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Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2016	Oct. 28, 2016
Document and Entity Information
Entity Registrant Name	VERACYTE, INC.
Entity Central Index Key	0001384101
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		27,950,046
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q3

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 31,699	$ 39,084
Accounts receivable	6,312	3,503
Supplies inventory	3,416	3,767
Prepaid expenses and other current assets	1,405	1,442
Restricted cash	120	118
Total current assets	42,952	47,914
Property and equipment, net	10,435	10,314
Finite-lived intangible assets, net	14,400	15,200
Goodwill	1,057	1,057
Restricted cash	603	603
Other assets	203	159
Total assets	69,650	75,247
Current liabilities:
Accounts payable	3,081	5,085
Accrued liabilities	7,189	8,689
Deferred Genzyme co-promotion fee	0	948
Total current liabilities	10,270	14,722
Long-term debt	24,891	4,990
Deferred rent, net of current portion	4,484	4,283
Total liabilities	39,645	23,995
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized, no shares issued and outstanding as of September 30, 2016 and December 31, 2015	0	0
Common stock, $0.001 par value; 125,000,000 shares authorized, 27,940,161 and 27,685,291 shares issued and outstanding as of September 30, 2016 and December 31, 2015, respectively	28	28
Additional paid-in capital	205,658	199,950
Accumulated deficit	(175,681)	(148,726)
Total stockholders’ equity	30,005	51,252
Total liabilities and stockholders’ equity	$ 69,650	$ 75,247

Condensed Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	27,940,161	27,685,291
Common stock, shares outstanding	27,940,161	27,685,291

Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Revenue	$ 18,603	$ 12,335	$ 46,828	$ 35,461
Operating expenses:
Cost of revenue	6,367	5,618	18,947	15,322
Research and development	4,006	3,563	11,734	9,453
Selling and marketing	7,087	6,048	22,416	18,606
General and administrative	5,763	5,728	18,062	17,062
Intangible asset amortization	266	266	800	533
Total operating expenses	23,489	21,223	71,959	60,976
Loss from operations	(4,886)	(8,888)	(25,131)	(25,515)
Interest expense	(799)	(92)	(1,951)	(269)
Other income, net	48	35	127	93
Net loss	(5,637)	(8,945)	(26,955)	(25,691)
Comprehensive loss	$ (5,637)	$ (8,945)	$ (26,955)	$ (25,691)
Net loss per common share, basic and diluted (in usd per share)	$ (0.20)	$ (0.32)	$ (0.97)	$ (1.01)
Shares used to compute net loss per common share, basic and diluted	27,916,819	27,640,806	27,865,100	25,428,506

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Condensed Statements of Cash Flows - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2015
Operating activities
Net loss	$ (26,955)	$ (25,691)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,602	1,642
Bad debt expense	68	80
Loss on disposal of property and equipment	12	0
Genzyme co-promotion fee amortization	(948)	(1,423)
Stock-based compensation	4,745	4,186
Conversion of accrued interest to long-term debt	385	0
Amortization and write-off of debt discount and issuance costs	146	34
Interest on debt balloon payment and prepayment penalty	206	59
Changes in operating assets and liabilities:
Accounts receivable	(2,877)	(550)
Supplies inventory	351	(288)
Prepaid expenses and current other assets	37	(1,878)
Other assets	(44)	(53)
Accounts payable	(387)	(1,831)
Accrued liabilities and deferred rent	(1,091)	1,578
Net cash used in operating activities	(23,750)	(24,135)
Investing activities
Purchases of property and equipment	(3,760)	(1,975)
Change in restricted cash	(2)	(533)
Net cash used in investing activities	(3,762)	(2,508)
Financing activities
Proceeds from the issuance of long-term debt, net of debt issuance costs	24,452	0
Proceeds from the issuance of common stock in a private placement, net of costs	0	37,258
Payment of deferred stock offering costs	0	(197)
Payment of long-term debt	(5,000)	0
Payment of end-of-term debt obligation and prepayment penalty	(288)	0
Proceeds from the exercise of common stock options and employee stock purchases	963	684
Net cash provided by financing activities	20,127	37,745
Net (decrease) increase in cash and cash equivalents	(7,385)	11,102
Cash and cash equivalents at beginning of period	39,084	35,014
Cash and cash equivalents at end of period	31,699	46,116
Supplementary cash flow information of non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable and accrued liabilities	0	1,173
Unpaid deferred stock offering	$ 0	$ 71

Organization and Description of Business

9 Months Ended

Sep. 30, 2016

Accounting Policies [Abstract]

Organization and Description of Business

Veracyte, Inc. (“Veracyte” or the “Company”) was incorporated in the state of Delaware on August 15, 2006 as Calderome, Inc. Calderome operated as an incubator until early 2008. On March 4, 2008, the Company changed its name to Veracyte, Inc. Veracyte is a molecular diagnostics company that uses genomic technology to resolve diagnostic ambiguity. The Company targets diseases in which large numbers of patients undergo invasive and costly diagnostic procedures that could have been avoided with a more accurate diagnosis from a cytology sample. By improving diagnosis, the Company helps patients avoid such unnecessary invasive procedures and surgeries while reducing healthcare costs.

The Company’s first commercial solution, the Afirma^® Thyroid FNA Analysis, centers on the proprietary Afirma Gene Expression Classifier (“GEC”). The Afirma GEC helps physicians reduce the number of unnecessary surgeries by employing a proprietary 142-gene signature to determine whether thyroid nodules previously classified by cytopathology as indeterminate can be reclassified as benign. The Afirma GEC is offered directly or as part of a comprehensive solution that also includes cytopathology. Additionally, the Afirma Malignancy Classifiers were launched in May 2014. The Company currently markets and sells Afirma in the United States, in select foreign countries through a co-promotion agreement with Genzyme Corporation, a subsidiary of Sanofi, and through other distributors.

In April 2015, the Company entered the pulmonology diagnostics market with the Percepta^® Bronchial Genomic Classifier, a genomic test to resolve ambiguity in lung cancer diagnosis. In October 2016, the Company introduced a second product in pulmonology, the Envisia^™ Genomic Classifier, designed to help in the assessment of patients suspected to have idiopathic pulmonary fibrosis.

The Company’s operations are based in South San Francisco, California and Austin, Texas, and it operates in one segment in the United States.

Basis of Presentation

The Company’s financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The financial statements include the accounts of the Company and its former wholly-owned subsidiary, which was dissolved in June 2015. For periods prior to the subsidiary dissolution, all intercompany accounts and transactions were eliminated in consolidation. Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The condensed balance sheet as of September 30, 2016, the condensed statements of operations and comprehensive loss for the three and nine months ended September 30, 2016 and 2015, and the condensed statements of cash flows for the nine months ended September 30, 2016 and 2015 are unaudited, but include all adjustments, consisting only of normal recurring adjustments, which the Company considers necessary for a fair presentation of its financial position, operating results and cash flows for the periods presented. The condensed balance sheet at December 31, 2015 has been derived from audited financial statements. The results for the three and nine months ended September 30, 2016 are not necessarily indicative of the results expected for the full year or any other period. Certain amounts have been reclassified on the condensed balance sheet at December 31, 2015 to conform with the adoption of Accounting Standards Update (“ASU”) No. 2015-3, Simplifying the Presentation of Debt Issuance Costs.

The accompanying interim period condensed financial statements and related financial information included in this Quarterly Report on Form 10-Q should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015.

Use of Estimates

The preparation of the unaudited interim financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Significant items subject to such estimates include: revenue recognition; contractual allowances; the useful lives of property and equipment; the recoverability of long-lived assets; the estimation of the fair value of intangible assets; stock options; income tax uncertainties, including a valuation allowance for deferred tax assets; and contingencies. The Company bases these estimates on historical and anticipated results, trends and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates and assumptions.

Concentrations of Credit Risk and Other Risks and Uncertainties

The majority of the Company’s cash and cash equivalents are deposited with one major financial institution in the United States. Deposits in this institution may exceed the amount of insurance provided on such deposits. The Company has not experienced any losses on its deposits of cash and cash equivalents.

