GenMark Diagnostics (GNMK) 10-Q 30 Oct 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Jul. 26, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	GenMark Diagnostics, Inc.
Entity Central Index Key	1,487,371
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		55,955,284

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 25,005,000	$ 26,754,000
Short-term marketable securities	17,657,000	45,236,000
Accounts receivable, net of allowances of $75 and $2,754, respectively	9,858,000	10,676,000
Inventories	11,254,000	10,949,000
Prepaid expenses and other current assets	1,894,000	2,216,000
Total current assets	65,668,000	95,831,000
Property and equipment, net	21,873,000	22,581,000
Intangible assets, net	2,170,000	2,624,000
Restricted cash	758,000	758,000
Other long-term assets	562,000	505,000
Total assets	91,031,000	122,299,000
Current liabilities:
Accounts payable	8,242,000	11,171,000
Accrued compensation	6,987,000	5,419,000
Current portion of long-term debt	0	7,927,000
Other current liabilities	2,302,000	3,226,000
Total current liabilities	17,531,000	27,743,000
Deferred rent	2,952,000	3,059,000
Long-term debt	28,730,000	20,099,000
Other noncurrent liabilities	112,000	241,000
Total liabilities	49,325,000	51,142,000
Stockholders' equity:
Preferred stock, $0.0001 par value; 5,000 authorized, none issued	0	0
Common stock, $0.0001 par value; 100,000 authorized; 55,955 and 55,066 shares issued and outstanding, respectively	6,000	6,000
Additional paid-in capital	497,018,000	487,525,000
Accumulated deficit	(455,322,000)	(416,383,000)
Accumulated other comprehensive income	4,000	9,000
Total stockholders’ equity	41,706,000	71,157,000
Total liabilities and stockholders’ equity	$ 91,031,000	$ 122,299,000

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Accounts receivable - net of allowance	$ 75	$ 2,754
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, authorized	5,000,000	5,000,000
Preferred stock, issued	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized	100,000,000	100,000,000
Common stock, issued	55,955,000	55,066,000
Common stock, outstanding	55,955,000	55,066,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenue:
Product revenue	$ 15,713	$ 11,552	$ 51,156	$ 36,313
License and other revenue	82	51	225	184
Total revenue	15,795	11,603	51,381	36,497
Cost of revenue	10,165	7,400	37,172	21,227
Gross profit	5,630	4,203	14,209	15,270
Operating expenses:
Sales and marketing	5,375	5,121	15,964	14,974
General and administrative	4,718	3,565	13,398	11,553
Research and development	6,105	10,248	22,007	34,297
Total operating expenses	16,198	18,934	51,369	60,824
Loss from operations	(10,568)	(14,731)	(37,160)	(45,554)
Other income (expense):
Interest income	188	247	577	353
Interest expense	(661)	(1,009)	(2,246)	(2,270)
Other income (expense)	53	76	(49)	227
Total other income (expense)	(420)	(686)	(1,718)	(1,690)
Loss before provision for income taxes	(10,988)	(15,417)	(38,878)	(47,244)
Income tax expense (benefit)	5	(9)	59	68
Net loss	$ (10,993)	$ (15,408)	$ (38,937)	$ (47,312)
Net loss per share, basic and diluted	$ (0.20)	$ (0.28)	$ (0.70)	$ (0.95)
Weighted average number of shares outstanding, basic and diluted	55,847	54,726	55,535	49,908
Other comprehensive loss:
Net loss	$ 10,993	$ 15,408	$ 38,937	$ 47,312
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	49	51	29	145
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	4	(9)	26	(24)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	53	42	55	121
Other Comprehensive Income (Loss), Net of Tax	$ (10,940)	$ (15,366)	$ (38,882)	$ (47,191)

Condensed Consolidated Statem_2

Condensed Consolidated Statement of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Operating activities:
Net loss	$ 38,937,000	$ 47,312,000
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,281,000	3,811,000
Net amortization/(accretion) of premiums/discounts on investments	(110,000)	4,000
Amortization of deferred debt issuance costs	725,000	891,000
Stock-based compensation	8,895,000	8,386,000
Provision for bad debt	24,000	51,000
Non-cash inventory adjustments	1,061,000	911,000
Other non-cash adjustments	(62,000)	(190,000)
Changes in operating assets and liabilities:
Accounts receivable	797,000	1,272,000
Inventories	(3,847,000)	(4,813,000)
Prepaid expenses and other assets	384,000	(767,000)
Other long-term assets	0	(16,000)
Accounts payable	(3,408,000)	(1,468,000)
Accrued compensation	1,053,000	(452,000)
Other current and non-current liabilities	(756,000)	(913,000)
Net cash used in operating activities	(28,900,000)	(40,605,000)
Investing activities:
Purchases of property and equipment, net	(1,060,000)	(3,816,000)
Payments to Acquire Intangible Assets	0	(500,000)
Purchases of marketable securities	(28,785,000)	(56,525,000)
Proceeds from sales of marketable securities	0	13,896,000
Maturities of marketable securities	56,500,000	8,500,000
Net cash provided by (used in) investing activities	26,655,000	(38,445,000)
Financing activities:
Proceeds from issuance of common stock	535,000	86,835,000
Costs incurred in conjunction with public offering	0	(5,469,000)
Principal repayment of borrowings	(68,000)	(6,123,000)
Proceeds from borrowings	0	15,000,000
Payments associated with debt issuance	(20,000)	(187,000)
Proceeds from stock option exercises	(22,000)	(213,000)
Net cash provided by financing activities	469,000	90,269,000
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	27,000	(17,000)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(1,749,000)	11,202,000
Cash, cash equivalents, and restricted cash at beginning of year	27,512,000	16,717,000
Cash, cash equivalents, and restricted cash at end of period	25,763,000
Non-cash investing and financing activities:
Transfer of systems (from) to property and equipment into (from) inventory	2,477,000	(3,438,000)
Property and equipment included in accounts payable	746,000	330,000
Supplemental cash flow information:
Cash paid for income taxes, net	133,000	58,000
Cash paid for interest	1,517,000	1,143,000
Intellectual property acquisitions included in other current liabilities	$ 0	$ 0

