligation to make lease payments arising from the lease. The Company currently does not have any finance leases. The Company has elected the practical expedient within ASC Topic 842 to not separate lease and non-lease components within lease transactions for all classes of assets. Additionally, the Company has elected the short-term lease exception for all classes of assets and does not apply the recognition requirements for leases of 12 months or less, and recognizes lease payments for short-term leases as expense either straight-line over the lease term or as incurred depending on whether the lease payments are fixed or variable. These elections are applied consistently for all leases. When discount rates implicit in leases cannot be readily determined, the Company uses the applicable incremental borrowing rate at lease commencement to perform lease classification tests on lease components and to measure ROU assets and lease liabilities. The incremental borrowing rate used by the Company was based on the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term, an amount equal to the lease payments in a similar economic environment.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company evaluates its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets. The Company determined that no events or changes in circumstances indicate that impairment of its long-lived assets has occurred.
Warranty	Warranty The Company provides limited lifetime warranty coverage on all of its products by guaranteeing that all timing components from the Company will be free from defects in workmanship and materials and will conform to specifications for the life of the system. This assurance-type warranty is not considered a separate performance obligation, and thus no transaction price is allocated to it. The Company records the warranty costs in cost of revenue in the consolidated statements of operations and comprehensive income (loss). The warranty reserve is calculated using historical claim information to project future warranty claims activity and is recorded within accrued expenses and other current liabilities and other long-term liabilities on the consolidated balance sheets based on the expected timing of the related payments. To date, the Company has had negligible returns of any defective products, and hence the warranty reserve balances as of December 31, 2019 and 2018 were less than $0.1 million.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the carrying amounts in the consolidated financial statements of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards, using enacted tax rates in effect for the year in which the differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in earnings in the period that includes the enactment date. A valuation allowance is provided in order to reduce the deferred tax assets to a level which, more likely than not, will be realized. The Tax Cuts and Jobs Act of 2017 (the “Tax Act”), makes broad and complex changes to the U.S. tax code. These computations require significant judgments and estimates to be made regarding the interpretation of the provisions within the Tax Act along with the preparation and analysis of information not previously required. In conjunction with the Tax Act, the SEC staff issued Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Act Income Taxes While the Company believes it has adequately reserved for its uncertain tax positions, no assurance can be given that the final tax outcome of these matters will not be different. The Company adjusts these reserves in light of changing facts and circumstances, such as the closing of a tax audit. To the extent that the final tax outcome of these matters is different than the amounts recorded, such differences will impact the provision for income taxes and the effective tax rate in the period in which such determination is made. The Company recognizes tax positions in the consolidated financial statements only when it is more likely than not that the position will be sustained upon examination by the relevant taxing authority. Liabilities are established for differences between positions taken in a tax return and amounts recognized in the consolidated financial statements. The Company reports interest and penalties related to uncertain tax positions, if any, in the provision for income taxes in the consolidated statements of operations and comprehensive income (loss). To the extent that accrued interest and penalties do not ultimately become payable, amounts accrued will be reduced and reflected as a reduction of the overall provision for income taxes in the period that such determination is made.
Revenue Recognition	Revenue Recognition The Company derives revenue from its product sales to distributors and resellers, who in turn sell to original equipment manufacturers or other end customers. The Company recognizes product revenue, at a point in time, upon shipment when it satisfies its performance obligations as evidenced by the transfer of control of its products to customers. The Company measures revenue based on the amount of consideration it expects to be entitled to in exchange for products. Variable consideration is estimated and reflected as an adjustment to the transaction price. The Company determines variable consideration, which consists primarily of price adjustments and product returns by estimating the amount of consideration the Company expects to receive from its customers based on historical experience of price adjustments and product returns. Initial estimates of price adjustments and product returns are updated at the end of each reporting period if additional information becomes available. Changes to the Company’s estimated variable consideration were not material for the periods presented. Since the Company’s performance obligations relate to contracts with a duration of less than one year, it does not disclose the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. The Company’s payment terms vary by contract type and type of customer and generally range from 30 to 60 days from shipment. The Company has also elected to recognize the cost for freight and shipping when control over the products sold passes to customers and revenue is recognized. As a practical expedient, the Company records the incremental costs of obtaining a contract, consisting primarily of sales commissions, when incurred because the amortization period is one year or less. These costs are recorded within sales and marketing expenses. The Company entered into a distribution agreement with MegaChips, whereby the Company appointed MegaChips as the exclusive distributor of its products in Japan. The Company recognizes revenue upon shipment derived from sales of products through MegaChips in the amount of expected payments from parties which purchased the products as adjusted for estimated price concessions and product returns.
Cost of Revenue	Cost of Revenue Cost of revenue consists of wafers acquired from third-party foundries, assembly, packaging, and test cost of the Company’s products paid to third-party contract manufacturers, and personnel and other costs associated with the manufacturing operations of the Company. Cost of revenue also includes depreciation of production equipment, inventory write-downs, amortization of internally developed software, shipping and handling costs, and allocation of overhead and facility costs. The Company also includes credits for rebates received from foundries to cost of revenue.
Research and Development Expenses	Research and Development Expenses Research and development costs consist primarily of personnel cost, material cost, and facilities related expenses, incurred in the course of planned research and development of new products. Research and development costs are expensed as incurred.
Selling, General and Administrative Expenses	Selling, General and Administrative Expenses Selling, general and administrative expenses primarily consist of personnel costs, field application engineering support, travel costs, professional and consulting fees, accounting and audit fees, legal, advertising expenses, and allocated overhead costs. Selling, general and administrative costs are expensed as incurred. Advertising expenses were $0.3 million and $0.2 million, for the years ended December 31, 2019 and 2018.
Stock-Based Compensation	Stock-Based Compensation The Company measures and recognizes compensation expense for all stock-based awards made to employees, based on estimated fair values using the straight-line method over the requisite service period. The Company recognizes forfeitures as they occur. Fair value of grants before IPO On July 20, 2016, certain employees of the Company were granted restricted stock units (“RSUs”), of MegaChips. These units were valued at the fair market price of MegaChips’ common stock on the date of the grant, which was equal to the price of MegaChips’ common stock on the Tokyo Stock Exchange on the grant date. The associated grants were all vested and settled as of June 15, 2018 and no further grants were made by MegaChips. As part of the share based compensation agreement and due to the exercise restriction of 1 year at the time of vesting, the Company promised to advance cash to employees equal to the amount of payroll taxes that were due on vesting instead of issuing the employees restricted shares. The liability associated with the cash expense paid to the employee in lieu of restricted shares was treated as a liability-based award and was valued based on the estimate of the market price of the shares at each reporting date. Adjustments to the fair value of the liability are reported as compensation expense in the consolidated statements of operations and comprehensive income (loss). Fair value of grants after IPO The Company granted RSUs of its own common stock after the completion of its IPO and such grants were valued at the fair market value of the Company’s stock on the date of the grant.
Net Income (Loss) Per Share Attributable to Common Stockholder	Net Income (Loss) Per Share Attributable to Common Stockholder Basic net income (loss) per share attributable to common stockholder is calculated by dividing the net income (loss) attributable to common stockholder by the weighted-average number of shares of common stock outstanding during the period, without consideration for potentially dilutive securities. Diluted net income (loss) per share is computed by dividing the net income (loss) attributable to common stockholder by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net income (loss) per share calculation, the Company does not have any stock issuances that are considered to be potentially dilutive securities. As such, the net income (loss) was attributed entirely to common stockholder. Because the Company has no potentially dilutive securities for the years ended December 31, 2019 and 2018, diluted net income (loss) per share attributable to common stockholder is the same as basic net income (loss) per share attributable to common stockholder for all periods presented.
Comprehensive Income (Loss)	Comprehensive Income (Loss) The Company has no components of other comprehensive income (loss). Therefore, net income (loss) equals comprehensive income (loss) for all periods presented.
Accounting Standards Recently Adopted/Not Yet Adopted	Recently Adopted Accounting Guidance In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) New Accounting Pronouncements Not Yet Adopted In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In August 2018, the FASB issued ASU 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments,