Several of the components of the Company’s sample collection kit and test reagents are obtained from single-source suppliers. If these single-source suppliers fail to satisfy the Company’s requirements on a timely basis, it could suffer delays in being able to deliver its diagnostic solutions, a possible loss of revenue, or incur higher costs, any of which could adversely affect its operating results.

The Company is also subject to credit risk from its accounts receivable related to its sales. The Company generally does not perform evaluations of customers’ financial condition and generally does not require collateral.

Through September 30, 2016, all of the Company’s revenue has been derived from the sale of Afirma. To date, Afirma has been delivered primarily to physicians in the United States. The Company’s third-party payers in excess of 10% of revenue and their related revenue as a percentage of total revenue were as follows:



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Medicare	23	%	28	%	27	%	27	%
UnitedHealthcare	11	%	11	%	12	%	13	%
	34	%	39	%	39	%	40	%

The Company’s significant third-party payers and their related accounts receivable balance as a percentage of total accounts receivable were as follows:



	September 30, 2016		December 31, 2015
Medicare	18	%	31	%
UnitedHealthcare	9	%	25	%
Aetna	7	%	23	%

No other third-party payer represented more than 10% of the Company’s accounts receivable balances as of those dates.

Restricted Cash

The Company had deposits of $120,000 and $118,000 as of September 30, 2016 and December 31, 2015, respectively, included in current assets. The deposit at September 30, 2016 was a pledge for corporate credit cards and the deposit at December 31, 2015 was restricted from withdrawal and held by a bank in the form of collateral for irrevocable standby letters of credit held as security for the lease of the Company’s former headquarters and laboratory facility in South San Francisco that expired March 31, 2016. The Company also had deposits of $603,000 included in long-term assets as of September 30, 2016 and December 31, 2015, restricted from withdrawal and held by a bank in the form of collateral for an irrevocable standby letter of credit held as security for the lease of the Company’s South San Francisco facility signed in April 2015.

Fair Value of Financial Instruments

The carrying amounts of certain financial instruments including cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities.

Revenue Recognition

The Company recognizes revenue in accordance with the provision of ASC 954-605, Health Care Entities — Revenue Recognition ("ASC 954"). The Company’s revenue is generated from the provision of diagnostic services. The service is completed upon the delivery of test results to the prescribing physician, at which time the Company bills for the service. The Company recognizes revenue related to billings for tests delivered on an accrual basis when amounts that will ultimately be realized can be reasonably estimated. The estimates of amounts that will ultimately be realized require significant judgment by management. Until a contract has been negotiated with a commercial payer or governmental program, the Company's tests may or may not be covered by these entities’ existing reimbursement policies. In addition, patients do not enter into direct agreements with the Company that commit them to pay any portion of the cost of the tests in the event that their insurance declines to reimburse the Company.

The Company may bill the patient directly for these amounts in the form of co-payments and co-insurance in accordance with their insurance carrier and health plans. The Company pursues reimbursement from such patients on a case-by-case basis. In the absence of contracted reimbursement or the ability to reasonably estimate the amount that will ultimately be realized for the Company’s services, revenue is recognized on a cash basis, i.e. upon the earlier of receipt of third-party payer notification of payment or when cash is received.

Revenue recognized on an accrual basis and cash basis for the three and nine months ended September 30, 2016 and 2015 was as follows (in thousands of dollars):



	Three Months Ended September 30,								Nine Months Ended September 30,
	2016		%		2015		%		2016		%		2015		%
Revenue recognized on an accrual basis	$	13,903	75	%	$	6,985	57	%	$	31,478	67	%	$	18,957	53	%
Revenue recognized on a cash basis	4,700		25	%	5,350		43	%	15,350		33	%	16,504		47	%
Total	$	18,603	100	%	$	12,335	100	%	$	46,828	100	%	$	35,461	100	%

Prior to July 1, 2016, the Company believes it did not have a consistent payment history to accrue a significant portion of its Afirma tests at the time of delivery and, as noted above, recognized revenue on a cash basis for such tests. The Company has been analyzing the amounts received for tests performed since commercialization and during the quarter ended September 30, 2016, concluded there was sufficient information to support a reasonable estimate of the amount of revenue to accrue upon test delivery for a number of payers that had been previously recognized on a cash basis. The Company considered factors such as coverage from payers, whether there is a reimbursement contract between the payer and the Company, the percentage of tests delivered for which payment is received, timeliness of payment, payment as a percentage of agreed upon rate, amount paid per test and any current developments or changes that could impact reimbursement to make an estimate of the amount to accrue upon test delivery in accordance with ASC 954. As a result, the Company recognized $3.5 million of incremental revenue during the quarter ended September 30, 2016 upon test delivery that previously would not have been recognized until notification of payment or cash was received. Tests performed prior to July 1, 2016 that did not meet the Company’s accrual criteria at the time of delivery will continue to be recognized as revenue on a cash basis. However, the Company expects the amount of revenue to be recognized on a cash basis for Afirma to decline in future periods since going forward relatively fewer tests will be performed for which a reasonable estimate of revenue to accrue will not have been made at the time of delivery.

Incremental accrued revenue as a result of additional payers meeting the Company's revenue recognition criteria was $3.5 million and $4.0 million for tests delivered in the three and nine months ended September 30, 2016, respectively, and $127,000 and $692,000 for tests delivered in the three and nine months ended September 30, 2015, respectively. The incremental accrued revenue decreased the loss from operations and net loss by $3.5 million and $4.0 million for the three and nine months ended September 30, 2016, respectively, and decreased the loss per common share by $0.13 and $0.14 for the three and nine months ended September 30, 2016, respectively.

Recent Accounting Pronouncements

In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2014-9, Revenue from Contracts with Customers, requiring an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The updated standard will replace most existing revenue recognition guidance in GAAP when it becomes effective and permits the use of either the retrospective or cumulative effect transition method. Adoption is permitted as early as the first quarter of 2017 and is required by the first quarter of 2018. The Company has not yet selected a transition method and is currently evaluating the potential effect of the updated standard on its financial statements.

In August 2014, FASB issued ASU No. 2014-15, Presentation of Financial Statements Going Concern - Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments require management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. Specifically, the amendments: (1) provide a definition of the term substantial doubt; (2) require an evaluation every reporting period including interim periods; (3) provide principles for considering the mitigating effect of management’s plans; (4) require certain disclosures when substantial doubt is alleviated as a result of consideration of management’s plans; (5) require an express statement and other disclosures when substantial doubt is not alleviated; and (6) require an assessment for a period of one year after the date that the financial statements are issued (or available to be issued). ASU 2014-15 will be effective for annual periods ending after December 15, 2016 and interim periods within annual periods beginning after December 15, 2016 with early adoption permitted. ASU 2014-15 will be effective for the Company beginning with its annual report for 2016 and interim periods thereafter. The Company does not anticipate that the adoption of this ASU will have a significant impact on its financial statements.

In April 2015, the FASB issued ASU No. 2015-3, Simplifying the Presentation of Debt Issuance Costs, to require debt issuance costs to be presented as an offset against debt outstanding. The update does not change current guidance on the recognition and measurement of debt issuance costs. The ASU is effective for interim and annual periods beginning after December 15, 2015. Adoption of the ASU is retrospective to each prior period presented. The Company has adopted this ASU and the retrospective adjustment of the prior period presentation was not material.

In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes. The ASU requires that deferred tax assets and liabilities be classified as noncurrent in the statement of financial position, thereby simplifying the guidance that required an entity to separate deferred assets and liabilities into current and noncurrent amounts, and was effective for the Company beginning in the first quarter of 2016. The Company early-adopted this ASU as of December 31, 2015 and the impact of adoption on its statement of financial position was not material.

In February 2016, the FASB issued ASU No. 2016-2, Leases. This ASU is aimed at making leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. The ASU will be effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the potential effect of the updated standard on its financial statements.

In March 2016, the FASB issued ASU 2016-9, Compensation - Stock Compensation, related to the tax effects of share-based awards. The ASU requires that all the tax effects of share-based awards be recorded through the income statement, thereby simplifying the current guidance that requires excess tax benefits and certain excess tax deficiencies to be recorded in equity. The ASU will be effective for interim and annual periods beginning after December 15, 2016. The Company does not anticipate that the adoption of this ASU will have a significant impact on its financial statements.