Organization and Basis of Prese

Organization and Basis of Presentation (Notes)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation GenMark Diagnostics, Inc., the Company or GenMark, was formed by Osmetech plc as a Delaware corporation in February 2010, and had no operations prior to its initial public offering, which was completed in June 2010. The Company is a provider of automated, multiplex molecular diagnostic testing systems that detect and measure DNA and RNA targets to diagnose disease and optimize patient treatment. Basis of Presentation and Principles of Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles, or U.S. GAAP, and applicable regulations of the U.S. Securities and Exchange Commission, or the SEC, and should be read in conjunction with the audited financial statements included in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the SEC on February 27, 2018. These unaudited condensed consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. These adjustments are of a normal, recurring nature. Interim period operating results may not be indicative of the operating results for the full year or any future period. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company has experienced net losses and negative cash flows from operating activities since its inception and had an accumulated deficit of $455,322,000 as of September 30, 2018 . The Company's ability to transition to profitable operations is dependent upon achieving a level of revenues adequate to support its cost structure through expanding its product offerings and consequently increasing its product revenues. As of September 30, 2018 , the Company had available cash, cash equivalents, and marketable securities of $42,662,000 and working capital of $48,137,000 available to fund future operations. The Company has prepared cash flow forecasts which indicate, based on the Company's current cash resources available and working capital, that the Company will have sufficient resources to fund its operations for at least one year after the date the financial statements are issued. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and the notes thereto. The Company’s significant estimates included in the preparation of the financial statements are related to accounts receivable, inventories, property and equipment, intangible assets, employee-related compensation accruals, warranty liabilities, tax valuation accounts and stock-based compensation. Actual results could differ from those estimates. Segment Information The Company currently operates in one reportable business segment, which encompasses the development, manufacturing, sales and support of instruments and molecular tests based on its proprietary eSensor® detection technology. Substantially all of the Company’s operations and assets are in the United States. Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or the FASB, or other standard setting bodies that the Company adopts as of the specified effective date. In June 2018, the FASB issued Accounting Standards Update, or ASU 2018-07, Compensation - Stock Compensation (Topic 718) , which simplifies the accounting for non-employee share-based payment transactions. The new standard expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees. ASU 2018-07 is effective for fiscal years beginning after December 15, 2018 (including interim periods within that fiscal year), with early adoption permitted. The Company adopted the new standard in the second quarter of 2018 and determined that the application of the new standard did not have a material impact on the Company's unaudited condensed consolidated financial statements. In November 2016, the FASB issued ASU, 2016-18, Statement of Cash Flows (Topic 230) Restricted Cash , which requires amounts generally described as restricted cash and restricted cash equivalents to be included in the cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for fiscal years beginning after December 15, 2017 (including interim periods within those periods) using a retrospective transition method for each period presented, with early adoption permitted. The Company adopted the new standard in the first quarter of 2018 using the retrospective transition method resulting in an increase in the beginning and ending cash balance of $758,000 for each period presented. In February 2016, the FASB issued ASU 2016-02, Leases, which outlines a comprehensive lease accounting model and supersedes the current lease guidance. The new guidance requires lessees to recognize lease liabilities and corresponding right-of-use assets for all leases with lease terms of greater than 12 months. It also changes the definition of a lease and expands the disclosure requirements of lease arrangements. The new guidance must be adopted using the modified retrospective approach and will be effective for the Company starting in the first quarter of 2019, with early adoption permitted. The Company believes that adoption of this guidance will modify its analysis and disclosures of lease agreements because operating agreements are a significant portion of the Company's total lease commitments. The Company intends to adopt this guidance in the first quarter of 2019 and is in the process of determining the effects the adoption of this guidance will have on its unaudited condensed consolidated financial statements. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), an updated standard on revenue recognition. The new standard provides enhancements to the quality and consistency of how revenue is reported under the principle that revenue should be recognized in an amount that reflects the consideration to which the Company expects to be entitled in exchange for the transfer of promised goods or services. The Company adopted the new standard using the modified retrospective transition method. The cumulative effect of applying the new standard as of January 1, 2018 resulted in a net increase in opening retained earnings of $736,000 to capitalize certain costs to obtain sales contracts. The Company recognized $400,000 in expense related to the amortization of capitalized contract costs during the nine months ended September 30, 2018. Aside from this adjustment to beginning retained earnings and the related amortization of expense during the nine months ended September 30, 2018, the application of this standard did not have a material impact on the Company's unaudited condensed consolidated financial statements as of and for the nine months ended September 30, 2018. Revenue The Company recognizes revenue from operations through the sale of products and other services. Product revenue is comprised of the sale of diagnostic tests and instruments. Revenue is recognized when control of products and services is transferred to the customer in an amount that reflects the consideration that the Company expects to receive from the customer in exchange for those products and services. This process involves identifying the contract with the customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers a performance obligation satisfied once it has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The Company recognizes revenue for satisfied performance obligations only when it determines there are no uncertainties regarding payment terms or transfer of control. Revenue from product sales is recognized generally upon shipment to the end customer, which is when control of the product is deemed to be transferred. Invoicing typically occurs upon shipment and the term between invoicing and when payment is due is not significant. Revenue from instrument services is recognized as the services are rendered, typically evenly over the contract term. Revenue is recorded net of discounts and sales taxes collected on behalf of governmental authorities. Employee sales commissions are recorded as selling, general and administrative expenses when incurred or amortized over the estimated contract term when resulting from new contract acquisition efforts. The Company allocates contract price to each performance obligation in proportion to its stand-alone selling price. The stand-alone selling price is determined by the Company's best estimate of stand-alone selling price using average selling prices over a rolling 12-month period along with a specific assessment of any unique circumstances of the contract. For those products for which there is limited sales history, the Company makes price determination based on similar product sales data. The following table represents disaggregated revenue by source (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Revenue Source: ePlex product revenue $ 6,743 $ 2,311 $ 25,757 $ 4,385 XT-8 product revenue 8,970 9,241 25,399 31,928 Total product revenue 15,713 11,552 51,156 36,313 License and other revenue 82 51 225 184 Total revenue $ 15,795 $ 11,603 $ 51,381 $ 36,497 Cash, Cash Equivalents and Marketable Securities Cash and cash equivalents consist of cash on deposit with banks, money market instruments and certificates of deposit with original maturities of three months or less at the date of purchase. Marketable securities consist of certificates of deposits that mature in greater than three months. Marketable securities are accounted for as "available-for-sale" with the carrying amounts reported in the balance sheets stated at cost, which approximates their fair market value, with unrealized gains and losses, if any, reported as a separate component of stockholders' equity and included in comprehensive loss. Restricted Cash Restricted cash represents amounts designated for uses other than current operations and comprised $758,000 as of September 30, 2018 and December 31, 2017, held as security for the Company’s letter of credit with Banc of California. Receivables Accounts receivable consist of amounts due to the Company for sales to customers and are recorded net of an allowance for doubtful accounts. The allowance for doubtful accounts is determined based on an assessment of the collectability of specific customer accounts, the aging of accounts receivable, and a reserve for unknown items based upon the Company’s historical experience. Product Warranties The Company generally offers a one year warranty for its instruments sold to customers and typically up to a sixty day warranty for consumables. Factors that affect the Company’s warranty reserves include the number of units sold, historical and anticipated rates of warranty repairs, and the cost per repair. The Company periodically assesses the adequacy of its warranty reserve and adjusts the amount as appropriate. Intangible Assets Intangible assets comprise licenses or sublicenses to technology covered by patents owned by third parties, and are amortized on a straight-line basis over the expected useful lives of these assets, which is generally ten years. Amortization of licenses typically begins upon the Company obtaining access to the licensed technology and is recorded in cost of revenues for licenses supporting commercialized products. The amortization of licenses to technology supporting products in development is recorded in research and development expenses. Impairment of Long-Lived Assets The Company assesses the recoverability of long-lived assets, including intangible assets, by periodically evaluating the carrying value whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. If impairment is indicated, the Company writes down the carrying value of the asset to its estimated fair value. This fair value is primarily determined based on estimated discounted cash flows. Inventories Inventories are stated at the lower of cost (first-in, first-out) or net realizable value and include direct labor, materials, and manufacturing overhead. The Company periodically reviews inventory for evidence of slow-moving or obsolete parts, and writes inventory down to net realizable value, as needed. This write-down is based on management’s review of inventories on hand, compared to estimated future usage and sales, shelf-life assumptions, and assumptions about the likelihood of obsolescence. If actual market conditions are less favorable than those projected by the Company, additional inventory write-downs may be required. Inventory impairment charges establish a new cost basis for inventory and charges are not reversed subsequently to income, even if circumstances later suggest that increased carrying amounts are recoverable. Property and Equipment, net Property, equipment and leasehold improvements are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets, which are identified below. Repair and maintenance costs are expensed as incurred. Machinery and laboratory equipment 3 - 5 years Instruments 4 - 5 years Office equipment 3 - 7 years Leasehold improvements over the shorter of the remaining life of the lease or the useful economic life of the asset Income Taxes Current income tax expense is the amount of income taxes expected to be payable for the current year. A deferred income tax liability or asset is established for the expected future tax consequences resulting from the differences in financial reporting and tax bases of assets and liabilities. A valuation allowance is provided if it is more likely than not that some or all of the deferred tax assets will not be realized. A full valuation allowance has been recorded against the Company’s net deferred tax assets due to the uncertainty surrounding the Company’s ability to utilize these assets in the future. The Company provides for uncertain tax positions when such tax positions do not meet the recognition thresholds or measurement standards prescribed by the authoritative guidance on income taxes. Amounts for uncertain tax positions are adjusted in periods when new information becomes available or when positions are effectively settled. The Company recognizes accrued interest related to uncertain tax positions as a component of income tax expense. A tax position that is more likely than not to be realized is measured at the largest amount of tax benefit that is greater than 50% likely of being realized upon settlement with the taxing authority that has full knowledge of all relevant information. Measurement of a tax position that meets the more likely than not threshold considers the amounts and probabilities of the outcomes that could be realized upon settlement using the facts, circumstances and information available at the reporting date.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation The Company recognizes stock-based compensation expense related to stock options, restricted stock awards, restricted stock units, and market-based stock units granted to employees, directors and non-employee advisors in exchange for services under the Company's 2010 Equity Incentive Plan, or the 2010 Plan, and employee stock purchases under the Company's Amended and Restated 2013 Employee Stock Purchase Plan, or the ESPP. Employee participation in the 2010 Plan is at the discretion of the Compensation Committee of the Board of Directors of the Company. Each equity award grant reduces the number of shares available for grant under the 2010 Plan. Stock-based compensation expense is recorded in cost of sales, sales and marketing, research and development, and/or general and administrative expenses based on the employee's respective function. During the nine months ended September 30, 2018 and 2017 , aggregate stock-based compensation expense was $8,895,000 and $8,386,000 , respectively. Stock Options The fair value of stock options granted is derived from the Black-Scholes Option Pricing Model, which uses several judgment-based variables to calculate the expense. The inputs include the expected term of the stock option, the expected volatility and other factors. • Expected Term. Expected term represents the period that the stock-based awards are expected to be outstanding and is determined by using the simplified method. • Expected Volatility . Expected volatility represents the estimated volatility in the Company’s stock price over the expected term of the stock option and is determined by review of the Company’s and similar companies’ historical experience. • Expected Dividend . The Black-Scholes Option Pricing Model calls for a single expected dividend yield as an input. The Company has assumed no dividends as it has never paid dividends and has no current plans to do so. • Risk-Free Interest Rate. The risk-free interest rate used in the Black-Scholes Option Pricing Model is based on published U.S. Treasury rates in effect at the time of grant for periods corresponding with the expected term of the option. All stock options granted under the 2010 Plan are exercisable at a per share price equal to the closing quoted market price of a share of the Company’s common stock on the NASDAQ Global Market on the grant date and generally vest over a period of four years. Stock options are generally exercisable for a period of up to ten years after grant and are typically forfeited if employment is terminated before the options vest. The following table summarizes stock option activity during the nine months ended September 30, 2018 : Number of Shares Weighted Average Exercise Price Outstanding at December 31, 2017 2,490,465 $ 9.59 Granted — $ — Exercised (5,042 ) $ 4.33 Cancelled (40,153 ) $ 11.20 Outstanding at September 30, 2018 2,445,270 $ 9.58 Vested and expected to vest at September 30, 2018 2,443,432 $ 9.58 Exercisable at September 30, 2018 2,383,339 $ 9.49 Options that were exercisable as of September 30, 2018 had a remaining weighted average contractual term of 4.38 years, and an aggregate intrinsic value of $1,729,000 . As of September 30, 2018 , there were 2,445,270 stock options outstanding, which had a remaining weighted average contractual term of 4.43 years and an aggregate intrinsic value of $1,734,000 . No stock options were granted during the nine months ended September 30, 2018 . Restricted Stock Awards and Units Restricted stock awards or units may be granted at the discretion of the compensation committee of the board of directors under the 2010 Plan in connection with the hiring or retention of personnel and are subject to certain conditions. In March 2013, the Company transitioned to granting restricted stock units under the 2010 Plan in lieu of granting restricted stock awards. Restricted stock awards or units granted under the 2010 Plan generally vest over a period of between one and four years and are typically forfeited if employment is terminated before the restricted stock awards or units vest. The compensation expense related to the restricted stock awards or units is calculated as the fair market value of the Company's stock on the grant date and is adjusted for estimated forfeitures. Restrictions expire after the grant date in accordance with specific provisions in the applicable award agreement. The Company’s restricted stock unit activity for the nine months ended September 30, 2018 and 2017 was as follows: Restricted Stock Units Number of Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2017 2,073,440 $ 9.14 Granted 1,726,126 $ 4.51 Vested (750,310 ) $ 9.54 Cancelled (137,308 ) $ 8.83 Unvested at September 30, 2018 2,911,948 $ 6.30 As of September 30, 2018 , there was $12,780,000 of unrecognized compensation cost related to unvested restricted stock units, which is expected to be recognized over a weighted average period of 2.58 years. The total fair value of restricted stock units that vested during the nine months ended September 30, 2018 and 2017 was $4,392,000 and $4,181,000 , respectively. Market-Based Stock Units The Company issued market-based stock units in February 2018 , 2017 , and 2016 , which may result in the recipient receiving shares of stock equal to 200% of the target number of units granted. The vesting and issuance of Company stock depends on the Company's stock performance as compared to the NASDAQ Composite Index over the three -year period following the grant, subject to the recipient's continued service with the Company. As of September 30, 2018 , there was $1,451,000 of unrecognized stock-based compensation expense related to market-based stock unit awards, which is expected to be recognized over a weighted average period of 1.53 years. The Company’s market-based stock unit activity for the nine months ended September 30, 2018 was as follows: Market-Based Stock Units Number of Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2017 233,743 $ 10.88 Target units granted 320,000 $ 7.19 Unvested at September 30, 2018 553,743 $ 8.75 The fair value of these market-based stock units was estimated on the date of grant using the Monte Carlo Simulation Valuation Model, which estimates the potential outcome of achieving the market condition based on simulated future stock prices, with the following assumptions for the nine months ended September 30, 2018 : Nine Months Ended September 30, 2018 2017 Expected volatility 65 % 54 % Risk-free interest rate 2.40 % 1.50 % Expected dividend — % — % Weighted average fair value $ 7.19 $ 13.82 Employee Stock Purchase Plan The Company's stockholders approved the ESPP in May 2013. A total of 650,000 shares of the Company’s common stock were originally reserved for issuance under the ESPP, which permits eligible employees to purchase common stock at a discount through payroll deductions. In March 2018, the Company’s Board of Directors approved the amendment and restatement of the ESPP to increase the total number of shares authorized for issuance under the ESPP from 650,000 shares to 1,750,000 shares, which was approved by the Company’s stockholders at the Company’s 2018 Annual Stockholder Meeting held on May 24, 2018. The price at which stock is purchased under the ESPP is equal to 85% of the fair market value of the Company's common stock on the first or the last day of the offering period, whichever is lower. Generally, each offering under the ESPP will be for a period of six months as determined by the Company's Board of Directors; provided that no offering period may exceed 27 months . Employees may invest up to 10% of their qualifying gross compensation through payroll deductions. In no event may an employee purchase more than 1,500 shares of common stock during any six-month offering period. As of September 30, 2018 , there were 1,059,213 shares of common stock available for issuance under the ESPP. The ESPP is a compensatory plan as defined by the authoritative guidance for stock compensation; therefore, stock-based compensation expense related to the ESPP has been recorded during the nine months ended September 30, 2018 . Stock-Based Compensation Expense Recognition Stock-based compensation was recognized in the unaudited condensed consolidated statements of comprehensive loss as follows (in thousands): Three Months Ended Nine Months Ended 2018 2017 2018 2017 Cost of revenue $ 230 $ 124 $ 637 $ 398 Sales and marketing 719 703 2,059 2,061 Research and development 605 693 1,890 2,121 General and administrative 1,542 1,264 4,309 3,806 Total stock-based compensation expense $ 3,096 $ 2,784 $ 8,895 $ 8,386 Stock-based compensation capitalized during the periods presented was not material and there was no unrecognized tax benefit related to stock-based compensation for the nine months ended September 30, 2018 and 2017 .