The Company and Summary of Si_3

The Company and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Concentration of Risk, by Risk Factor	The following table discloses these customers’ percentage of revenue for the respective periods: Year Ended December 31, 2019 2018 Customer Quantek Technology Corporation 22 % 20 % Arrow Electronics, Inc. 19 18 Pernas Electronics Co. Ltd. 17 27 At December 31, 2019 and 2018, three customers accounted for 10% or more of accounts receivable, as disclosed below: As of December 31, 2019 2018 Customer Quantek Technology Corporation 32 % 34 % Arrow Electronics, Inc. 26 23 Pernas Electronics Co. Ltd. 12 23
Property, Plant and Equipment Estimated Useful Lives	Depreciation of property and equipment is recognized on a straight-line basis over the estimated useful lives of the respective assets as follows: Lab equipment 3 to 5 years Computer equipment 3 years Furniture and fixtures 5 years Leasehold improvements Shorter of remaining lease term or estimated useful lives of the assets

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Summary of Computation of Basic and Diluted Net Income (Loss) per Share	The following table summarizes the computation of basic and diluted net income (loss) per share attributable to common stockholder of the Company: Year Ended December 31 2019 2018 (in thousands, except per share data) Net loss attributable to common stockholder $ (6,607 ) $ (9,342 ) Weighted-average shares outstanding 10,558 10,000 Weighted average shares used to compute basic and diluted net loss per share 10,558 10,000 Net loss attributable to common stockholders per share, basic and diluted $ (0.63 ) $ (0.93 )

Balance Sheets Components (Tabl

Balance Sheets Components (Tables)	12 Months Ended
	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Schedule of Inventory	Inventory consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Raw materials $ 304 $ 2,723 Work in progress 8,160 14,582 Finished goods 3,447 3,238 Total inventories $ 11,911 $ 20,543
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Advance to suppliers $ 3,338 $ 539 Prepaid expenses 1,279 668 Other current assets 984 2,849 Total prepaid and other current assets $ 5,601 $ 4,056
Schedule of Property and Equipment Net	Property and equipment, net consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Lab Equipment $ 17,376 $ 16,297 Computer Equipment 800 636 Furniture and fixtures 241 241 Construction in Progress 221 221 Leasehold improvements 4,074 4,013 22,712 21,408 Accumulated depreciation (13,424 ) (10,127 ) Total property and equipment, net $ 9,288 $ 11,281
Schedule of Intangible Assets, Net	Intangible assets, net consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Internal use software $ 10,022 $ 9,181 Purchased intangibles 4,793 4,355 14,815 13,536 Accumulated amortization (10,326 ) (5,394 ) Intangible assets, net $ 4,489 $ 8,142
Schedule of Future Amortization Expense for Intangible Assets	The estimated aggregate future amortization expense for intangible assets in development stage and subject to amortization as of December 31, 2019 is summarized as below: (in thousands) 2020 2,513 2021 920 2022 587 2023 469 2024 and beyond — 4,489
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Accrued payroll and related benefits $ 1,880 $ 2,243 Accrued customer rebates 218 216 Accrued interest 72 520 Price adjustment and other revenue reserves 1,222 1,580 Short term lease liability 1,874 — Other accrued expenses 3,176 3,096 Total accrued expenses and other current liabilities $ 8,442 $ 7,655