Net Loss Per Common Share

9 Months Ended

Sep. 30, 2016

Earnings Per Share [Abstract]

Net Loss Per Common Share

Basic net loss per common share is calculated by dividing net loss attributable to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration of common stock equivalents. Diluted net loss per common share is computed by dividing net loss attributable to common stockholders by the weighted-average number of common share equivalents outstanding for the period determined using the treasury stock method. The following outstanding common stock equivalents have been excluded from diluted net loss per common share because their inclusion would be anti-dilutive:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Shares of common stock subject to outstanding options	5,312,081	4,241,020	5,031,926	4,041,644
Employee stock purchase plan	29,435	8,730	34,262	2,942
Total common stock equivalents	5,341,516	4,249,750	5,066,188	4,044,586

Accrued Liabilities

9 Months Ended

Sep. 30, 2016

Payables and Accruals [Abstract]

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands of dollars):



	September 30, 2016		December 31, 2015
Accrued compensation expenses	$	4,970	$	4,212
Accrued Genzyme co-promotion fees	—		2,089
Accrued other	2,219		2,388
Total accrued liabilities	$	7,189	$	8,689

Fair Value Measurements

9 Months Ended

Sep. 30, 2016

Fair Value Disclosures [Abstract]

Fair Value Measurements

The Company recognizes its financial assets and liabilities at fair value. The carrying amounts of certain financial instruments of the Company, including cash and cash equivalents, prepaid expenses and other current assets, accounts payable and accrued liabilities, approximate fair value due to their relatively short maturities. The carrying value of the Company’s debt approximates its fair value because the interest rate approximates market rates that the Company could obtain for debt with similar terms. The estimated fair value of the Company’s debt is estimated using the net present value of the payments, discounted at an interest rate that is consistent with market interest rates, which is a Level II input. The accounting guidance for fair value provides a framework for measuring fair value, clarifies the definition of fair value, and expands disclosures regarding fair value measurements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance establishes a three-tiered hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows:


•	Level I: Inputs which include quoted prices in active markets for identical assets and liabilities.


•	Level II: Inputs other than Level I 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 III: 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 fair value of the Company’s financial assets, which consist only of money market funds, was $29.4 million and $37.5 million as of September 30, 2016 and December 31, 2015, respectively, and are Level I assets as described above.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Commitments and Contingencies

9 Months Ended

Sep. 30, 2016

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Operating Leases

The Company leases its headquarters and laboratory facilities in South San Francisco, California under a non-cancelable lease agreement for approximately 59,000 square feet. The lease began in June 2015 and ends in March 2026 and contains extension of lease term and expansion options. The Company had deposits of $603,000 included in long-term assets as of September 30, 2016 and December 31, 2015, restricted from withdrawal and held by a bank in the form of collateral for an irrevocable standby letter of credit held as security for the lease of the South San Francisco facility.

The Company also leases laboratory and office space in Austin, Texas under a lease that expires on July 31, 2018. The Company provided a cash security deposit of $75,000 upon entering into this lease, which is included in other assets in the Company’s condensed balance sheets as of September 30, 2016 and December 31, 2015.

Future minimum lease payments under non-cancelable operating leases as of September 30, 2016 are as follows (in thousands of dollars):



Year Ending December 31,
2016	$	523
2017	2,143
2018	2,102
2019	2,026
2020	2,082
Thereafter	11,956
Total minimum lease payments	$	20,832

The Company recognizes rent expense on a straight-line basis over the non-cancelable lease period. Rent expense was $457,000 and $687,000 for the three months ended September 30, 2016 and 2015, respectively, and $1.5 million and $1.3 million for the nine months ended September 30, 2016 and 2015, respectively.

Supplies Purchase Commitments

The Company had non-cancelable purchase commitments with five suppliers to purchase a minimum quantity of supplies for approximately $1.5 million at September 30, 2016.

Contingencies

From time to time, the Company may be involved in legal proceedings arising in the ordinary course of business. The Company believes there is no litigation pending that could have, individually or in the aggregate, a material adverse effect on the Company’s financial position, results of operations or cash flows.

Debt

9 Months Ended

Sep. 30, 2016

Debt Disclosure [Abstract]

Debt

Credit Agreement

In March 2016, the Company entered into a credit agreement (the “Credit Agreement”) with Visium Healthcare Partners, LP (“Visium”). Under the Credit Agreement, two term loans are available to the Company with an aggregate principal amount of up to $40.0 million. The Company drew down the initial $25.0 million term loan (the “Initial Term Loan”) on March 30, 2016, of which $5.0 million was used to pay the outstanding balance of the Company’s existing long-term debt, which was cancelled at that date. On or prior to June 30, 2017, the Company may request the second term loan of up to $15.0 million (the “Second Term Loan” and together with the Initial Term Loan, the “Term Loans”). The Term Loans mature on March 31, 2022.

The Term Loans bear interest at a fixed rate of 12.0% per annum, payable quarterly at the end of each March, June, September and December. No principal payments will be due during an interest-only period, commencing on the funding date for the Initial Term Loan (the “Initial Borrowing Date”) and continuing through and including March 31, 2020. The Company is obligated to repay the outstanding principal amounts under the Term Loans in eight equal installments during the final two years under the Credit Agreement. For any quarterly interest payment through and including the 16th interest payment date after the Initial Borrowing Date, so long as no event of default has occurred and is then continuing, the Company may elect to pay interest in cash on the outstanding principal amounts of the Term Loans at a fixed rate of 9.0%, with the remaining 3.0% of the 12.0% interest paid-in-kind by adding such paid-in-kind interest to the outstanding principal amounts of the Term Loans. The Company elected to pay interest in-kind for the quarter ended September 30, 2016 and has recorded $385,000 of paid-in-kind interest through September 30, 2016.

The Company may prepay the outstanding principal amount under the Term Loans subject to a minimum of $5.0 million of principal amount or a whole multiple of $1.0 million in excess thereof plus accrued and unpaid interest and a prepayment premium. The prepayment premium will be assessed on the principal amount repaid and will equal (i) 24.0% less the aggregate amount of all interest payments in cash, if the prepayment is made on or prior to March 31, 2018, (ii) 4.0%, if the prepayment is made after March 31, 2018 and on or prior to March 31, 2019, (iii) 2.0%, if the prepayment is made after March 31, 2019 and on or prior to March 31, 2020, and (iv) 1.0%, if the prepayment is made after March 31, 2020 and on or prior to March 31, 2021. After March 31, 2021 there is no prepayment premium.

The Company’s obligations under the Credit Agreement are secured by a security interest in substantially all of its assets. The Credit Agreement contains customary representations, warranties and events of default, as well as affirmative and negative covenants. The negative covenants include, among other provisions, covenants that limit or restrict the Company’s ability to incur liens, make investments, incur indebtedness, merge with or acquire other entities, dispose of assets, make dividends or other distributions to holders of its equity interests, engage in any material new line of business or enter into certain transactions with affiliates, in each case subject to certain exceptions. To the extent the Company forms or acquires certain subsidiaries domiciled in the United States, those subsidiaries are required to be guarantors of the Company’s obligations under the Credit Agreement. As of September 30, 2016, the Company was in compliance with the loan covenants.

Concurrent with entering into the Credit Agreement, the Company entered into an agreement with Visium pursuant to which, for a period of one year following the Initial Borrowing Date, Visium has the right to participate in certain future equity financings of the Company in an amount of up to $5.0 million with no preferential terms.

As of September 30, 2016, the net debt obligation for borrowings made under the Credit Agreement was as follows (in thousands of dollars):



	September 30, 2016
Debt principal	$	25,385
Unamortized deferred debt issuance costs	(494		)
Net debt obligation	$	24,891

Future principal payments under the Credit Agreement are as follows (in thousands of dollars):



Year Ending December 31,
2020	$	9,519
Thereafter	15,866
Total	$	25,385

Loan and Security Agreement

In June 2013, the Company entered into a loan and security agreement as subsequently amended (“2013 Loan Agreement”) with a financial institution that provided for borrowings of up to $10.0 million in aggregate. Borrowings under the 2013 Loan Agreement totaled $5.0 million, which was outstanding at January 1, 2015 and into 2016 until such amount was repaid upon the Company entering into the Credit Agreement discussed above.