Net Loss per Common Share (Note

Net Loss per Common Share (Notes)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Net Loss per Common Share	Net Loss per Common Share Basic net loss per share is calculated by dividing loss available to stockholders of the Company's common stock (the numerator) by the weighted average number of shares of the Company's common stock outstanding during the period (the denominator). Shares issued during the period and shares reacquired during the period are weighted for the portion of the period that they were outstanding. Diluted loss per share is calculated in a similar way to basic loss per share except that the denominator is increased to include the number of additional shares that would have been outstanding if the dilutive potential shares had been issued, unless the effect would be anti-dilutive. The computations of diluted net loss per share for the three and nine month periods ended September 30, 2018 and 2017 did not include the effects of the following stock options and other equity awards which were outstanding as of the end of each period because the inclusion of these securities would have been anti-dilutive (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Options outstanding to purchase common stock 2,445 2,526 2,445 2,526 Other unvested equity awards 3,466 2,466 3,466 2,466 Total 5,911 4,992 5,911 4,992

Condensed Consolidated Financia

Condensed Consolidated Financial Statement Details (Notes)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed Consolidated Financial Statement Details	Condensed Consolidated Financial Statement Details The following tables show the Company's unaudited condensed consolidated financial statement details as of September 30, 2018 and December 31, 2017 (in thousands): Inventory September 30, 2018 December 31, 2017 Raw materials $ 2,805 $ 4,534 Work-in-process 4,037 3,638 Finished goods 4,412 2,777 Total inventories $ 11,254 $ 10,949 Property and Equipment, Net September 30, 2018 December 31, 2017 Property and equipment — at cost: Machinery and laboratory equipment $ 15,296 $ 13,762 Instruments 14,778 13,347 Office equipment 2,146 1,948 Leasehold improvements 10,612 10,480 Total property and equipment — at cost 42,832 39,537 Less: accumulated depreciation (20,959 ) (16,956 ) Property and equipment, net $ 21,873 $ 22,581 Accrued Warranty The following table shows changes in the Company's accrued warranties for the three and nine months ended September 30, 2018 and 2017 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Beginning accrued warranty balance $ 439 $ 253 $ 470 $ 219 Warranty expenses incurred (148 ) (126 ) (1,222 ) (675 ) Provisions 84 189 1,127 772 Ending accrued warranty balance $ 375 $ 316 $ 375 $ 316

Intangible Assets, net (Notes)

Intangible Assets, net (Notes)	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible assets, net	5. Intangible Assets, net Intangible assets as of September 30, 2018 and December 31, 2017 comprised the following (in thousands): September 30, 2018 December 31, 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Licensed intellectual property $ 4,750 $ (2,580 ) $ 2,170 $ 4,750 $ (2,126 ) $ 2,624 In July 2012, the Company entered into a development collaboration and license agreement with Advanced Liquid Logic, Inc., or ALL, which was acquired by Illumina, Inc. in July 2013. Under the terms of the agreement, the Company established a collaborative program to develop in-vitro diagnostic products incorporating ALL’s proprietary electro-wetting technology in conjunction with the Company’s electrochemical detection technology. During the nine months ended September 30, 2017 , the Company satisfied certain commercial milestones under this agreement requiring a payment of $500,000 recorded as an addition to licensed intellectual property. Intellectual property licenses have a weighted average remaining amortization period of 3.68 years as of September 30, 2018 . Amortization expense for these licenses was $156,000 and $151,000 for the three months ended September 30, 2018 and 2017 , respectively, and was $453,000 and $398,000 for the nine months ended September 30, 2018 and 2017 , respectively. Estimated future amortization expense for these licenses is as follows (in thousands): Fiscal Years Ending Future Amortization Expense Remaining in 2018 $ 139 2019 593 2020 593 2021 593 2022 252 Total $ 2,170

Loan Payable (Notes)