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Summary of Lease Related Assets and Liabilities	The table below presents the lease-related assets and liabilities recorded on the consolidated balance sheet under the new accounting guidance of ASC Topic 842 as of December 31, 2019: (in thousands) Right-of-use assets $ 9,790 Lease liabilities included in accrued expenses and other current liabilities 1,874 Lease liabilities 7,940 Total operating lease liabilities $ 9,814 Weighted-average remaining lease term (years) 7.1 Weighted-average discount rate (1) 4.1 % (1) Upon adoption of the new lease standard, discount rates used for existing leases were established at January 1, 2019.
Summary of Lease Costs	The table below presents certain information related to the lease costs for operating leases under the new accounting guidance of ASC Topic 842 for the year ended December 31, 2019: (in thousands) Operating lease cost $ 1,419 Short-term lease cost 313 Variable lease cost 494 Total lease cost $ 2,226
Summary of Undiscounted Cash Flows	The table below reconciles the undiscounted cash flows for each of the first five years and total of the remaining years to the operating lease liabilities recorded on the consolidated balance sheet as of December 31, 2019: (in thousands) 2020 $ 2,108 2021 1,409 2022 1,441 2023 1,489 2024 1,532 2025 and beyond 3,212 Total minimum lease payments 11,191 Less: amount of lease payments representing interest (1,377 ) Present value of future minimum lease payments 9,814 Less: current obligations under leases (1,874 ) Long-term lease liabilities $ 7,940
Summary of Future Minimum Lease Payments	As of December 31, 2018, the future minimum lease payments required under non-cancelable operating leases as defined under the previous accounting guidance of ASC Topic 840 were as follows: (in thousands) 2019 $ 1,514 2020 1,485 2021 1,451 2022 1,485 2023 1,533 2024 and beyond 4,877 Total minimum lease payments $ 12,345

Debt Obligations (Tables)

Debt Obligations (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Long Term Debt	Debt obligations as of December 31, 2019 and 2018 consisted of the following: As of December 31, 2019 December 31, 2018 (in thousands) Revolving line of credit: MUFG $ 41,000 $ 41,000 SMBC — 2,000 MegaChips loan — 3,000 Balance 41,000 46,000 Less: Current portion of long-term debt (41,000 ) (46,000 ) Long-term debt $ — $ —
Schedule of Debt Obligations	As of December 31, 2019, debt obligations were as follows (dollars in thousands): Loan Start Date Loan Amount Annual Interest Rate Maturity Date Lender MUFG 12/19/2019 $ 38,000 2.97000 % 6/10/2020 MUFG 8/23/2019 3,000 3.10000 % 2/19/2020 $ 41,000 As of December 31, 2018, debt obligations were as follows (dollars in thousands): Lender Loan Start Date Loan Amount Annual Interest Rate Maturity Date MUFG 6/29/2018 $ 20,000 3.72000 % 6/28/2019 MUFG 8/23/2018 3,000 3.77000 % 8/23/2019 MUFG 9/24/2018 8,000 3.87000 % 9/24/2019 MUFG 12/19/2018 10,000 4.07000 % 12/19/2019 SMBC 12/19/2018 2,000 4.96500 % 12/19/2019 MegaChips 10/1/2018 3,000 3.20838 % 12/31/2018 $ 46,000

Stock-based Compensation (Table

Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Total Stock-Based Compensation Expense	Total stock-based compensation expense for employees recognized in the consolidated statements of operations and comprehensive income (loss) was as follows: Year Ended December 31, 2019 2018 (in thousands) Equity awards Cost of revenue $ 36 $ 19 Research and development 346 526 Selling, general and administrative 997 286 $ 1,379 $ 831 Liability based awards Cost of revenue $ — $ 39 Research and development — 1,062 Selling, general and administrative — 599 $ — $ 1,700 Total stock-based compensation expense $ 1,379 $ 2,531
Schedule of Activity of RSUs Granted	Activity of RSUs granted under the Plan is set forth below: Grant Date Shares Fair Value Outstanding per share Balance at December 31, 2017 77,619 11.89 Granted — — Vested (76,296 ) 11.89 Forfeited (1,323 ) 11.89 Balance at December 31, 2018 — — Granted 3,012,399 13.00 Vested (23,077 ) 13.00 Forfeited — — Balance at December 31, 2019 2,989,322 13.00

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Components of Loss Before Income Taxes	The components of loss before income taxes were as follows: Years Ended December 31, 2019 2018 (in thousands) United States $ (6,485 ) $ (9,205 ) Foreign (130 ) (163 ) $ (6,615 ) $ (9,368 )
Schedule of Components of Income Tax Benefit	The components of income tax benefit were as follows: Years Ended December 31, 2019 2018 (in thousands) United States $ 8 $ 26 Foreign — — $ 8 $ 26
Schedule of Components of Deferred Tax Assets and Liabilities	The material components of the deferred tax assets and liabilities consisted of net operating loss carry-forwards and tax credit carry-forwards. Years Ended December 31, 2019 2018 (in thousands) Deferred tax assets: Accrual, write-down and other $ 2,469 $ 2,931 Depreciation and amortization 76 (2,245 ) Net operating loss and credits carry forwards 42,949 44,810 Total gross deferred tax assets 45,494 45,496 Valuation allowance (45,494 ) (45,496 ) Total net deferred tax assets $ — $ —
Schedule of Reconciliation of Effective Tax Rate	A reconciliation of the Company’s effective tax rate to the statutory U.S. federal rate is as follows: Years Ended December 31, 2019 2018 (in thousands) US Federal Rate 21.0 % 21.0 % R&D Credits (10.9 ) 9.4 Permanent differences and others (18.3 ) 4.2 Change in valuation allowance 8.2 (34.3 ) 0.0 % 0.3 %
Schedule of Reconciliation of Unrecognized Tax Benefit	A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows: December 31, 2019 2018 (in thousands) Beginning balance $ 2,198 $ 1,901 Decrease in balance related to tax position taken during prior periods (14 ) — Increase in balance related to tax position taken during the current period — 297 Ending balance $ 2,184 $ 2,198
Schedule of Tax Years Examination By Major Tax Jurisdictions	As of December 31, 2019, the tax years that remain subject to examination by the major tax jurisdictions under the statute of limitations are as follows: Jurisdiction Earliest Tax Year Subject to Examination U.S. federal 2005 California State 2008