Interest Expense

Interest expense was as follows (in thousands of dollars):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Nominal interest	$	772	$	64	$	1,600	$	189
Amortization and write-off of debt discount and debt issuance costs	27		7		145		20
Prepayment penalty	—		—		50		—
End-of-term payment interest	—		21		156		60
Total	$	799	$	92	$	1,951	$	269

Stockholders' Equity

9 Months Ended

Sep. 30, 2016

Equity [Abstract]

Stockholders' Equity

Stockholders’ Equity

Common Stock

The Company had reserved shares of common stock for issuance as follows:



	September 30, 2016	December 31, 2015
Options issued and outstanding	5,287,887	4,179,521
Options available for grant under stock option plans	950,486	1,058,359
Common stock available for the Employee Stock Purchase Plan	609,053	750,000
Total	6,847,426	5,987,880

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Stock Incentive Plans

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock Incentive Plans

The following table summarizes activity under the Company’s stock option plans (aggregate intrinsic value in thousands of dollars):



	Shares Available for Grant		Stock Options Outstanding		Weighted Average Exercise Price	Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Balance—December 31, 2015	1,058,359		4,179,521		$8.03	7.50	$6,511
Additional options authorized	1,107,411		—
Granted	(1,440,350	)	1,440,350		6.15
Canceled	225,066		(218,061	)	10.42
Exercised	—		(113,923	)	2.50
Balance—September 30, 2016	950,486		5,287,887		$7.54	7.63	$8,640
Options vested and exercisable—September 30, 2016			2,568,269		$7.15	6.34	$6,206
Options vested and expected to vest—September 30, 2016			5,059,400		$7.54	7.56	$8,421

The aggregate intrinsic value was calculated as the difference between the exercise price of the options to purchase common stock and the fair market value of the Company’s common stock, which was $7.61 per share as of September 30, 2016.

The weighted average fair value of options to purchase common stock granted was $3.29 and $5.23 for the nine months ended September 30, 2016 and 2015, respectively.

The intrinsic value of stock options exercised was $386,000 and $1.6 million for the nine months ended September 30, 2016 and 2015, respectively.

Stock-based Compensation

The following table summarizes stock-based compensation expense related to stock options and the Company's employee stock purchase plan (“ESPP”) for the three and nine months ended September 30, 2016 and 2015 (in thousands of dollars):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Cost of revenue	$	31	$	32	$	94	$	64
Research and development	342		296		982		891
Selling and marketing	396		353		1,199		943
General and administrative	803		793		2,470		2,288
Total stock-based compensation expense	$	1,572	$	1,474	$	4,745	$	4,186

As of September 30, 2016, the Company had $10.5 million of unrecognized compensation expense related to unvested stock options, which is expected to be recognized over an estimated weighted-average period of 2.55 years.

The estimated grant-date fair value of employee stock options was calculated using the Black-Scholes option-pricing model, based on the following assumptions:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Weighted-average volatility	52.68 – 52.90%	52.56 – 53.76%	52.68 – 56.36%	52.56 – 68.82%
Weighted-average expected term (years)	6.08	6.08	5.50 – 6.23	5.50 – 6.08
Risk-free interest rate	1.16 – 1.37%	1.57 – 1.92%	1.16 – 1.77%	1.55 – 2.03%
Expected dividend yield	—	—	—	—

There were no stock options granted to non-employees during the nine months ended September 30, 2016 and 2015.

The estimated grant date fair value of shares granted under the Company's ESPP was calculated using the Black-Scholes option-pricing model, based on the following assumptions:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Weighted-average volatility	46.38 – 62.85%	53.57 – 58.10%	46.38 – 75.72%	53.57 – 58.10%
Weighted-average expected term (years)	0.50 – 1.00	0.50 – 1.00	0.50 – 1.00	0.50 – 1.00
Risk-free interest rate	0.40 – 0.50%	0.17 – 0.33%	0.40 – 0.50%	0.17 – 0.33%
Expected dividend yield	—	—	—	—

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Genzyme Co-promotion Agreement	9 Months Ended
Genzyme Co-promotion Agreement	Sep. 30, 2016
Genzyme Co-promotion Agreement
Genzyme Co-promotion Agreement	Genzyme Co-Promotion Agreement In January 2012, the Company and Genzyme Corporation (“Genzyme”) executed a co-promotion agreement for the co-exclusive rights and license to promote and market the Company’s Afirma thyroid diagnostic solution in the United States and in 40 named countries. In exchange, the Company received a $10.0 million upfront co-promotion fee from Genzyme in February 2012. Under the terms of the agreement, Genzyme receives a percentage of U.S. cash receipts that the Company has received related to Afirma as co-promotion fees. The percentage was 50% in 2012, 40% from January 2013 through February 2014, and 32% beginning in February 2014. In November 2014, the Company signed an Amended and Restated U.S. Co-Promotion Agreement (“Amended Agreement”) with Genzyme. Under the Amended Agreement, the co-promotion fees Genzyme receives as a percentage of U.S. cash receipts were reduced from 32% to 15% beginning January 1, 2015. Through August 11, 2014, the Company amortized the $10.0 million upfront co-promotion fee straight-line over a four-year period, which was management’s best estimate of the life of the agreement, in part because after that period either party could have terminated the agreement without penalty. Effective August 12, 2014, the Company extended the amortization period from January 2016 to June 2016, the modified earliest period either party could terminate the agreement without penalty. The Company accounted for the change in accounting estimate prospectively. The agreement was terminable by either party with six months prior notice, however, under the Amended Agreement, neither party could terminate the agreement for convenience prior to June 30, 2016. The agreement with Genzyme was to expire in 2027. On March 9, 2016, the Company gave Genzyme notice of termination of the Amended Agreement effective September 9, 2016 and the amortization of the upfront co-promotion fee was further extended to that date. The extension of the amortization period has no impact on our 2016 financial statements on an annual basis. In February 2015, the Company entered into an Ex-U.S. Co-promotion Agreement with Genzyme for the promotion of the Afirma GEC test with exclusivity in five countries outside the United States initially and in other countries agreed to from time to time. The agreement commenced on January 1, 2015 and continues until December 31, 2019, with extension of the agreement possible upon agreement of the parties. Country-specific terms have been established under this agreement for Brazil and Singapore and a right of first negotiation has been established for Canada, the Netherlands and Italy. The Company pays Genzyme 25% of net revenue from the sale of the Afirma GEC test in Brazil and Singapore over a five-year period commencing January 1, 2015. These payments have been immaterial for all periods presented. Beginning in the fourth year of the agreement, if the Company terminates the agreement for convenience, the Company may be required to pay a termination fee contingent on the number of GEC billable results generated during the 12 months immediately prior to the notice of termination. The Company incurred $1.8 million and $1.8 million in co-promotion expense, excluding the amortization of the upfront co-promotion fee, for the three months ended September 30, 2016 and 2015, respectively, and $6.1 million and $5.2 million in co-promotion expense for the nine months ended September 30, 2016 and 2015, respectively, which is included in selling and marketing expenses in the condensed statements of operations and comprehensive loss. The Company had no outstanding obligations to Genzyme as of September 30, 2016, compared to $2.1 million as of December 31, 2015 which was included in accrued liabilities on the Company’s condensed balance sheet. The Company amortized $227,000 and $474,000 of the $10.0 million upfront co-promotion fee in the three months ended September 30, 2016 and 2015, respectively, and $948,000 and $1.4 million in the nine months ended September 30, 2016 and 2015, respectively, which is reflected as a reduction to selling and marketing expenses in the condensed statements of operations and comprehensive loss.