Loan Payable (Notes)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Loan payable	Long-term debt As of September 30, 2018 and December 31, 2017 , long-term debt consisted of the following (in thousands): September 30, 2018 December 31, 2017 Term Loans Term Loan A - $10.0 million at 6.9% interest $ 7,619 $ 7,619 Term Loan B - $10.0 million at 6.9% interest 7,619 7,619 Term Loan C - $15.0 million at 7.4% interest 12,000 12,000 Term Loan D - $0.7 million at 8.8% interest 663 — Final fee obligation 2,632 2,429 Unamortized issuance costs (1,803 ) (1,641 ) Total debt, net 28,730 28,026 Current portion of long-term debt — (7,927 ) Long-term debt $ 28,730 $ 20,099 Term Loans In January 2015, the Company entered into a Loan and Security Agreement, or the LSA, with Solar Capital Partners (as successor-in-interest to General Electric Capital Corporation), and certain other financial institutions party thereto, as lenders, or the Lenders, pursuant to which the Company obtained (a) up to $35,000,000 in a series of term loans and (b) a revolving loan in the maximum amount of $5,000,000 . The term loans accrue interest at a rate equal to ( a) the greater of 1.00% or the three year treasury rate in effect at the time of funding, plus (b) an applicable margin between 4.95% and 5.90% per annum. On September 28, 2018, the Company entered into a sixth amendment, or the Amendment, to its LSA. Pursuant to the Amendment, the Company and its Lenders agreed to extend the interest-only period in respect of amounts borrowed by the Company under the Agreement until January 1, 2020 . The parties also agreed to extend the final maturity date on which all of the Company’s loans, debts, obligations and other liabilities under the Agreement become due until January 1, 2021 , or the Final Maturity Date. In addition, the Amendment provides that outstanding principal and interest payments made by the Company to the Lenders between January 1, 2020 and the Final Maturity Date will be calculated on a 24-month amortization schedule, and that the Company will be required to make the final payment of all remaining outstanding principal and interest accrued thereon on the Final Maturity Date. Pursuant to the terms of the Amendment, the Lenders agreed to reallocate the Company’s borrowings under the Agreement among the Lenders and one Lender, or the Former Lender, was repaid in full their pro rata portion of the outstanding principal and interest borrowed by the Company under the Agreement. In connection with the Former Lender’s repayment, approximately $663,000 in additional principal was added to the Company’s borrowings pursuant to a new term loan made available under the Agreement, which amount was immediately used to pay the pro-rata portion of the final fee due to the Former Lender. As of September 30, 2018 , the Company had borrowed all $35,663,000 under the term loans as provided in the LSA, and the Company had not borrowed any of the $5,000,000 available under the revolving loan. The Company will be required to pay a $20 thousand annual management fee due on each anniversary of the closing date of the Amendment and a $2.6 million final payment fee due on the Final Maturity Date. The Amendment was accounted for as a debt modification with the issuance costs and fees of the term loans being amortized over the revised term of the LSA. Under the LSA, the Company is required to comply with certain affirmative and negative covenants, including, without limitation, delivering reports and notices relating to the Company’s financial condition and certain regulatory events and intellectual property matters, as well as limiting the creation of liens, the incurrence of indebtedness, and the making of certain investments, dividends, payments and acquisitions, other than as specifically permitted by the LSA. As of September 30, 2018 , the Company was in compliance with all covenants under the LSA. Revolving Loan Pursuant to the LSA, the Company may borrow up to $5,000,000 under a revolving loan facility. Borrowings under the revolving loan will accrue interest at a rate equal to (a) the greater of 1.25% per annum or a base rate as determined by a three-month LIBOR-based formula, plus (b) an applicable margin between 2.95% and 3.95% based on certain criteria as set forth in the LSA. All principal and interest outstanding under the revolving loan is due and payable on the Final Maturity Date. The Company is required to pay a commitment fee equal to 0.75% per annum of the amounts made available but unborrowed under the revolving loan. As of September 30, 2018 , the Company had not borrowed any amounts pursuant the revolving loan facility. Debt Issuance Costs As of September 30, 2018 and December 31, 2017 , the Company had $1,803,000 and $1,641,000 , respectively, of unamortized debt issuance discount, which is offset against borrowings in long-term and short-term debt. Amortization of debt issuance costs was $142,000 and $398,000 for the three months ended September 30, 2018 and 2017 , respectively, and was $725,000 and $891,000 for the nine months ended September 30, 2018 and 2017 , respectively. Amortization of debt issuance costs is included in interest expense in the Company's unaudited condensed consolidated statements of comprehensive loss for the periods presented. Letter of Credit In September 2012, the Company provided a $758,000 letter of credit issued by Banc of California to the landlord of its executive office facility in Carlsbad, California. This letter of credit was secured with $758,000 of restricted cash as of September 30, 2018 .

Leases (Notes)

Leases (Notes)	9 Months Ended
	Sep. 30, 2018
Leases [Abstract]
Leases	Leases The Company has operating and capital lease agreements for its office, manufacturing, warehousing and laboratory space and for office equipment. Rent and operating expenses charged under these arrangements was $485,000 and $399,000 for the three months ended September 30, 2018 and 2017 , respectively, and was $1,355,000 and $1,211,000 for the nine months ended September 30, 2018 and 2017 , respectively. Pursuant to the Company's lease agreements, a portion of the monthly rent has been deferred. The balance of deferred rent as of September 30, 2018 and December 31, 2017 was $3,373,000 and $3,652,000 , respectively. In July 2018, the Company entered into an amendment to the existing lease for its corporate headquarters, which extended the term of the lease by an additional four years through June 2025. Base rent adjusts periodically throughout the extended term of this lease with monthly lease payments ranging from $107,000 to $117,000 . The Company also received certain abatements to their rent during the three and nine months ended September 30, 2018. As of September 30, 2018 , the future minimum lease payments required over the next five years under the Company's lease arrangements are as follows (in thousands): Fiscal Years Ending Future Minimum Lease Payments Remaining in 2018 $ 227 2019 1,989 2020 1,997 2021 2,015 2022 2,077 Thereafter 4,023 Total $ 12,328

Fair Value of Financial Instrum

Fair Value of Financial Instruments (Notes)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair value of financial instruments	Fair Value of Financial Instruments The carrying amounts of financial instruments, such as cash equivalents, restricted cash, accounts receivable, and accounts payable approximate the related fair values due to the short-term maturities of these instruments. The Company uses a fair value hierarchy with three levels of inputs, of which the first two are considered observable and the last unobservable, to measure fair value: • Level 1 — Quoted prices in active markets for identical assets or liabilities. • Level 2 — Inputs, other than Level 1, that are observable, either directly or indirectly, such as 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 market data for substantially the full term of the assets or liabilities. • Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The following table presents the financial instruments measured at fair value on a recurring basis and the valuation approach applied to each class of financial instruments as of September 30, 2018 and December 31, 2017 (in thousands): September 30, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash equivalents Money market funds $ 9,986 $ — $ — $ 9,986 Marketable securities Corporate notes and bonds — 11,382 — 11,382 U.S. government and agency securities — 3,493 — 3,493 Commercial paper — 2,782 — 2,782 Total $ 9,986 $ 17,657 $ — $ 27,643 December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash equivalents Money market funds $ 6,362 $ — $ — $ 6,362 Corporate notes and bonds — 1,498 — 1,498 Marketable securities Corporate notes and bonds — 26,278 — 26,278 U.S. government and agency securities — 11,976 — 11,976 Commercial paper — 6,982 — 6,982 Total $ 6,362 $ 46,734 $ — $ 53,096 Level 2 marketable securities are priced using quoted market prices for similar instruments or nonbinding market prices that are corroborated by observable market data. The Company uses inputs such as actual trade data, benchmark yields, broker/dealer quotes, and other similar data, which are obtained from quoted market prices, independent pricing vendors, or other sources, to determine the ultimate fair value of these assets and liabilities. The Company uses such pricing data as the primary input to make its assessments and determinations as to the ultimate valuation of its investment portfolio and has not made, during the periods presented, any material adjustments to such inputs.

Marketable Securities (Notes)

Marketable Securities (Notes)	9 Months Ended
	Sep. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Marketable securities	Marketable Securities The following table summarizes the Company’s marketable securities as of September 30, 2018 and December 31, 2017 (in thousands): September 30, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate notes and bonds $ 11,386 $ — $ (4 ) $ 11,382 U.S. government and agency securities 3,494 — (1 ) 3,493 Commercial paper 2,782 — — 2,782 Total $ 17,662 $ — $ (5 ) $ 17,657 December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate notes and bonds $ 26,303 $ — $ (25 ) $ 26,278 U.S. government and agency securities 11,981 — (5 ) 11,976 Commercial paper 6,982 — — 6,982 Total $ 45,266 $ — $ (30 ) $ 45,236 All of the Company's marketable securities have a maturity of one year or less.