Segment Information and Opera_2

Segment Information and Operations by Geographic Area (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Schedule of Revenue by Country	The following table sets forth revenue by country, based on ship-to destinations, for countries with 10% or more of the Company’s revenue during any of the periods presented: Year Ended December 31, 2019 December 31, 2018 (in thousands) Taiwan $ 39,060 $ 45,107 Hong Kong 16,534 16,204 United States 5,677 6,061 Other 22,803 17,842 Total $ 84,074 $ 85,214

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Related Party Transactions [Abstract]
Summary of Significant Balances, Transactions and Payments with Related Parties	The following is a summary of significant balances, transactions and payments with the related parties. December 31, 2019 December 31, 2018 (in thousands) MegaChips Accounts receivable $ 1,073 $ 1,436 Prepaid expenses and other current assets 18 — Accounts payable 220 194 Loan from MegaChips — 3,000 Year ended December 31, 2019 2018 (in thousands) MegaChips Sales through distribution agreement $ 5,071 $ 5,810 License expense 158 — Commission expense 202 368 Interest expense 94 95 Year Ended December 31, 2019 2018 (in thousands) MegaChips Cash paid for principal $ 3,000 $ — Cash paid for interest 94 95 Cash paid for commissions 202 368 Cash paid for licenses 329 —

Subsequent Events (Tables)

Subsequent Events (Tables)	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Schedule of Unaudited Quarterly Financial Data	On February 19, 2020, the Company repaid its outstanding loan of $3.0 million with MUFG upon maturity. UNAUDITED QUARTERLY FINANCIAL DATA Fiscal Year 2019 Three Months Ended December 31, 2019 September 30, 2019 June 30, 2019 March 31, 2019 (in thousands except per share data) Revenue $ 28,089 $ 25,325 $ 15,843 $ 14,817 Gross profit 13,448 12,147 6,374 7,589 Total operating expenses 12,418 10,647 11,355 10,011 Income (loss) from operations 1,030 1,500 (4,981 ) (2,422 ) Net income (loss) 633 1,079 (5,449 ) (2,870 ) Net income (loss) per share basic and diluted 0.05 0.11 (0.54 ) (0.29 ) Fiscal Year 2018 December 31, 2018 September 30, 2018 June 30, 2018 March 31, 2018 (in thousands except per share data) Revenue $ 22,851 $ 21,694 $ 14,911 $ 25,758 Gross profit 13,751 10,662 6,995 4,797 Total operating expenses 11,661 9,915 10,974 11,445 Income (loss) from operations 2,090 747 (3,979 ) (6,648 ) Net income (loss) 1,650 296 (4,319 ) (6,969 ) Net income (loss) per share basic and diluted 0.17 0.03 (0.43 ) (0.70 )

The Company and Summary of Si_4

The Company and Summary of Significant Accounting Policies - Additional Information (Details)	Nov. 25, 2019USD ($)$ / sharesshares	Nov. 06, 2019	Oct. 16, 2019$ / sharesshares	Dec. 31, 2019USD ($)DistributorCustomer$ / sharesshares	Dec. 31, 2018USD ($)DistributorCustomer$ / sharesshares	Dec. 31, 2019USD ($)$ / sharesshares
Significant Accounting Policies [Line Items]
Stock split			30,000-for-1
Common stock, shares authorized | shares			200,000,000	200,000,000	200,000,000	200,000,000
Common stock, par value | $ / shares			$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Reverse stock split		2-for-3
Fair value, assets, level 1 to level 2 transfers, amount				$ 0	$ 0	$ 0
Fair value, assets, level 2 to level 1 transfers, amount				0	0	0
Fair value, liabilities, level 1 to level 2 transfers, amount				0	0	0
Fair value, liabilities, level 2 to level 1 transfers, amount				0	0	0
Allowances for doubtful accounts				100,000	$ 200,000	100,000
Finance leases				$ 0		$ 0
Exercise restriction at the time of vesting					1 year
Earnings per share, potentially dilutive securities | shares				0	0
Restricted Stock Units RSU
Significant Accounting Policies [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period | shares				3,012,399
Restricted Stock Units RSU | MegaChips
Significant Accounting Policies [Line Items]
Share-based compensation arrangement by share-based payment award, equity instruments other than options, grants in period | shares						0
Selling, General and Administrative Expenses
Significant Accounting Policies [Line Items]
Advertising expenses				$ 300,000	$ 200,000
Purchased Intangibles with Finite Lives
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets				3 years
Revenue | Credit Concentration Risk
Significant Accounting Policies [Line Items]
Number of distributors representing more than 10% of company's revenue | Distributor				3	3
Concentration risk, percentage				10.00%	10.00%
Accounts Receivable | Credit Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk, customer				At December 31, 2019 and 2018, three customers accounted for 10% or more of accounts receivable
Number of customers | Customer				3	3
Level 1
Significant Accounting Policies [Line Items]
Cash balances in bank				$ 28,400,000	$ 7,900,000	$ 28,400,000
Highly liquid money market funds				35,000,000		35,000,000
Other Assets
Significant Accounting Policies [Line Items]
Deferred offering costs				$ 0	$ 0	$ 0
Initial Public Offering
Significant Accounting Policies [Line Items]
Issuance of common stock upon initial public offering net of underwriting discounts and commissions and other offerings costs, Shares | shares	4,945,000
Shares issued price per share | $ / shares	$ 13
Proceeds from public offering, net of underwriting discounts and commissions	$ 56,400,000
Payments for underwriting discounts and commissions	7,900,000
Deferred offering costs	3,400,000
Deferred offering costs reclassified into stockholders' equity	$ 3,400,000
Over-Allotment Option
Significant Accounting Policies [Line Items]
Issuance of common stock upon initial public offering net of underwriting discounts and commissions and other offerings costs, Shares | shares	645,000
MegaChips | SiTime Corporation
Significant Accounting Policies [Line Items]
Percentage of outstanding common stock held				66.80%		66.80%
Minimum
Significant Accounting Policies [Line Items]
Revenue Recognized Payment Terms				30 days
Minimum | Capitalized Internal Use Software
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets				2 years
Minimum | Accounts Receivable | Credit Concentration Risk
Significant Accounting Policies [Line Items]
Concentration risk, percentage				10.00%	10.00%
Maximum
Significant Accounting Policies [Line Items]
Foreign currency remeasurement and transactions gains and losses				$ 100,000	$ 100,000
Warranty reserve balances				$ 100,000	$ 100,000	$ 100,000
Revenue Recognized Payment Terms				60 days
Revenue recognized amortization period term				1 year
Maximum | Capitalized Internal Use Software
Significant Accounting Policies [Line Items]
Estimated useful life of intangible assets				3 years