Thyroid Cytopathology Partners	9 Months Ended
Thyroid Cytopathology Partners	Sep. 30, 2016
Thyroid Cytopathology Partners
Thyroid Cytopathology Partners	Thyroid Cytopathology Partners In 2010, the Company entered into an arrangement with Pathology Resource Consultants, P.A. (“PRC”) to set up and manage a specialized pathology practice to provide testing services to the Company. There is no direct monetary compensation from the Company to PRC as a result of this arrangement. The Company’s service agreement is with the specialized pathology practice, Thyroid Cytopathology Partners, (“TCP”), and was effective through December 31, 2015, and thereafter automatically renews every year unless either party provides notice of intent not to renew at least 12 months prior to the end of the then-current term. Under the service agreement, the Company pays TCP based on a fixed price per test schedule, which is reviewed periodically for changes in market pricing. Subsequent to December 2012, an amendment to the service agreement allows TCP to sublease a portion of the Company’s facility in Austin, Texas. The Company does not have an ownership interest in or provide any form of financial or other support to TCP. The Company has concluded that TCP represents a variable interest entity and that the Company is not the primary beneficiary as it does not have the ability to direct the activities that most significantly impact TCP’s economic performance. Therefore, the Company does not consolidate TCP. All amounts paid to TCP under the service agreement are expensed as incurred and included in cost of revenue in the condensed statements of operations and comprehensive loss. The Company incurred $1.3 million and $1.2 million for the three months ended September 30, 2016 and 2015, respectively, and $3.8 million and $3.5 million for the nine months ended September 30, 2016 and 2015, respectively, in cytopathology testing and evaluation services expenses with TCP. The Company’s outstanding obligations to TCP for cytopathology testing services were $870,000 and $820,000 as of September 30, 2016 and December 31, 2015, respectively, and are included in accounts payable on the Company’s condensed balance sheets. TCP reimburses the Company for a proportionate share of the Company’s rent and related operating expenses for the leased facility. TCP’s portion of rent and related operating expense for the subleased space at the Austin, Texas facility was $24,000 and $23,000 for the three months ended September 30, 2016 and 2015, respectively, and $70,000 and $67,000 for the nine months ended September 30, 2016 and 2015, respectively, and is included in other income, net in the Company’s condensed statements of operations and comprehensive loss.

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company did not record a provision or benefit for income taxes during the three and nine months ended September 30, 2016 and 2015. The Company continues to maintain a full valuation allowance against its net deferred tax assets. As of September 30, 2016, the Company had unrecognized tax benefits of $2.1 million, none of which would currently affect the Company’s effective tax rate if recognized due to the Company’s net deferred tax assets being fully offset by a valuation allowance. The Company does not anticipate that the amount of unrecognized tax benefits relating to tax positions existing at September 30, 2016 will significantly increase or decrease within the next 12 months. There was no interest expense or penalties related to unrecognized tax benefits recorded through September 30, 2016. A number of years may elapse before an uncertain tax position is audited and finally resolved. While it is often difficult to predict the final outcome or the timing of resolution of any particular uncertain tax position, the Company believes that its reserves for income taxes reflect the most likely outcome. The Company adjusts these reserves, as well as the related interest, in light of changing facts and circumstances. Settlement of any particular position could require the use of cash.

Subsequent Event Subsequent Event	9 Months Ended
Subsequent Event Subsequent Event	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On November 1, 2016, the Company entered into an underwriting agreement relating to a public offering of 5 million shares of its common stock at a public offering price of $6.00 per share. The underwriters exercised their option to purchase up to 750,000 additional shares of its common stock at the public offering price, less underwriting discounts and commissions. Gross proceeds to the Company would be approximately $34.3 million upon closing. The closing is subject to customary closing conditions. The Company intends to use the net proceeds from the public offering for working capital and other general corporate purposes. The Company may also use a portion of the net proceeds from the offering to acquire or invest in complementary businesses, technologies or other assets, although it has no present commitments or agreements to do so.

Organization and Description of Business (Policies)	9 Months Ended
Organization and Description of Business (Policies)	Sep. 30, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company’s financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The financial statements include the accounts of the Company and its former wholly-owned subsidiary, which was dissolved in June 2015. For periods prior to the subsidiary dissolution, all intercompany accounts and transactions were eliminated in consolidation. Certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The condensed balance sheet as of September 30, 2016, the condensed statements of operations and comprehensive loss for the three and nine months ended September 30, 2016 and 2015, and the condensed statements of cash flows for the nine months ended September 30, 2016 and 2015 are unaudited, but include all adjustments, consisting only of normal recurring adjustments, which the Company considers necessary for a fair presentation of its financial position, operating results and cash flows for the periods presented. The condensed balance sheet at December 31, 2015 has been derived from audited financial statements. The results for the three and nine months ended September 30, 2016 are not necessarily indicative of the results expected for the full year or any other period. Certain amounts have been reclassified on the condensed balance sheet at December 31, 2015 to conform with the adoption of Accounting Standards Update (“ASU”) No. 2015-3, Simplifying the Presentation of Debt Issuance Costs. The accompanying interim period condensed financial statements and related financial information included in this Quarterly Report on Form 10-Q should be read in conjunction with the audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2015.
Use of Estimates	Use of Estimates The preparation of the unaudited interim financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Significant items subject to such estimates include: revenue recognition; contractual allowances; the useful lives of property and equipment; the recoverability of long-lived assets; the estimation of the fair value of intangible assets; stock options; income tax uncertainties, including a valuation allowance for deferred tax assets; and contingencies. The Company bases these estimates on historical and anticipated results, trends and various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates and assumptions.
Concentrations of Credit Risk and Other Risks and Uncertainties	Concentrations of Credit Risk and Other Risks and Uncertainties The majority of the Company’s cash and cash equivalents are deposited with one major financial institution in the United States. Deposits in this institution may exceed the amount of insurance provided on such deposits. The Company has not experienced any losses on its deposits of cash and cash equivalents. Several of the components of the Company’s sample collection kit and test reagents are obtained from single-source suppliers. If these single-source suppliers fail to satisfy the Company’s requirements on a timely basis, it could suffer delays in being able to deliver its diagnostic solutions, a possible loss of revenue, or incur higher costs, any of which could adversely affect its operating results. The Company is also subject to credit risk from its accounts receivable related to its sales. The Company generally does not perform evaluations of customers’ financial condition and generally does not require collateral.
Restricted Cash	Restricted Cash The Company had deposits of $120,000 and $118,000 as of September 30, 2016 and December 31, 2015, respectively, included in current assets. The deposit at September 30, 2016 was a pledge for corporate credit cards and the deposit at December 31, 2015 was restricted from withdrawal and held by a bank in the form of collateral for irrevocable standby letters of credit held as security for the lease of the Company’s former headquarters and laboratory facility in South San Francisco that expired March 31, 2016. The Company also had deposits of $603,000 included in long-term assets as of September 30, 2016 and December 31, 2015, restricted from withdrawal and held by a bank in the form of collateral for an irrevocable standby letter of credit held as security for the lease of the Company’s South San Francisco facility signed in April 2015.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts of certain financial instruments including cash and cash equivalents, accounts receivable, prepaid expenses and other current assets, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities.
Revenue Recognition	Revenue Recognition The Company recognizes revenue in accordance with the provision of ASC 954-605, Health Care Entities — Revenue Recognition ("ASC 954").
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2014-9, Revenue from Contracts with Customers, requiring an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The updated standard will replace most existing revenue recognition guidance in GAAP when it becomes effective and permits the use of either the retrospective or cumulative effect transition method. Adoption is permitted as early as the first quarter of 2017 and is required by the first quarter of 2018. The Company has not yet selected a transition method and is currently evaluating the potential effect of the updated standard on its financial statements. In August 2014, FASB issued ASU No. 2014-15, Presentation of Financial Statements Going Concern - Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments require management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. Specifically, the amendments: (1) provide a definition of the term substantial doubt; (2) require an evaluation every reporting period including interim periods; (3) provide principles for considering the mitigating effect of management’s plans; (4) require certain disclosures when substantial doubt is alleviated as a result of consideration of management’s plans; (5) require an express statement and other disclosures when substantial doubt is not alleviated; and (6) require an assessment for a period of one year after the date that the financial statements are issued (or available to be issued). ASU 2014-15 will be effective for annual periods ending after December 15, 2016 and interim periods within annual periods beginning after December 15, 2016 with early adoption permitted. ASU 2014-15 will be effective for the Company beginning with its annual report for 2016 and interim periods thereafter. The Company does not anticipate that the adoption of this ASU will have a significant impact on its financial statements. In April 2015, the FASB issued ASU No. 2015-3, Simplifying the Presentation of Debt Issuance Costs, to require debt issuance costs to be presented as an offset against debt outstanding. The update does not change current guidance on the recognition and measurement of debt issuance costs. The ASU is effective for interim and annual periods beginning after December 15, 2015. Adoption of the ASU is retrospective to each prior period presented. The Company has adopted this ASU and the retrospective adjustment of the prior period presentation was not material. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes. The ASU requires that deferred tax assets and liabilities be classified as noncurrent in the statement of financial position, thereby simplifying the guidance that required an entity to separate deferred assets and liabilities into current and noncurrent amounts, and was effective for the Company beginning in the first quarter of 2016. The Company early-adopted this ASU as of December 31, 2015 and the impact of adoption on its statement of financial position was not material. In February 2016, the FASB issued ASU No. 2016-2, Leases. This ASU is aimed at making leasing activities more transparent and comparable, and requires substantially all leases be recognized by lessees on their balance sheet as a right-of-use asset and corresponding lease liability, including leases currently accounted for as operating leases. The ASU will be effective for interim and annual periods beginning after December 15, 2018. Early adoption is permitted. The Company is currently evaluating the potential effect of the updated standard on its financial statements. In March 2016, the FASB issued ASU 2016-9, Compensation - Stock Compensation, related to the tax effects of share-based awards. The ASU requires that all the tax effects of share-based awards be recorded through the income statement, thereby simplifying the current guidance that requires excess tax benefits and certain excess tax deficiencies to be recorded in equity. The ASU will be effective for interim and annual periods beginning after December 15, 2016. The Company does not anticipate that the adoption of this ASU will have a significant impact on its financial statements.