Income Taxes (Notes)

Income Taxes (Notes)	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company uses an estimated annual effective tax rate, which is based on expected annual income, statutory tax rates and tax planning opportunities available in the various jurisdictions in which the Company operates, to determine its quarterly provision for income taxes. Certain significant or unusual items are separately recognized in the quarter in which they occur and can be a source of variability in the effective tax rates from quarter to quarter. As of September 30, 2018 , the Company recorded a full valuation allowance against all of its net deferred tax assets due to the uncertainty surrounding the Company’s ability to utilize these assets in the future. Due to the Company's losses, it only records a tax provision or benefit related to uncertain tax positions and related interest and minimum tax payments or refunds. The Company recorded income tax expense (benefit) of $5,000 and $(9,000) for the three months ended September 30, 2018 and 2017 , and income tax expense of $59,000 and $68,000 for the nine months ended September 30, 2018 and 2017 , respectively. The Company continues to monitor guidance issued by the U.S. Treasury Department, the Internal Revenue Service, and other standard-setting bodies related to the Tax Cuts and Jobs Act, or the Jobs Act, enacted in 2017. Due to the timing of the enactment and the complexity involved in applying the provisions of the Jobs Act, the Company made reasonable estimates of the effects and recorded provisional amounts in the consolidated financial statements as of December 31, 2017. No adjustments were made to the provisional amounts recorded related to the Jobs Act during the nine months ended September 30, 2018 . The Company expects to complete the accounting for tax effects of the Jobs Act in fiscal year 2018. The Company is subject to taxation in the United States and in various state and foreign jurisdictions. The Company's federal and state returns since inception are subject to examination due to the carryover of net operating losses. As of September 30, 2018 , the Company’s tax years from 2011 through 2012 are subject to examination by the United Kingdom tax authorities related to legacy operations. The statute of limitations for the assessment and collection of income taxes related to other foreign tax returns varies by country. In the foreign countries where we have operations, these time periods generally range from three to five years after the year for which the tax return is due or the tax is assessed.

Organization and Basis of Pre_2

Organization and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation and Principles of Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles, or U.S. GAAP, and applicable regulations of the U.S. Securities and Exchange Commission, or the SEC, and should be read in conjunction with the audited financial statements included in the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the SEC on February 27, 2018. These unaudited condensed consolidated financial statements reflect all adjustments that are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. These adjustments are of a normal, recurring nature. Interim period operating results may not be indicative of the operating results for the full year or any future period. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. The Company has experienced net losses and negative cash flows from operating activities since its inception and had an accumulated deficit of $455,322,000 as of September 30, 2018 . The Company's ability to transition to profitable operations is dependent upon achieving a level of revenues adequate to support its cost structure through expanding its product offerings and consequently increasing its product revenues. As of September 30, 2018 , the Company had available cash, cash equivalents, and marketable securities of $42,662,000 and working capital of $48,137,000 available to fund future operations. The Company has prepared cash flow forecasts which indicate, based on the Company's current cash resources available and working capital, that the Company will have sufficient resources to fund its operations for at least one year after the date the financial statements are issued.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and the notes thereto. The Company’s significant estimates included in the preparation of the financial statements are related to accounts receivable, inventories, property and equipment, intangible assets, employee-related compensation accruals, warranty liabilities, tax valuation accounts and stock-based compensation. Actual results could differ from those estimates.
Segment Information	Segment Information The Company currently operates in one reportable business segment, which encompasses the development, manufacturing, sales and support of instruments and molecular tests based on its proprietary eSensor® detection technology. Substantially all of the Company’s operations and assets are in the United States.
Recent Accounting Pronouncements	Recent Accounting Pronouncements From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board, or the FASB, or other standard setting bodies that the Company adopts as of the specified effective date. In June 2018, the FASB issued Accounting Standards Update, or ASU 2018-07, Compensation - Stock Compensation (Topic 718) , which simplifies the accounting for non-employee share-based payment transactions. The new standard expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from non-employees. ASU 2018-07 is effective for fiscal years beginning after December 15, 2018 (including interim periods within that fiscal year), with early adoption permitted. The Company adopted the new standard in the second quarter of 2018 and determined that the application of the new standard did not have a material impact on the Company's unaudited condensed consolidated financial statements. In November 2016, the FASB issued ASU, 2016-18, Statement of Cash Flows (Topic 230) Restricted Cash , which requires amounts generally described as restricted cash and restricted cash equivalents to be included in the cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for fiscal years beginning after December 15, 2017 (including interim periods within those periods) using a retrospective transition method for each period presented, with early adoption permitted. The Company adopted the new standard in the first quarter of 2018 using the retrospective transition method resulting in an increase in the beginning and ending cash balance of $758,000 for each period presented. In February 2016, the FASB issued ASU 2016-02, Leases, which outlines a comprehensive lease accounting model and supersedes the current lease guidance. The new guidance requires lessees to recognize lease liabilities and corresponding right-of-use assets for all leases with lease terms of greater than 12 months. It also changes the definition of a lease and expands the disclosure requirements of lease arrangements. The new guidance must be adopted using the modified retrospective approach and will be effective for the Company starting in the first quarter of 2019, with early adoption permitted. The Company believes that adoption of this guidance will modify its analysis and disclosures of lease agreements because operating agreements are a significant portion of the Company's total lease commitments. The Company intends to adopt this guidance in the first quarter of 2019 and is in the process of determining the effects the adoption of this guidance will have on its unaudited condensed consolidated financial statements. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), an updated standard on revenue recognition. The new standard provides enhancements to the quality and consistency of how revenue is reported under the principle that revenue should be recognized in an amount that reflects the consideration to which the Company expects to be entitled in exchange for the transfer of promised goods or services. The Company adopted the new standard using the modified retrospective transition method. The cumulative effect of applying the new standard as of January 1, 2018 resulted in a net increase in opening retained earnings of $736,000 to capitalize certain costs to obtain sales contracts. The Company recognized $400,000 in expense related to the amortization of capitalized contract costs during the nine months ended September 30, 2018. Aside from this adjustment to beginning retained earnings and the related amortization of expense during the nine months ended September 30, 2018, the application of this standard did not have a material impact on the Company's unaudited condensed consolidated financial statements as of and for the nine months ended September 30, 2018.
Revenue from Contract with Customer	Revenue The Company recognizes revenue from operations through the sale of products and other services. Product revenue is comprised of the sale of diagnostic tests and instruments. Revenue is recognized when control of products and services is transferred to the customer in an amount that reflects the consideration that the Company expects to receive from the customer in exchange for those products and services. This process involves identifying the contract with the customer, determining the performance obligations in the contract, determining the contract price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when the performance obligations have been satisfied. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers a performance obligation satisfied once it has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The Company recognizes revenue for satisfied performance obligations only when it determines there are no uncertainties regarding payment terms or transfer of control. Revenue from product sales is recognized generally upon shipment to the end customer, which is when control of the product is deemed to be transferred. Invoicing typically occurs upon shipment and the term between invoicing and when payment is due is not significant. Revenue from instrument services is recognized as the services are rendered, typically evenly over the contract term. Revenue is recorded net of discounts and sales taxes collected on behalf of governmental authorities. Employee sales commissions are recorded as selling, general and administrative expenses when incurred or amortized over the estimated contract term when resulting from new contract acquisition efforts. The Company allocates contract price to each performance obligation in proportion to its stand-alone selling price. The stand-alone selling price is determined by the Company's best estimate of stand-alone selling price using average selling prices over a rolling 12-month period along with a specific assessment of any unique circumstances of the contract. For those products for which there is limited sales history, the Company makes price determination based on similar product sales data. The following table represents disaggregated revenue by source (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Revenue Source: ePlex product revenue $ 6,743 $ 2,311 $ 25,757 $ 4,385 XT-8 product revenue 8,970 9,241 25,399 31,928 Total product revenue 15,713 11,552 51,156 36,313 License and other revenue 82 51 225 184 Total revenue $ 15,795 $ 11,603 $ 51,381 $ 36,497
Cash, Cash Equivalents and Marketable Securities	Cash, Cash Equivalents and Marketable Securities Cash and cash equivalents consist of cash on deposit with banks, money market instruments and certificates of deposit with original maturities of three months or less at the date of purchase. Marketable securities consist of certificates of deposits that mature in greater than three months. Marketable securities are accounted for as "available-for-sale" with the carrying amounts reported in the balance sheets stated at cost, which approximates their fair market value, with unrealized gains and losses, if any, reported as a separate component of stockholders' equity and included in comprehensive loss.
Receivables	Receivables Accounts receivable consist of amounts due to the Company for sales to customers and are recorded net of an allowance for doubtful accounts. The allowance for doubtful accounts is determined based on an assessment of the collectability of specific customer accounts, the aging of accounts receivable, and a reserve for unknown items based upon the Company’s historical experience.
Product Warranties	Product Warranties The Company generally offers a one year warranty for its instruments sold to customers and typically up to a sixty day warranty for consumables. Factors that affect the Company’s warranty reserves include the number of units sold, historical and anticipated rates of warranty repairs, and the cost per repair. The Company periodically assesses the adequacy of its warranty reserve and adjusts the amount as appropriate.
Intangible Assets	Intangible Assets Intangible assets comprise licenses or sublicenses to technology covered by patents owned by third parties, and are amortized on a straight-line basis over the expected useful lives of these assets, which is generally ten years. Amortization of licenses typically begins upon the Company obtaining access to the licensed technology and is recorded in cost of revenues for licenses supporting commercialized products. The amortization of licenses to technology supporting products in development is recorded in research and development expenses.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company assesses the recoverability of long-lived assets, including intangible assets, by periodically evaluating the carrying value whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. If impairment is indicated, the Company writes down the carrying value of the asset to its estimated fair value. This fair value is primarily determined based on estimated discounted cash flows.
Inventories	Inventories Inventories are stated at the lower of cost (first-in, first-out) or net realizable value and include direct labor, materials, and manufacturing overhead. The Company periodically reviews inventory for evidence of slow-moving or obsolete parts, and writes inventory down to net realizable value, as needed. This write-down is based on management’s review of inventories on hand, compared to estimated future usage and sales, shelf-life assumptions, and assumptions about the likelihood of obsolescence. If actual market conditions are less favorable than those projected by the Company, additional inventory write-downs may be required. Inventory impairment charges establish a new cost basis for inventory and charges are not reversed subsequently to income, even if circumstances later suggest that increased carrying amounts are recoverable.
Property and Equipment, net	Property and Equipment, net Property, equipment and leasehold improvements are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets, which are identified below. Repair and maintenance costs are expensed as incurred. Machinery and laboratory equipment 3 - 5 years Instruments 4 - 5 years Office equipment 3 - 7 years Leasehold improvements over the shorter of the remaining life of the lease or the useful economic life of the asset
Income Taxes	Income Taxes Current income tax expense is the amount of income taxes expected to be payable for the current year. A deferred income tax liability or asset is established for the expected future tax consequences resulting from the differences in financial reporting and tax bases of assets and liabilities. A valuation allowance is provided if it is more likely than not that some or all of the deferred tax assets will not be realized. A full valuation allowance has been recorded against the Company’s net deferred tax assets due to the uncertainty surrounding the Company’s ability to utilize these assets in the future. The Company provides for uncertain tax positions when such tax positions do not meet the recognition thresholds or measurement standards prescribed by the authoritative guidance on income taxes. Amounts for uncertain tax positions are adjusted in periods when new information becomes available or when positions are effectively settled. The Company recognizes accrued interest related to uncertain tax positions as a component of income tax expense. A tax position that is more likely than not to be realized is measured at the largest amount of tax benefit that is greater than 50% likely of being realized upon settlement with the taxing authority that has full knowledge of all relevant information. Measurement of a tax position that meets the more likely than not threshold considers the amounts and probabilities of the outcomes that could be realized upon settlement using the facts, circumstances and information available at the reporting date.