The Company and Summary of Si_5

The Company and Summary of Significant Accounting Policies - Summary of Customers Percentage Accounted For 10% or More of Revenue and Accounts Receivable (Details) - Credit Concentration Risk	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Revenue
Concentration Risk [Line Items]
Concentration risk, percentage	10.00%	10.00%
Revenue | Pernas Electronics Co. Ltd.
Concentration Risk [Line Items]
Concentration risk, percentage	17.00%	27.00%
Revenue | Arrow Electronics, Inc.
Concentration Risk [Line Items]
Concentration risk, percentage	19.00%	18.00%
Revenue | Quantek Technology Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	22.00%	20.00%
Accounts Receivable | Pernas Electronics Co. Ltd.
Concentration Risk [Line Items]
Concentration risk, percentage	12.00%	23.00%
Accounts Receivable | Arrow Electronics, Inc.
Concentration Risk [Line Items]
Concentration risk, percentage	26.00%	23.00%
Accounts Receivable | Quantek Technology Corporation
Concentration Risk [Line Items]
Concentration risk, percentage	32.00%	34.00%

The Company and Summary of Si_6

The Company and Summary of Significant Accounting Policies - Summary of Estimated Useful Lives of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2019
Lab Equipment | Minimum
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Lab Equipment | Maximum
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	5 years
Computer Equipment
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Furniture and Fixtures
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	5 years
Leasehold Improvements
Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	Shorter of remaining lease term or estimated useful lives of the assets

Recent Accounting Pronounceme_2

Recent Accounting Pronouncements - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Feb. 29, 2016
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Right-of-use assets, net	$ 9,790
Lease liabilities, including current obligations	$ 1,874
Accounting Standards Update 2016-02
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Lease term				1 year
Right-of-use assets, net		$ 7,600
Lease liabilities, including current obligations		$ 10,200
Deferred rent			$ 2,600

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Computation of Basic and Diluted Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Net loss attributable to common stockholder	$ 633	$ 1,079	$ (5,449)	$ (2,870)	$ 1,650	$ 296	$ (4,319)	$ (6,969)	$ (6,607)	$ (9,342)
Weighted-average shares used to compute basic and diluted net loss per share									10,558	10,000
Net loss attributable to common stockholders per share, basic and diluted	$ 0.05	$ 0.11	$ (0.54)	$ (0.29)	$ 0.17	$ 0.03	$ (0.43)	$ (0.70)	$ (0.63)	$ (0.93)

Balance Sheets Components - Sch

Balance Sheets Components - Schedule of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 304	$ 2,723
Work in progress	8,160	14,582
Finished goods	3,447	3,238
Total inventories	$ 11,911	$ 20,543

Balance Sheets Components - Add

Balance Sheets Components - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Inventory write-down		$ 8,000	$ 321	$ 9,165
Sale of inventory	$ 3,000		2,500
Depreciation expense			3,300	3,500
Amortization expense for intangible assets			4,900	3,900
Intangibles Assets not amortized	$ 1,200		$ 2,000	$ 1,200

Balance Sheets Components - S_2

Balance Sheets Components - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Prepaid Expense And Other Assets Current [Abstract]
Advance to suppliers	$ 3,338	$ 539
Prepaid expenses	1,279	668
Other current assets	984	2,849
Total prepaid and other current assets	$ 5,601	$ 4,056

Balance Sheets Components - S_3

Balance Sheets Components - Schedule of Property and Equipment Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 22,712	$ 21,408
Accumulated depreciation	(13,424)	(10,127)
Total property and equipment, net	9,288	11,281
Lab Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	17,376	16,297
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	800	636
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	241	241
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	221	221
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 4,074	$ 4,013

Balance Sheets Components - S_4

Balance Sheets Components - Schedule of Intangible Assets Net (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 14,815	$ 13,536
Accumulated amortization	(10,326)	(5,394)
Intangible assets, net	4,489	8,142
Internal use software
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	10,022	9,181
Purchased intangibles
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 4,793	$ 4,355

Balance Sheets Components - S_5

Balance Sheets Components - Schedule of Future Amortization Expense for Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Finite Lived Intangible Assets Future Amortization Expense Current And Five Succeeding Fiscal Years [Abstract]
2020	$ 2,513
2021	920
2022	587
2023	469
Intangible assets, net	$ 4,489	$ 8,142