Organization and Description of Business (Tables)

9 Months Ended

Sep. 30, 2016

Revenue Recognition

Schedule of Revenue recognized when cash is received and on an accrual basis

Revenue recognized on an accrual basis and cash basis for the three and nine months ended September 30, 2016 and 2015 was as follows (in thousands of dollars):



	Three Months Ended September 30,								Nine Months Ended September 30,
	2016		%		2015		%		2016		%		2015		%
Revenue recognized on an accrual basis	$	13,903	75	%	$	6,985	57	%	$	31,478	67	%	$	18,957	53	%
Revenue recognized on a cash basis	4,700		25	%	5,350		43	%	15,350		33	%	16,504		47	%
Total	$	18,603	100	%	$	12,335	100	%	$	46,828	100	%	$	35,461	100	%

Revenue concentration risk | Revenue

Concentration Risk

Schedule of the Company's third-party payers as a percentage of total

The Company’s third-party payers in excess of 10% of revenue and their related revenue as a percentage of total revenue were as follows:



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Medicare	23	%	28	%	27	%	27	%
UnitedHealthcare	11	%	11	%	12	%	13	%
	34	%	39	%	39	%	40	%

Gross receivables concentration risk | Accounts receivable

Concentration Risk

Schedule of the Company's third-party payers as a percentage of total

The Company’s significant third-party payers and their related accounts receivable balance as a percentage of total accounts receivable were as follows:



	September 30, 2016		December 31, 2015
Medicare	18	%	31	%
UnitedHealthcare	9	%	25	%
Aetna	7	%	23	%

Net Loss Per Common Share (Tables)

9 Months Ended

Sep. 30, 2016

Earnings Per Share [Abstract]

Schedule of outstanding shares of common stock equivalents that have been excluded from diluted net loss per common share

The following outstanding common stock equivalents have been excluded from diluted net loss per common share because their inclusion would be anti-dilutive:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Shares of common stock subject to outstanding options	5,312,081	4,241,020	5,031,926	4,041,644
Employee stock purchase plan	29,435	8,730	34,262	2,942
Total common stock equivalents	5,341,516	4,249,750	5,066,188	4,044,586

Accrued Liabilities (Tables)

9 Months Ended

Sep. 30, 2016

Payables and Accruals [Abstract]

Schedule of accrued liabilities

Accrued liabilities consisted of the following (in thousands of dollars):



	September 30, 2016		December 31, 2015
Accrued compensation expenses	$	4,970	$	4,212
Accrued Genzyme co-promotion fees	—		2,089
Accrued other	2,219		2,388
Total accrued liabilities	$	7,189	$	8,689

Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2016

Commitments and Contingencies Disclosure [Abstract]

Schedule of future minimum lease payments under non-cancelable operating leases

Future minimum lease payments under non-cancelable operating leases as of September 30, 2016 are as follows (in thousands of dollars):



Year Ending December 31,
2016	$	523
2017	2,143
2018	2,102
2019	2,026
2020	2,082
Thereafter	11,956
Total minimum lease payments	$	20,832

Debt (Tables)

9 Months Ended

Sep. 30, 2016

Debt Disclosure [Abstract]

Schedule of net debt obligation

As of September 30, 2016, the net debt obligation for borrowings made under the Credit Agreement was as follows (in thousands of dollars):



	September 30, 2016
Debt principal	$	25,385
Unamortized deferred debt issuance costs	(494		)
Net debt obligation	$	24,891

Schedule of future principal payments under the Credit agreement

Future principal payments under the Credit Agreement are as follows (in thousands of dollars):



Year Ending December 31,
2020	$	9,519
Thereafter	15,866
Total	$	25,385

Schedule of interest expense on debt

Interest expense was as follows (in thousands of dollars):



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Nominal interest	$	772	$	64	$	1,600	$	189
Amortization and write-off of debt discount and debt issuance costs	27		7		145		20
Prepayment penalty	—		—		50		—
End-of-term payment interest	—		21		156		60
Total	$	799	$	92	$	1,951	$	269

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2016

Equity [Abstract]

Schedule of reserved shares of common stock for issuance

The Company had reserved shares of common stock for issuance as follows:



	September 30, 2016	December 31, 2015
Options issued and outstanding	5,287,887	4,179,521
Options available for grant under stock option plans	950,486	1,058,359
Common stock available for the Employee Stock Purchase Plan	609,053	750,000
Total	6,847,426	5,987,880

Stock Incentive Plans (Tables)

9 Months Ended

Sep. 30, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of activity under the Company's stock option plans

The following table summarizes activity under the Company’s stock option plans (aggregate intrinsic value in thousands of dollars):



	Shares Available for Grant		Stock Options Outstanding		Weighted Average Exercise Price	Weighted Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
Balance—December 31, 2015	1,058,359		4,179,521		$8.03	7.50	$6,511
Additional options authorized	1,107,411		—
Granted	(1,440,350	)	1,440,350		6.15
Canceled	225,066		(218,061	)	10.42
Exercised	—		(113,923	)	2.50
Balance—September 30, 2016	950,486		5,287,887		$7.54	7.63	$8,640
Options vested and exercisable—September 30, 2016			2,568,269		$7.15	6.34	$6,206
Options vested and expected to vest—September 30, 2016			5,059,400		$7.54	7.56	$8,421

Summary of stock-based compensation expense



	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Cost of revenue	$	31	$	32	$	94	$	64
Research and development	342		296		982		891
Selling and marketing	396		353		1,199		943
General and administrative	803		793		2,470		2,288
Total stock-based compensation expense	$	1,572	$	1,474	$	4,745	$	4,186

Schedule of assumptions used to calculate estimated grant date fair value of stock options using the Black-Scholes option-pricing valuation model

The estimated grant-date fair value of employee stock options was calculated using the Black-Scholes option-pricing model, based on the following assumptions:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Weighted-average volatility	52.68 – 52.90%	52.56 – 53.76%	52.68 – 56.36%	52.56 – 68.82%
Weighted-average expected term (years)	6.08	6.08	5.50 – 6.23	5.50 – 6.08
Risk-free interest rate	1.16 – 1.37%	1.57 – 1.92%	1.16 – 1.77%	1.55 – 2.03%
Expected dividend yield	—	—	—	—

Schedule of grant date fair value of the ESPP shares was calculated using Black Scholes option

The estimated grant date fair value of shares granted under the Company's ESPP was calculated using the Black-Scholes option-pricing model, based on the following assumptions:



	Three Months Ended September 30,		Nine Months Ended September 30,
	2016	2015	2016	2015
Weighted-average volatility	46.38 – 62.85%	53.57 – 58.10%	46.38 – 75.72%	53.57 – 58.10%
Weighted-average expected term (years)	0.50 – 1.00	0.50 – 1.00	0.50 – 1.00	0.50 – 1.00
Risk-free interest rate	0.40 – 0.50%	0.17 – 0.33%	0.40 – 0.50%	0.17 – 0.33%
Expected dividend yield	—	—	—	—

Organization and Description of Business - Operating Segments (Details)	9 Months Ended
	Sep. 30, 2016 segment
Accounting Policies [Abstract]
Number of operating segments	1

Organization and Description of Business - Credit Risk (Details) - item	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Concentrations of Credit Risk and Other Risks and Uncertainties
Number of major financial institutions with which the company's cash and cash equivalents are deposited	1		1
Revenue \| Revenue concentration risk
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)	34.00%	39.00%	39.00%	40.00%
Revenue \| Revenue concentration risk \| Medicare
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)	23.00%	28.00%	27.00%	27.00%
Revenue \| Revenue concentration risk \| UnitedHealthcare
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)	11.00%	11.00%	12.00%	13.00%
Accounts receivable \| Gross receivables concentration risk \| Medicare
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)			18.00%		31.00%
Accounts receivable \| Gross receivables concentration risk \| UnitedHealthcare
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)			9.00%		25.00%
Accounts receivable \| Gross receivables concentration risk \| Aetna
Concentrations of Credit Risk and Other Risks and Uncertainties
Concentrations of credit risk (as a percent)			7.00%		23.00%

Organization and Description of Business - Restricted Cash and Allowance for Doubtful Accounts (Details) - USD ($)	Sep. 30, 2016	Dec. 31, 2015
Restricted Cash
Cash reserved to cover liabilities associated with Merger	$ 120,000	$ 118,000
Long term deposit consisting of letter of credit serving as security for lease	603,000	603,000
Headquarters and laboratory facility, South San Francisco, Lease expiring 2016
Restricted Cash
Cash reserved to cover liabilities associated with Merger	120,000	118,000
Headquarters and laboratory facilities, South San Francisco, Lease signed April 2015
Restricted Cash
Long term deposit consisting of letter of credit serving as security for lease	$ 603,000	$ 603,000

Organization and Description of Business - Revenue Recongition (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue Recognition
Revenue recognized when cash is received	$ 13,903	$ 6,985	$ 31,478	$ 18,957
Revenue recognized on accrual basis, percentage	75.00%	57.00%	67.00%	53.00%
Revenue recognized on an accrual basis	$ 4,700	$ 5,350	$ 15,350	$ 16,504
Revenue recognized received in cash, percentage	25.00%	43.00%	33.00%	47.00%
Total	$ 18,603	$ 12,335	$ 46,828	$ 35,461
Revenue, percent	100.00%	100.00%	100.00%	100.00%
Net loss per common share, basic and diluted (in usd per share)	$ (0.20)	$ (0.32)	$ (0.97)	$ (1.01)
Accrued Income Receivable
Revenue Recognition
Total	$ 3,500	$ 127	$ 4,000	$ 692
Net loss per common share, basic and diluted (in usd per share)	$ 0.13		$ 0.14

Net Loss Per Common Share (Details) - shares	3 Months Ended		9 Months Ended
Net Loss Per Common Share (Details) - shares	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Outstanding shares of common stock equivalents that have been excluded from diluted net loss per common share
Total common stock equivalents (in shares)	5,341,516	4,249,750	5,066,188	4,044,586
Shares of common stock subject to outstanding options
Outstanding shares of common stock equivalents that have been excluded from diluted net loss per common share
Total common stock equivalents (in shares)	5,312,081	4,241,020	5,031,926	4,041,644
Employee stock purchase plan
Outstanding shares of common stock equivalents that have been excluded from diluted net loss per common share
Total common stock equivalents (in shares)	29,435	8,730	34,262	2,942

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued compensation expenses	$ 4,970	$ 4,212
Accrued Genzyme co-promotion fees	0	2,089
Accrued other	2,219	2,388
Total accrued liabilities	$ 7,189	$ 8,689

Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Recurring \| Level I \| Money market funds
Fair value measurements
Financial Assets	$ 29.4	$ 37.5

Commitments and Contingencies (Details) ft² in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) supplier	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) ft² supplier	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Operating Leases
Long term deposit consisting of letter of credit serving as security for lease	$ 603		$ 603		$ 603
Future minimum lease payments under non-cancelable operating leases
2016	523		523
2017	2,143		2,143
2018	2,102		2,102
2019	2,026		2,026
2020	2,082		2,082
Thereafter	11,956		11,956
Total minimum lease payments	20,832		20,832
Facilities rent expense	$ 457	$ 687	$ 1,500	$ 1,300
Supplies Purchase Commitments
Number of suppliers \| supplier	5		5
Non-cancelable purchase commitment	$ 1,500		$ 1,500
Headquarters and laboratory facilities, South San Francisco, Lease signed April 2015
Operating Leases
Amount of space leased \| ft²			59
Security deposit	603		$ 603		603
Long term deposit consisting of letter of credit serving as security for lease	603		603		603
Laboratory facilities, Austin, Texas \| Other assets
Operating Leases
Security deposit	$ 75		$ 75		$ 75

Debt (Details)		1 Months Ended			3 Months Ended		9 Months Ended
Debt (Details)	Mar. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2014	Jun. 30, 2013 USD ($)	Sep. 30, 2016 USD ($) installment loan	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) installment loan	Sep. 30, 2015 USD ($)
Debt
Repayment of long-term debt							$ 5,000,000	$ 0
Paid-in-kind interest							385,000	0
Interest Expense, Debt [Abstract]
End-of-term payment interest							$ 206,000	59,000
Line of Credit \| Visium
Debt
Number of term loans \| loan					2		2
Maximum borrowing capacity					$ 40,000,000.0		$ 40,000,000.0
Interest rate (as a percent)					12.00%		12.00%
Number of installments \| installment					8		8
Term of debt with equal quarterly installments							2 years
Rate for which Company may elect to pay interest in cash (as a percent)					0.090		0.090
Remaining percentage for which interest is paid-in-kind					0.030		0.030
Paid-in-kind interest					$ 385,000
Prepayment allowed		$ 5,000,000
Whole multiple in excess of minimum prepayment		$ 1,000,000
Prepayment premium for prepayment made on or prior to March 31, 2018 (as a percent)		0.240
Prepayment premium for prepayment made after March 31, 2018 and on or prior to March 31, 2019 (as a percent)		0.040
Prepayment premium for prepayment made after March 31, 2019 and on or prior to March 31, 2020 (as a percent)		0.020
Prepayment premium for prepayment made after March 31, 2020 and on or prior to March 31, 2021 (as a percent)		0.010
Period for which lender has rights to participate in equity financings		1 year
Debt principal					25,385,000		$ 25,385,000
Unamortized deferred debt issuance costs					(494,000)		(494,000)
Net debt obligation					24,891,000		24,891,000
Future principal payments
2020					9,519,000		9,519,000
Thereafter					15,866,000		15,866,000
Total					25,385,000		25,385,000
Line of Credit \| Visium \| Maximum
Debt
Maximum amount allowed to participate in future equity financings					5,000,000.0		5,000,000.0
Line of Credit \| Visium \| Initial Term Loan
Debt
Drawn down initial term loan	$ 25,000,000
Repayment of long-term debt	$ 5,000,000
Line of Credit \| Visium \| Second Term Loan
Debt
Maximum borrowing capacity					15,000,000.0		15,000,000.0
Term Loans
Debt
Maximum borrowing capacity				$ 10,000,000.0
Prepayment premium for prepayment made after March 31, 2021 (as a percent)			0
Future principal payments
Amount drawn down				$ 5,000,000
Interest Expense, Debt [Abstract]
Nominal interest					772,000	$ 64,000	1,600,000	189,000
Amortization and write-off of debt discount and debt issuance costs					27,000	7,000	145,000	20,000
Prepayment penalty					0	0	50,000	0
End-of-term payment interest					0	21,000	156,000	60,000
Total					$ 799,000	$ 92,000	$ 1,951,000	$ 269,000