Organization and Basis of Pre_3

Organization and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Disaggregation of Revenue	The following table represents disaggregated revenue by source (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Revenue Source: ePlex product revenue $ 6,743 $ 2,311 $ 25,757 $ 4,385 XT-8 product revenue 8,970 9,241 25,399 31,928 Total product revenue 15,713 11,552 51,156 36,313 License and other revenue 82 51 225 184 Total revenue $ 15,795 $ 11,603 $ 51,381 $ 36,497
Property, Plant and Equipment	Property, equipment and leasehold improvements are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets, which are identified below. Repair and maintenance costs are expensed as incurred. Machinery and laboratory equipment 3 - 5 years Instruments 4 - 5 years Office equipment 3 - 7 years Leasehold improvements over the shorter of the remaining life of the lease or the useful economic life of the asset Property and Equipment, Net September 30, 2018 December 31, 2017 Property and equipment — at cost: Machinery and laboratory equipment $ 15,296 $ 13,762 Instruments 14,778 13,347 Office equipment 2,146 1,948 Leasehold improvements 10,612 10,480 Total property and equipment — at cost 42,832 39,537 Less: accumulated depreciation (20,959 ) (16,956 ) Property and equipment, net $ 21,873 $ 22,581

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of share-based compensation, stock options, activity	The following table summarizes stock option activity during the nine months ended September 30, 2018 : Number of Shares Weighted Average Exercise Price Outstanding at December 31, 2017 2,490,465 $ 9.59 Granted — $ — Exercised (5,042 ) $ 4.33 Cancelled (40,153 ) $ 11.20 Outstanding at September 30, 2018 2,445,270 $ 9.58 Vested and expected to vest at September 30, 2018 2,443,432 $ 9.58 Exercisable at September 30, 2018 2,383,339 $ 9.49
Schedule of share-based compensation, restricted stock units, activity	The Company’s restricted stock unit activity for the nine months ended September 30, 2018 and 2017 was as follows: Restricted Stock Units Number of Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2017 2,073,440 $ 9.14 Granted 1,726,126 $ 4.51 Vested (750,310 ) $ 9.54 Cancelled (137,308 ) $ 8.83 Unvested at September 30, 2018 2,911,948 $ 6.30
Schedule of share-based compensation, market based stock units, activity	The Company’s market-based stock unit activity for the nine months ended September 30, 2018 was as follows: Market-Based Stock Units Number of Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2017 233,743 $ 10.88 Target units granted 320,000 $ 7.19 Unvested at September 30, 2018 553,743 $ 8.75
Schedule of share-based compensation, market based stock units, valuation assumptions	The fair value of these market-based stock units was estimated on the date of grant using the Monte Carlo Simulation Valuation Model, which estimates the potential outcome of achieving the market condition based on simulated future stock prices, with the following assumptions for the nine months ended September 30, 2018 : Nine Months Ended September 30, 2018 2017 Expected volatility 65 % 54 % Risk-free interest rate 2.40 % 1.50 % Expected dividend — % — % Weighted average fair value $ 7.19 $ 13.82
Schedule of employee service share-based compensation, allocation of recognized period costs	Stock-based compensation was recognized in the unaudited condensed consolidated statements of comprehensive loss as follows (in thousands): Three Months Ended Nine Months Ended 2018 2017 2018 2017 Cost of revenue $ 230 $ 124 $ 637 $ 398 Sales and marketing 719 703 2,059 2,061 Research and development 605 693 1,890 2,121 General and administrative 1,542 1,264 4,309 3,806 Total stock-based compensation expense $ 3,096 $ 2,784 $ 8,895 $ 8,386

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Computations of diluted net loss per share	The computations of diluted net loss per share for the three and nine month periods ended September 30, 2018 and 2017 did not include the effects of the following stock options and other equity awards which were outstanding as of the end of each period because the inclusion of these securities would have been anti-dilutive (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Options outstanding to purchase common stock 2,445 2,526 2,445 2,526 Other unvested equity awards 3,466 2,466 3,466 2,466 Total 5,911 4,992 5,911 4,992

Condensed Consolidated Financ_2

Condensed Consolidated Financial Statement Details (Tables)	9 Months Ended
	Sep. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Inventories	Inventory September 30, 2018 December 31, 2017 Raw materials $ 2,805 $ 4,534 Work-in-process 4,037 3,638 Finished goods 4,412 2,777 Total inventories $ 11,254 $ 10,949
Property and equipment, net	Property, equipment and leasehold improvements are recorded at cost and depreciated using the straight-line method over the estimated useful lives of the assets, which are identified below. Repair and maintenance costs are expensed as incurred. Machinery and laboratory equipment 3 - 5 years Instruments 4 - 5 years Office equipment 3 - 7 years Leasehold improvements over the shorter of the remaining life of the lease or the useful economic life of the asset Property and Equipment, Net September 30, 2018 December 31, 2017 Property and equipment — at cost: Machinery and laboratory equipment $ 15,296 $ 13,762 Instruments 14,778 13,347 Office equipment 2,146 1,948 Leasehold improvements 10,612 10,480 Total property and equipment — at cost 42,832 39,537 Less: accumulated depreciation (20,959 ) (16,956 ) Property and equipment, net $ 21,873 $ 22,581
Accrued warranty	Accrued Warranty The following table shows changes in the Company's accrued warranties for the three and nine months ended September 30, 2018 and 2017 (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Beginning accrued warranty balance $ 439 $ 253 $ 470 $ 219 Warranty expenses incurred (148 ) (126 ) (1,222 ) (675 ) Provisions 84 189 1,127 772 Ending accrued warranty balance $ 375 $ 316 $ 375 $ 316

Intangible Assets, net (Tables)

Intangible Assets, net (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of intangible assets	Intangible assets as of September 30, 2018 and December 31, 2017 comprised the following (in thousands): September 30, 2018 December 31, 2017 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Licensed intellectual property $ 4,750 $ (2,580 ) $ 2,170 $ 4,750 $ (2,126 ) $ 2,624
Summary of estimated future amortization expense	Estimated future amortization expense for these licenses is as follows (in thousands): Fiscal Years Ending Future Amortization Expense Remaining in 2018 $ 139 2019 593 2020 593 2021 593 2022 252 Total $ 2,170

Loan Payable (Tables)

Loan Payable (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Schedule of long-term debt instruments	As of September 30, 2018 and December 31, 2017 , long-term debt consisted of the following (in thousands): September 30, 2018 December 31, 2017 Term Loans Term Loan A - $10.0 million at 6.9% interest $ 7,619 $ 7,619 Term Loan B - $10.0 million at 6.9% interest 7,619 7,619 Term Loan C - $15.0 million at 7.4% interest 12,000 12,000 Term Loan D - $0.7 million at 8.8% interest 663 — Final fee obligation 2,632 2,429 Unamortized issuance costs (1,803 ) (1,641 ) Total debt, net 28,730 28,026 Current portion of long-term debt — (7,927 ) Long-term debt $ 28,730 $ 20,099

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2018
Leases [Abstract]
Schedule of future minimum lease payments	As of September 30, 2018 , the future minimum lease payments required over the next five years under the Company's lease arrangements are as follows (in thousands): Fiscal Years Ending Future Minimum Lease Payments Remaining in 2018 $ 227 2019 1,989 2020 1,997 2021 2,015 2022 2,077 Thereafter 4,023 Total $ 12,328