Balance Sheets Components - S_6

Balance Sheets Components - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables And Accruals [Abstract]
Accrued payroll and related benefits	$ 1,880	$ 2,243
Accrued customer rebates	218	216
Accrued interest	72	520
Price adjustment and other revenue reserves	1,222	1,580
Short term lease liability	1,874
Other accrued expenses	3,176	3,096
Total accrued expenses and other current liabilities	$ 8,442	$ 7,655

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Lease Disclosure [Line Items]
Prepaid lease payments		$ 1,600
Remaining lease payments		9,814
Rent expense			$ 1,200
Cash paid for operating lease liabilities		3,900
Sublease income		$ 100	300
Leases not yet commenced		Company did not have any leases that had not yet commenced
Subsequent Event
Lease Disclosure [Line Items]
Short-term lease liability payments	$ 800
Lease Equipment
Lease Disclosure [Line Items]
Lease term		10 years
Lease equipment			3,200
Prepaid lease payments			$ 1,600
Remaining lease payments		$ 800
Corporate Headquarters
Lease Disclosure [Line Items]
Operating lease commencement date		Oct. 20, 2016
Lease term expiration date		Dec. 31, 2026
Operating lease, renewal term		5 years
Office Space
Lease Disclosure [Line Items]
Lease term expiration date		May 31, 2021
Lease option to extend		The remaining lease terms vary from few months to 7 years. For its leases the Company has options to extend the lease term for periods varying from one to five years.
Option to extend		true
Office Space | Maximum
Lease Disclosure [Line Items]
Operating lease, renewal term		5 years
Lease term		7 years
Office Space | Minimum
Lease Disclosure [Line Items]
Operating lease, renewal term		1 year

Leases - Summary of Lease Relat

Leases - Summary of Lease Related Assets and Liabilities (Details) $ in Thousands	Dec. 31, 2019USD ($)
Leases [Abstract]
Right-of-use assets, net	$ 9,790
Lease liabilities included in accrued expenses and other current liabilities	1,874
Lease liabilities	7,940
Total operating lease liabilities	$ 9,814
Weighted-average remaining lease term (years)	7 years 1 month 6 days
Weighted-average discount rate	4.10%

Leases - Summary of Lease Costs

Leases - Summary of Lease Costs (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Leases [Abstract]
Operating lease cost	$ 1,419
Short-term lease cost	313
Variable lease cost	494
Total lease cost	$ 2,226

Leases - Summary of Undiscounte

Leases - Summary of Undiscounted Cash Flows (Details) $ in Thousands	Dec. 31, 2019USD ($)
Leases [Abstract]
2020	$ 2,108
2021	1,409
2022	1,441
2023	1,489
2024	1,532
2025 and beyond	3,212
Total minimum lease payments	11,191
Less: amount of lease payments representing interest	(1,377)
Total operating lease liabilities	9,814
Less: current obligations under leases	(1,874)
Long-term lease liabilities	$ 7,940

Leases - Summary of Future Mini

Leases - Summary of Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 1,514
2020	1,485
2021	1,451
2022	1,485
2023	1,533
2024 and beyond	4,877
Total minimum lease payments	$ 12,345

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Millions	Dec. 31, 2019USD ($)
MEMS Wafer Supplier Agreement
Other Commitments [Line Items]
Remaining tooling cost commitment	$ 0.8

Debt Obligations - Additional I

Debt Obligations - Additional Information (Details) - USD ($)	Feb. 19, 2020	Sep. 22, 2017	Sep. 13, 2016	Aug. 31, 2015	Dec. 31, 2019	Dec. 31, 2018	Dec. 19, 2019	Aug. 23, 2019	Sep. 21, 2018	Jun. 29, 2018
Line Of Credit Facility [Line Items]
Weighted average interest rate on short term borrowings outstanding					1.42%	3.69%
Short term portion of total debt					$ 41,000,000	$ 46,000,000
Repayment of outstanding loan					2,000,000	18,000,000
MUFG
Line Of Credit Facility [Line Items]
Short term portion of total debt					41,000,000	41,000,000
MUFG | 3.10000% Loan Maturing on 2/19/2020
Line Of Credit Facility [Line Items]
Short term portion of total debt					3,000,000
SMBC
Line Of Credit Facility [Line Items]
Short term portion of total debt						2,000,000
MegaChips
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity			$ 30,000,000
Short term portion of total debt					0	3,000,000
Interest rate			0.09%
Line of credit facility, remaining borrowing capacity					30,000,000
Debt instrument, term			3 months
Revolving Line of Credit | MUFG
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity				$ 20,000,000						$ 50,000,000
Short term portion of total debt					41,000,000	41,000,000
Interest rate				2.00%
Line of credit facility, remaining borrowing capacity					9,000,000
Revolving Line of Credit | MUFG | Subsequent Event
Line Of Credit Facility [Line Items]
Repayment of outstanding loan	$ 3,000,000
Revolving Line of Credit | MUFG | 3.10000% Loan Maturing on 2/19/2020
Line Of Credit Facility [Line Items]
Short term portion of total debt								$ 3,000,000
Revolving Line of Credit | MUFG | 3.72000% Loan Maturing on 6/10/2020
Line Of Credit Facility [Line Items]
Short term portion of total debt							$ 20,000,000
Revolving Line of Credit | MUFG | 4.07000% Loan Maturing on 6/10/2020
Line Of Credit Facility [Line Items]
Short term portion of total debt							10,000,000
Revolving Line of Credit | MUFG | 3.87000% Loan Maturing on 6/10/2020
Line Of Credit Facility [Line Items]
Short term portion of total debt							$ 8,000,000
Revolving Line of Credit | SMBC
Line Of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity		$ 20,000,000
Short term portion of total debt					0	$ 2,000,000
Interest rate		1.00%
Line of credit facility, remaining borrowing capacity					$ 20,000,000
Debt instrument, maturity		12 months
Financial covenant for minimum net worth		$ 0
Revolving Line of Credit | SMBC | Maximum
Line Of Credit Facility [Line Items]
Debt instrument, principal amount									$ 20,000,000