Stockholders' Equity (Details) - shares	Sep. 30, 2016	Dec. 31, 2015
Common Stock
Options issued and outstanding (in shares)	5,287,887	4,179,521
Shares available for issuance	950,486	1,058,359
Total number of shares reserved for issuance	6,847,426	5,987,880
Shares of common stock subject to outstanding options
Common Stock
Shares available for issuance	950,486	1,058,359
ESPP
Common Stock
Shares available for issuance	609,053	750,000

Stock Incentive Plans - Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Shares Available for Grant
Balance at the beginning of the period (in shares)	1,058,359
Additional options authorized (in shares)	1,107,411
Granted (in shares)	(1,440,350)
Canceled (in shares)	225,066
Balance at the end of the period (in shares)	950,486	1,058,359
Stock Options Outstanding
Balance at beginning of the period (in shares)	4,179,521
Granted (in shares)	1,440,350
Canceled (in shares)	(218,061)
Exercised (in shares)	(113,923)
Balance at the end of the period (in shares)	5,287,887	4,179,521
Options vested and exercisable at the end of the period (in shares)	2,568,269
Options vested and expected to vest at the end of the period (in shares)	5,059,400
Weighted Average Exercise Price
Balance at beginning of the period (in dollars per share)	$ 8.03
Granted (in dollars per share)	6.15
Canceled (in dollars per share)	10.42
Exercised (in dollars per share)	2.50
Balance at the end of the period (in dollars per share)	7.54	$ 8.03
Options vested and exercisable at the end of the period (in dollars per share)	7.15
Options vested and expected to vest at the end of the period (in dollars per share)	$ 7.54
Weighted Average Remaining Contractual Life
Balance (in years)	7 years 7 months 17 days	7 years 6 months
Options vested and exercisable at the end of the period (in years)	6 years 4 months 2 days
Options vested and expected to vest at the end of the period (in years)	7 years 6 months 22 days
Aggregate Intrinsic Value
Balance at the beginning of the period (in dollars)	$ 6,511
Balance at the end of the period (in dollars)	8,640	$ 6,511
Options vested and exercisable at the end of the period (in dollars)	6,206
Options vested and expected to vest at the end of the period (in dollars)	$ 8,421

Stock Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share Price	$ 7.61
Weighted average fair value of options to purchase common stock granted (in dollars per share)	$ 3.29	$ 5.23
Intrinsic value of stock options exercised (in dollars)	$ 386	$ 1,600

Stock Incentive Plans - Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Stock-based compensation
Granted (in shares)			1,440,350
Stock-based Compensation
Stock-based compensation
Share-based compensation expense (in dollars)	$ 1,572	$ 1,474	$ 4,745	$ 4,186
Unrecognized compensation expense (in dollars)	10,500		$ 10,500
Period over which unrecognized compensation expense expected to be recognized			2 years 6 months 18 days
Stock-based Compensation \| Cost of revenue
Stock-based compensation
Share-based compensation expense (in dollars)	31	32	$ 94	64
Stock-based Compensation \| Research and development
Stock-based compensation
Share-based compensation expense (in dollars)	342	296	982	891
Stock-based Compensation \| Selling and marketing
Stock-based compensation
Share-based compensation expense (in dollars)	396	353	1,199	943
Stock-based Compensation \| General and administrative
Stock-based compensation
Share-based compensation expense (in dollars)	$ 803	$ 793	$ 2,470	$ 2,288
Stock-based Compensation, employees
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average volatility, low end of range (as a percent)	52.68%	52.56%	52.68%	52.56%
Weighted-average volatility, high end of range (as a percent)	52.90%	53.76%	56.36%	68.82%
Risk free interest rate, maximum	1.37%	1.92%	1.77%	2.03%
Risk free interest rate, minimum	1.16%	1.57%	1.16%	1.55%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Stock-based Compensation, employees \| Minimum
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average expected term	6 years 29 days	6 years 29 days	5 years 6 months	5 years 6 months
Stock-based Compensation, employees \| Maximum
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average expected term	6 years 29 days	6 years 29 days	6 years 2 months 23 days	6 years 29 days
ESPP
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average volatility, low end of range (as a percent)	46.38%	46.38%	53.57%	53.57%
Weighted-average volatility, high end of range (as a percent)	62.85%	75.72%	58.10%	58.10%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
ESPP \| Minimum
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average expected term	6 months	6 months	6 months	6 months
Risk free interest rate	0.40%	0.40%	0.17%	0.17%
ESPP \| Maximum
Assumptions used to calculate estimated fair value of stock options using the Black-Scholes option-pricing valuation model
Weighted-average expected term	1 year	1 year	1 year	1 year
Risk free interest rate	0.50%	0.50%	0.33%	0.33%

Genzyme Co-promotion Agreement (Details) $ in Thousands		1 Months Ended	3 Months Ended		9 Months Ended		10 Months Ended	12 Months Ended		14 Months Ended	28 Months Ended	29 Months Ended	31 Months Ended
Genzyme Co-promotion Agreement (Details) $ in Thousands	Jan. 01, 2015	Feb. 29, 2012 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2014	Dec. 31, 2015 USD ($)	Dec. 31, 2012	Feb. 27, 2014	Jun. 30, 2016	Aug. 11, 2014 USD ($)	Aug. 11, 2014	Feb. 28, 2015 country	Jan. 31, 2012 country
Genzyme Co-promotion Agreement
Genzyme co-promotion fee amortization					$ 948	$ 1,423
Co-promotion agreement \| Genzyme
Genzyme Co-promotion Agreement
Genzyme co-promotion fee amortization			$ 227	$ 474	948	$ 1,400
Co-promotion agreement \| Genzyme \| Accrued liabilities
Genzyme Co-promotion Agreement
Co-promotion expenses					0			$ 2,100
Afirma thyroid diagnostic solution co-promotion agreement \| Genzyme
Genzyme Co-promotion Agreement
Number of countries outside United States for exclusive promotion under the agreement \| country															40
Co-promotion fee received from Genzyme		$ 10,000										$ 10,000
Co-promotion fees as a percentage of cash receipts							32.00%		50.00%	40.00%	32.00%
Co-promotion fees as a percentage of cash receipts for remaining periods						15.00%
Straight-line amortization period of co-promotion fee													4 years
Ex-U.S. Co-Promotion Agreement \| Genzyme
Genzyme Co-promotion Agreement
Number of countries outside United States for exclusive promotion under the agreement \| country														5
Co-promotion fee paid as a percentage of net revenue	25.00%
Period of agreement	5 years
Selling and marketing \| Co-promotion agreement \| Genzyme
Genzyme Co-promotion Agreement
Co-promotion expenses			$ 1,800	$ 1,800	$ 6,100	$ 5,200

- Details

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Period Type:

Thyroid Cytopathology Partners (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Thyroid Cytopathology Partners
Outstanding obligations	$ 3,081		$ 3,081		$ 5,085
Thyroid Cytopathology Partners
Thyroid Cytopathology Partners
Notice of intent not to renew period	12 months
Expenses for cytopathology testing and evaluation services	$ 1,300	$ 1,200	3,800	$ 3,500
Outstanding obligations	870		870		$ 820
Reduction to rent expense for TCP's portion of costs for subleased space	$ 24	$ 23	$ 70	$ 67

Income Taxes (Details)	3 Months Ended
Income Taxes (Details)	Sep. 30, 2016 USD ($)
Income Tax Disclosure [Abstract]
Unrecognized tax benefit	$ 2,100,000
Interest expense or penalties related to unrecognized tax benefits	$ 0

Subsequent Event (Details) - Subsequent Event $ / shares in Units, $ in Millions	Nov. 01, 2016 USD ($) $ / shares shares
Subsequent Event [Line Items]
Sale of stock, consideration received on transaction, gross \| $	$ 34.3
Common Stock
Subsequent Event [Line Items]
Sale of stock, number of shares issued in transaction	5,000,000
Sale of stock, price per share (in usd per share) \| $ / shares	$ 6.00
Common Stock \| Over-Allotment Option
Subsequent Event [Line Items]
Sale of stock, number of shares issued in transaction	750,000