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Assets measured at fair value on a recurring basis	The following table presents the financial instruments measured at fair value on a recurring basis and the valuation approach applied to each class of financial instruments as of September 30, 2018 and December 31, 2017 (in thousands): September 30, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash equivalents Money market funds $ 9,986 $ — $ — $ 9,986 Marketable securities Corporate notes and bonds — 11,382 — 11,382 U.S. government and agency securities — 3,493 — 3,493 Commercial paper — 2,782 — 2,782 Total $ 9,986 $ 17,657 $ — $ 27,643 December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Cash equivalents Money market funds $ 6,362 $ — $ — $ 6,362 Corporate notes and bonds — 1,498 — 1,498 Marketable securities Corporate notes and bonds — 26,278 — 26,278 U.S. government and agency securities — 11,976 — 11,976 Commercial paper — 6,982 — 6,982 Total $ 6,362 $ 46,734 $ — $ 53,096

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Marketable securities, gross unrealized gains/losses	September 30, 2018 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate notes and bonds $ 11,386 $ — $ (4 ) $ 11,382 U.S. government and agency securities 3,494 — (1 ) 3,493 Commercial paper 2,782 — — 2,782 Total $ 17,662 $ — $ (5 ) $ 17,657 December 31, 2017 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate notes and bonds $ 26,303 $ — $ (25 ) $ 26,278 U.S. government and agency securities 11,981 — (5 ) 11,976 Commercial paper 6,982 — — 6,982 Total $ 45,266 $ — $ (30 ) $ 45,236

Organization and Basis of Pre_4

Organization and Basis of Presentation - Revenue disaggregation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue
Product revenue	$ 15,713	$ 11,552	$ 51,156	$ 36,313
License and other revenue	82	51	225	184
Total revenue	15,795	11,603	51,381	36,497
ePlex Revenue
Disaggregation of Revenue
Product revenue	6,743	2,311	25,757	4,385
XT-8 Revenue
Disaggregation of Revenue
Product revenue	$ 8,970	$ 9,241	$ 25,399	$ 31,928

Organization and Basis of Pre_5

Organization and Basis of Presentation - Property and equipment (Details)	9 Months Ended
	Sep. 30, 2018
Property and Equipment
Finite-Lived Intangible Asset, Useful Life	10 years
Machinery and laboratory equipment | Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	3 years
Machinery and laboratory equipment | Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	5 years
Instruments | Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	4 years
Instruments | Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	5 years
Office equipment | Minimum
Property and Equipment
Property, Plant, and Equipment, Useful Life	3 years
Office equipment | Maximum
Property and Equipment
Property, Plant, and Equipment, Useful Life	7 years
Leasehold improvements
Property and Equipment
Property, Plant and Equipment, Estimated Useful Lives	over the shorter of the remaining life of the lease or the useful economic life of the asset

Organization and Basis of Pre_6

Organization and Basis of Presentation - Additional information (Details Textual)	9 Months Ended
	Sep. 30, 2018USD ($)Segment	Dec. 31, 2017USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated deficit	$ (455,322,000)	$ (416,383,000)
Cash, cash equivalents, and marketable securities	42,662,000
Working Capital	$ 48,137,000
Sufficient capital to fund its operations	1 year
Number of Reportable Segments | Segment	1
Restricted cash	$ 758,000	$ 758,000
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	736,000
Capitalized Contract Cost, Amortization	$ 400,000
Instruments
Product Warranty Liability
Product warranty period	one year
Reagents
Product Warranty Liability
Product warranty period	sixty day

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock awards activity (Details) - 2010 Equity Incentive Plan - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, outstanding at December 31, 2017, shares	2,490,465
Options, granted, shares	0
Options, exercised, shares	(5,042)
Options, cancelled, shares	(40,153)
Options, outstanding at June 30, 2018, shares	2,445,270
Options, vested and expected to vest, shares	2,443,432
Options, exercisable, shares	2,383,339
Options, outstanding at December 31, 2017, weighted average exercise price	$ 9.58		$ 9.58	$ 9.59
Options, granted, weighted average exercise price	0
Options, exercised, weighted average exercise price	4.33
Options, cancelled, weighted average exercise price	11.20
Options, outstanding at June 30, 2018, weighted average exercise price	9.58
Options, vested and expected to vest, weighted average exercise price	9.58
Options, exercisable, weighted average exercise price	$ 9.49
Options, exercisable, weighted average remaining contractual term	4 years 4 months 17 days
Options, exercisable, intrinsic value			$ 1,729,000
Options, outstanding, weighted average remaining contractual term	4 years 5 months 5 days
Options, outstanding, intrinsic value			1,734,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award other than options, unvested at December 31, 2017, shares	2,073,440
Equity award other than options, granted, shares	1,726,126
Equity award other than options, vested, shares	(750,310)
Equity award other than options, cancelled, shares	(137,308)
Equity award other than options, unvested at June 30, 2018, shares	2,911,948
Equity award other than options, unvested, weighted average grant date fair value	$ 9.14
Equity award other than options, granted, weighted average grant date fair value	4.51
Equity award other than options, vested, weighted average grant date fair value	9.54
Equity award other than options, cancelled, weighted average grant date fair value	8.83
Equity award other than options, unvested, weighted average grant date fair value	$ 6.30
Equity award other than options, vested in period, fair value	$ 4,392,029	$ 4,181,000
Nonvested award, compensation cost not yet recognized			12,780,000
Nonvested award, compensation cost not yet recognized, weighted average period for recognition	2 years 6 months 29 days
Market-based share unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award other than options, unvested at December 31, 2017, shares	233,743
Equity award other than options, granted, shares	320,000
Equity award other than options, unvested at June 30, 2018, shares	553,743
Equity award other than options, unvested, weighted average grant date fair value	$ 10.88
Equity award other than options, granted, weighted average grant date fair value	7.19	$ 13.82
Equity award other than options, unvested, weighted average grant date fair value	$ 8.75
Nonvested award, compensation cost not yet recognized			$ 1,451,000
Nonvested award, compensation cost not yet recognized, weighted average period for recognition	1 year 6 months 11 days

Stock-Based Compensation - Valu

Stock-Based Compensation - Valuation assumptions (Details) - 2010 Equity Incentive Plan - Market-based share unit - $ / shares	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value assumptions, expected volatility rate	65.00%	54.00%
Fair value assumptions, risk free interest rate	2.40%	1.50%
Fair value assumptions, expected dividend rate	0.00%	0.00%
Equity award other than options, granted, weighted average grant date fair value	$ 7.19	$ 13.82

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense recognition (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation	$ 3,096,000	$ 2,784,000	$ 8,895,000	$ 8,386,000
Allocated share-based compensation expense, capitalized amount	0	0	0	0
Allocated share-based compensation expense, tax benefit	0	0	0	0
2010 Equity Incentive Plan | Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated share-based compensation expense	230,000	124,000	637,000	398,000
2010 Equity Incentive Plan | Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated share-based compensation expense	719,000	703,000	2,059,000	2,061,000
2010 Equity Incentive Plan | Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated share-based compensation expense	605,000	693,000	1,890,000	2,121,000
2010 Equity Incentive Plan | General and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated share-based compensation expense	$ 1,542,000	$ 1,264,000	$ 4,309,000	$ 3,806,000

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional information (Details) - shares	9 Months Ended
	Sep. 30, 2018	May 22, 2013
2010 Equity Incentive Plan | Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Award expiration period	10 years
2010 Equity Incentive Plan | Restricted Stock Units (RSUs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
2010 Equity Incentive Plan | Restricted Stock Units (RSUs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
2010 Equity Incentive Plan | Market-based share unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum MSU payout percentage	200.00%
Award vesting period	3 years
2013 Employee Stock Purchase Plan | Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized		650,000
Number of shares available for grant	1,059,213
Discount from market price, offering date	85.00%
Maximum number of shares per employee	1,500
Maximum employee subscription rate	0.00%
2013 Employee Stock Purchase Plan | Employee stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	6 months
2013 Employee Stock Purchase Plan | Employee stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Offering period	27 months
2013 Employee Stock Purchase Plan Amended and Restated | Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	1,750,000

Net Loss per Common Share - Bas

Net Loss per Common Share - Basic and diluted (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Computations of diluted net loss per share
Antidilutive securities excluded from calculation	5,911	4,992	5,911	4,992
Employee Stock Option
Computations of diluted net loss per share
Antidilutive securities excluded from calculation	2,445	2,526	2,445	2,526
Other unvested equity awards
Computations of diluted net loss per share
Antidilutive securities excluded from calculation	3,466	2,466	3,466	2,466

Condensed Consolidated Financ_3

Condensed Consolidated Financial Statement Details - Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Summary of inventory on hand
Raw materials	$ 2,805	$ 4,534
Work-in-process	4,037	3,638
Finished goods	4,412	2,777
Total	$ 11,254	$ 10,949

Condensed Consolidated Financ_4

Condensed Consolidated Financial Statement Details - Property and equipment, net (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property and Equipment
Property and equipment — at cost:	$ 42,832	$ 39,537
Less: accumulated depreciation	(20,959)	(16,956)
Property and equipment, net	21,873	22,581
Machinery and laboratory equipment
Property and Equipment
Property and equipment — at cost:	15,296	13,762
Instruments
Property and Equipment
Property and equipment — at cost:	14,778	13,347
Office equipment
Property and Equipment
Property and equipment — at cost:	2,146	1,948
Leasehold improvements
Property and Equipment
Property and equipment — at cost:	$ 10,612	$ 10,480