Debt Obligations - Schedule of

Debt Obligations - Schedule of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Short term portion of total debt	$ 41,000	$ 46,000
Less: Current portion of long-term debt	(41,000)	(46,000)
MUFG
Debt Instrument [Line Items]
Short term portion of total debt	41,000	41,000
SMBC
Debt Instrument [Line Items]
Short term portion of total debt		2,000
MegaChips Loan
Debt Instrument [Line Items]
Short term portion of total debt	$ 0	$ 3,000

Debt Obligations - Schedule o_2

Debt Obligations - Schedule of Debt Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Loan Amount	$ 41,000	$ 46,000
MUFG
Debt Instrument [Line Items]
Loan Amount	$ 41,000	$ 41,000
MUFG | 2.97000% Loan Maturing on 6/10/2020
Debt Instrument [Line Items]
Loan Start Date	Dec. 19, 2019
Loan Amount	$ 38,000
Annual Interest Rate	2.97%
Maturity Date	Jun. 10, 2020
MUFG | 3.10000% Loan Maturing on 2/19/2020
Debt Instrument [Line Items]
Loan Start Date	Aug. 23, 2019
Loan Amount	$ 3,000
Annual Interest Rate	3.10%
Maturity Date	Feb. 19, 2020
MUFG | 3.72000% Loan Maturing on 6/28/2019
Debt Instrument [Line Items]
Loan Start Date		Jun. 29, 2018
Loan Amount		$ 20,000
Annual Interest Rate		3.72%
Maturity Date		Jun. 28, 2019
MUFG | 3.77000% Loan Maturing on 8/23/2019
Debt Instrument [Line Items]
Loan Start Date		Aug. 23, 2018
Loan Amount		$ 3,000
Annual Interest Rate		3.77%
Maturity Date		Aug. 23, 2019
MUFG | 3.87000% Loan Maturing on 9/24/2019
Debt Instrument [Line Items]
Loan Start Date		Sep. 24, 2018
Loan Amount		$ 8,000
Annual Interest Rate		3.87%
Maturity Date		Sep. 24, 2019
MUFG | 4.07000% Loan Maturing on 12/19/2019
Debt Instrument [Line Items]
Loan Start Date		Dec. 19, 2018
Loan Amount		$ 10,000
Annual Interest Rate		4.07%
Maturity Date		Dec. 19, 2019
SMBC
Debt Instrument [Line Items]
Loan Amount		$ 2,000
SMBC | 4.96500% Loan Maturing on 12/19/2019
Debt Instrument [Line Items]
Loan Start Date		Dec. 19, 2018
Loan Amount		$ 2,000
Annual Interest Rate		4.965%
Maturity Date		Dec. 19, 2019
MegaChips
Debt Instrument [Line Items]
Loan Amount	$ 0	$ 3,000
MegaChips | 3.20838% Loan Maturing on 12/31/2018
Debt Instrument [Line Items]
Loan Start Date		Oct. 1, 2018
Loan Amount		$ 3,000
Annual Interest Rate		3.20838%
Maturity Date		Dec. 31, 2018

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Oct. 16, 2019	Dec. 31, 2018
Equity [Abstract]
Common stock, shares authorized	200,000,000	200,000,000	200,000,000
Common stock, par value	$ 0.0001	$ 0.0001	$ 0.0001
Common stock, voting rights	one vote

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended	19 Months Ended
	Nov. 30, 2019	Dec. 31, 2019	Dec. 31, 2019	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unamortized compensation expense related to unvested stock awards		$ 37.8	$ 37.8
Unamortized compensation cost expected to be recognized, Weighted average period		4 years 4 months 24 days
Restricted Stock Units RSU
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant date fair value		$ 13	$ 13	$ 11.89
Awards granted		3,012,399
Restricted Stock Units RSU | MegaChips
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards granted			0
Time-based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Awards granted		3,000,000
Time-based Restricted Stock Awards | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting schedule		2 years
Time-based Restricted Stock Awards | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting schedule		5 years
2019 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, capital shares reserved for future issuance	3,400,000	300,000	300,000
Vesting schedule	4 years
Restricted Stock Unit Plan | Restricted Stock Units RSU | MegaChips
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting schedule		2 years
Number of shares authorized for grant		339,911	339,911
Grant date fair value		$ 11.89	$ 11.89
Awards granted			0

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Total Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 1,379	$ 2,531
Equity Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	1,379	831
Equity Awards | Cost of Revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	36	19
Equity Awards | Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	346	526
Equity Awards | Selling, General and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 997	286
Liability Based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		1,700
Liability Based Awards | Cost of Revenue
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		39
Liability Based Awards | Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		1,062
Liability Based Awards | Selling, General and Administrative Expenses
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 599

Stock-based Compensation - Sc_2

Stock-based Compensation - Schedule of Activity of RSUs Granted (Details) - Restricted Stock Units RSU - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares Outstanding, Beginning Balance		77,619
Shares Outstanding, Granted	3,012,399
Shares Outstanding, Vested	(23,077)	(76,296)
Shares Outstanding, Forfeited		(1,323)
Shares Outstanding, Ending Balance	2,989,322
Grant Date Fair Value per share, Beginning Balance		$ 11.89
Grant Date Fair Value per share, Granted	$ 13
Grant Date Fair Value per share, Vested	13	11.89
Grant Date Fair Value per share, Forfeited		$ 11.89
Grant Date Fair Value per share, Ending Balance	$ 13

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
United States	$ (6,485)	$ (9,205)
Foreign	(130)	(163)
Loss before income taxes	$ (6,615)	$ (9,368)