Condensed Consolidated Financ_5

Condensed Consolidated Financial Statement Details - Accrued warranty (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Product Warranties Disclosures [Abstract]
Beginning accrued warranty balance	$ 439	$ 253	$ 470	$ 219
Warranty expenses incurred	(148)	(126)	(1,222)	(675)
Provisions	84	189	1,127	772
Ending accrued warranty balance	$ 375	$ 316	$ 375	$ 316

Intangible Assets, net - Compon

Intangible Assets, net - Components of gross and net intangible asset balances (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Amortization of intangible assets	$ 156	$ 453
Finite-lived intangible assets
Net carrying amount	2,170	$ 2,170
Finite-lived intangible assets acquired			$ 500
Finite-lived intangible assets, remaining amortization period		3 years 8 months 5 days
Intellectual Property
Finite-lived intangible assets
Gross carrying amount	4,750	$ 4,750		$ 4,750
Accumulated amortization	(2,580)	(2,580)		(2,126)
Net carrying amount	$ 2,170	$ 2,170		$ 2,624

Intangible Assets, net - Future

Intangible Assets, net - Future amortization expense (Details) $ in Thousands	Sep. 30, 2018USD ($)
Summary of estimated future amortization expense
Remaining in 2018	$ 139
2,019	593
2,020	593
2,021	593
2,022	252
Net carrying amount	$ 2,170

Loan Payable - Term loans and l

Loan Payable - Term loans and line of credit (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Debt Instrument
Debt Instrument, Fee Amount	$ 20,000	$ 20,000
Unamortized debt issuance costs	(1,803,000)	(1,803,000)		$ (1,641,000)
Long-term debt, current maturities	0	0		(7,927,000)
Long-term debt, excluding current maturities	28,730,000	28,730,000		20,099,000
Amortization of deferred debt issuance costs		725,000	$ 891,000
Long-term debt, gross	663,000	663,000
Restricted cash	758,000	758,000		758,000
Letter of credit
Debt Instrument
Letters of credit outstanding, amount	758,000	$ 758,000
Revolving credit facility
Debt Instrument
Line of credit facility, interest rate description		(a) the greater of 1.25% per annum or a base rate as determined by a three-month LIBOR-based formula, plus (b) an applicable margin between 2.95% and 3.95%
Line of credit facility, unused capacity, commitment fee percentage		0.75%
Line of credit facility, maximum borrowing capacity	5,000,000	$ 5,000,000
Line of credit facility, fair value of amount outstanding	0	0		0
Term Loan A - $10.0 million at 6.9% interest
Debt Instrument
Long-term debt	$ 7,619,000	$ 7,619,000		7,619,000
Debt instrument, interest rate, stated percentage	6.90%	6.90%
Line of credit facility, maximum borrowing capacity	$ 10,000,000	$ 10,000,000		10,000,000
Term Loan B - $10.0 million at 6.9% interest
Debt Instrument
Long-term debt	$ 7,619,000	$ 7,619,000		7,619,000
Debt instrument, interest rate, stated percentage	6.90%	6.90%
Line of credit facility, maximum borrowing capacity	$ 10,000,000	$ 10,000,000		10,000,000
Term Loan C - $15.0 million at 7.4% interest
Debt Instrument
Long-term debt	$ 12,000,000	$ 12,000,000		12,000,000
Debt instrument, interest rate, stated percentage	7.40%	7.40%
Line of credit facility, maximum borrowing capacity	$ 15,000,000	$ 15,000,000		15,000,000
Term Loan D - $0.7 million at 8.8% interest
Debt Instrument
Long-term debt	663,000	663,000		0
Final fee obligation	2,632,000	2,632,000		2,429,000
Amortization of deferred debt issuance costs	142,000	$ 725,000
Debt instrument, interest only period end		Jan. 1, 2020
Long-term debt, gross	35,663,000	$ 35,663,000
Debt instrument, maturity date		Jan. 1, 2021
Debt instrument, interest rate terms		a) the greater of 1.00% or the three year treasury rate in effect at the time of funding, plus (b) an applicable margin between 4.95% and 5.90% per annum.
Line of credit facility, maximum borrowing capacity	35,000,000	$ 35,000,000		35,000,000
Total debt, net
Debt Instrument
Long-term debt	28,730,000	28,730,000		28,026,000
Long-term debt, current maturities	0	0		(7,927,000)
Long-term debt, excluding current maturities	28,730,000	28,730,000		$ 20,099,000
Long-term Debt [Member]
Debt Instrument
Debt Instrument, Fee Amount	$ 2,600,000	$ 2,600,000

Leases - Future minimum lease p

Leases - Future minimum lease payments (Details) $ in Thousands	Sep. 30, 2018USD ($)
Schedule of future minimum lease payments
Remaining in 2018	$ 227
2,019	1,989
2,020	1,997
2,021	2,015
2,022	2,077
Thereafter	4,023
Total future minimum payments	$ 12,328

Leases - Additional information

Leases - Additional information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Lessee, Lease, Description [Line Items]
Rent and operating expenses	$ 485,000	$ 399,000	$ 1,355,000	$ 1,211,000
Deferred rent	$ 3,373,000		$ 3,373,000		$ 3,652,000
Description of Lessee Leasing Arrangements, Operating Leases			107,000
Lease Agreements [Member]
Lessee, Lease, Description [Line Items]
Description of Lessee Leasing Arrangements, Operating Leases			117,000

Fair Value of Financial Instr_3

Fair Value of Financial Instruments - Fair value hierarchy (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair value, assets measured on a recurring basis
Marketable securities	$ 17,657	$ 45,236
Financial instruments, fair value	27,643	53,096
Level 1
Fair value, assets measured on a recurring basis
Financial instruments, fair value	9,986	6,362
Level 2
Fair value, assets measured on a recurring basis
Financial instruments, fair value	17,657	46,734
Level 3
Fair value, assets measured on a recurring basis
Financial instruments, fair value	0	0
Money market funds
Fair value, assets measured on a recurring basis
Cash equivalents	9,986	6,362
Money market funds | Level 1
Fair value, assets measured on a recurring basis
Cash equivalents	9,986	6,362
Money market funds | Level 2
Fair value, assets measured on a recurring basis
Cash equivalents	0	0
Money market funds | Level 3
Fair value, assets measured on a recurring basis
Cash equivalents	0	0
Corporate notes and bonds
Fair value, assets measured on a recurring basis
Cash equivalents		1,498
Marketable securities	11,382	26,278
Corporate notes and bonds | Level 1
Fair value, assets measured on a recurring basis
Cash equivalents		0
Marketable securities	0	0
Corporate notes and bonds | Level 2
Fair value, assets measured on a recurring basis
Cash equivalents		1,498
Marketable securities	11,382	26,278
Corporate notes and bonds | Level 3
Fair value, assets measured on a recurring basis
Cash equivalents		0
Marketable securities	0	0
U.S. government and agency securities
Fair value, assets measured on a recurring basis
Marketable securities	3,493	11,976
U.S. government and agency securities | Level 1
Fair value, assets measured on a recurring basis
Marketable securities	0	0
U.S. government and agency securities | Level 2
Fair value, assets measured on a recurring basis
Marketable securities	3,493	11,976
U.S. government and agency securities | Level 3
Fair value, assets measured on a recurring basis
Marketable securities	0	0
Commercial paper
Fair value, assets measured on a recurring basis
Marketable securities	2,782	6,982
Commercial paper | Level 1
Fair value, assets measured on a recurring basis
Marketable securities	0	0
Commercial paper | Level 2
Fair value, assets measured on a recurring basis
Marketable securities	2,782	6,982
Commercial paper | Level 3
Fair value, assets measured on a recurring basis
Marketable securities	$ 0	$ 0

Marketable Securities - Gross u

Marketable Securities - Gross unrealized gains/losses (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Marketable securities
Estimated fair value	$ 17,657	$ 45,236
Due in one year or less
Marketable securities
Amortized cost	(17,662)	(45,266)
Gross unrealized gains	0	0
Gross unrealized losses	(5)	(30)
Estimated fair value	17,657	45,236
Corporate notes and bonds
Marketable securities
Estimated fair value	11,382	26,278
Corporate notes and bonds | Due in one year or less
Marketable securities
Amortized cost	(11,386)	(26,303)
Gross unrealized gains	0	0
Gross unrealized losses	(4)	(25)
Estimated fair value	11,382	26,278
U.S. government and agency securities
Marketable securities
Estimated fair value	3,493	11,976
U.S. government and agency securities | Due in one year or less
Marketable securities
Amortized cost	(3,494)	(11,981)
Gross unrealized gains	0	0
Gross unrealized losses	(1)	(5)
Estimated fair value	3,493	11,976
Commercial paper
Marketable securities
Estimated fair value	2,782	6,982
Commercial paper | Due in one year or less
Marketable securities
Amortized cost	(2,782)	(6,982)
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	$ 2,782	$ 6,982

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ (5)	$ 9	$ (59)	$ (68)

Uncategorized Items - gnmk-2018

Label	Element	Value
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	$ 27,919,000