Income Taxes - Schedule of Co_2

Income Taxes - Schedule of Components of Income Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
United States	$ 8	$ 26
Income tax benefit	$ 8	$ 26

Income Taxes - Schedule of Co_3

Income Taxes - Schedule of Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Accrual, write-down and other	$ 2,469	$ 2,931
Depreciation and amortization, assets	76
Depreciation and amortization, liabilities		(2,245)
Net operating loss and credits carry forwards	42,949	44,810
Total gross deferred tax assets	45,494	45,496
Valuation allowance	$ (45,494)	$ (45,496)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Federal net operating loss carry-forwards	$ 156,500,000	$ 160,700,000
State net operating loss carry-forwards	63,700,000	63,900,000
Foreign net operating loss carry-forwards	$ 1,300,000	0
Federal net operating loss carry-forwards expiration year	2025
State net operating loss carry-forwards expiration year	2028
Foreign net operating loss carry-forwards expiration year	2028
Federal research and development tax credit carry-forwards	$ 3,900,000	4,600,000
State research and development tax credit carry-forwards	$ 3,600,000	4,100,000
Expiration of federal tax credits	2025
Unrecognized tax benefits	$ 2,184,000	$ 2,198,000	$ 1,901,000
Maximum
Income Tax Contingency [Line Items]
Change in valuation allowance	$ 100,000

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
US Federal Rate	21.00%	21.00%
R&D Credits	(10.90%)	9.40%
Permanent differences and others	(18.30%)	4.20%
Change in valuation allowance	8.20%	(34.30%)
Effective income tax rate	0.00%	0.30%

Income Taxes - Schedule of Re_2

Income Taxes - Schedule of Reconciliation of Unrecognized Tax Benefit (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Beginning balance	$ 2,198	$ 1,901
Decrease in balance related to tax position taken during prior periods	(14)
Increase in balance related to tax position taken during the current period		297
Ending balance	$ 2,184	$ 2,198

Income Taxes - Schedule of Tax

Income Taxes - Schedule of Tax Years Examination By Major Tax Jurisdictions (Details)	12 Months Ended
	Dec. 31, 2019
U.S. Federal
Income Tax Examination [Line Items]
Earliest Tax Year Subject to Examination	2005
Foreign Tax Authority | California State
Income Tax Examination [Line Items]
Earliest Tax Year Subject to Examination	2008

401(k) Plan - Additional Inform

401(k) Plan - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Defined Contribution Pension And Other Postretirement Plans Disclosure [Abstract]
Maximum pre-tax contribution per employee	90.00%
Matching contributions	$ 0.6	$ 0.6

Segment Information and Opera_3

Segment Information and Operations by Geographic Area - Additional Information (Details) - Segment	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting [Abstract]
Number of reportable segments	1
Percentage of long lived assets	97.00%	97.00%

Segment Information and Opera_4

Segment Information and Operations by Geographic Area - Schedule of Revenue by Country (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenue	$ 28,089	$ 25,325	$ 15,843	$ 14,817	$ 22,851	$ 21,694	$ 14,911	$ 25,758	$ 84,074	$ 85,214
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue									84,074	85,214
Taiwan | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue									39,060	45,107
Hong Kong | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue									16,534	16,204
United States | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue									5,677	6,061
Other | Revenue from Contract with Customer Benchmark | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Revenue									$ 22,803	$ 17,842

Related Party Transactions - Su

Related Party Transactions - Summary of Significant Balances, Transactions and Payments with Related Parties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Related party accounts receivable	$ 1,073	$ 1,436
Related party loan obligations		3,000
MegaChips
Related Party Transaction [Line Items]
Related party accounts receivable	1,073	1,436
Prepaid expenses and other current assets	18
Accounts payable	220	194
Related party loan obligations		3,000
Sales through distribution agreement	5,071	5,810
License expense	158
Commission expense	202	368
Interest expense	94	95
Cash paid for principal	3,000
Cash paid for interest	94	95
Cash paid for commissions	202	$ 368
Cash paid for licenses	$ 329

Subsequent Events - Additional

Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands	Feb. 19, 2020	Dec. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Repayment of outstanding loan		$ 2,000	$ 18,000
Revolving Line of Credit | MUFG | Subsequent Event
Subsequent Event [Line Items]
Repayment of outstanding loan	$ 3,000

Subsequent Events - Schedule of

Subsequent Events - Schedule of Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Data [Abstract]
Revenue	$ 28,089	$ 25,325	$ 15,843	$ 14,817	$ 22,851	$ 21,694	$ 14,911	$ 25,758	$ 84,074	$ 85,214
Gross profit	13,448	12,147	6,374	7,589	13,751	10,662	6,995	4,797	39,558	36,205
Total operating expenses	12,418	10,647	11,355	10,011	11,661	9,915	10,974	11,445	44,431	43,995
Income (loss) from operations	1,030	1,500	(4,981)	(2,422)	2,090	747	(3,979)	(6,648)	(4,873)	(7,790)
Net income (loss)	$ 633	$ 1,079	$ (5,449)	$ (2,870)	$ 1,650	$ 296	$ (4,319)	$ (6,969)	$ (6,607)	$ (9,342)
Net loss attributable to common stockholders per share, basic and diluted	$ 0.05	$ 0.11	$ (0.54)	$ (0.29)	$ 0.17	$ 0.03	$ (0.43)	$ (0.70)	$ (0.63)	$ (0.93)

Schedule II - Valuation and Q_2

Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts Receivables
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 168	$ 125
Additions Charged to Expenses or Other Accounts		43
Deductions Credited to Expenses or Other Accounts	(39)
Balance at End of Period	129	168
Deferred Tax Valuation Allowance
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	45,496	42,308
Additions Charged to Expenses or Other Accounts	(2)	3,188
Balance at End of Period	$ 45,494	$ 45,496