Diadexus (VXGN) 10-Q 5 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 31, 2013
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'DDXS	'
Entity Registrant Name	'diaDexus, Inc.	'
Entity Central Index Key	'0001036968	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Smaller Reporting Company	'
Entity Common Stock, Shares Outstanding	'	54,725,685

CONDENSED_BALANCE_SHEETS

CONDENSED BALANCE SHEETS (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$12,176	$12,851
Short-term investment securities	'	747
Accounts receivable	2,777	2,789
Inventories	567	134
Assets held for sale	'	300
Prepaid expenses and other current assets	938	871
Total current assets	16,458	17,692
Restricted cash	1,400	1,400
Property and equipment, net	1,005	1,250
Other long-term assets	92	142
Total assets	18,955	20,484
Current liabilities:	'	'
Accounts payable	641	469
Notes payable, current portion	1,214	272
Deferred revenues, current portion	306	317
Deferred rent, current portion	32	'
Unfavorable lease obligations	669	588
Accrued and other current liabilities	2,330	1,953
Total current liabilities	5,192	3,599
Non-current portion of notes payable	3,709	4,621
Non-current portion of deferred revenue	'	225
Non-current portion of deferred rent	349	363
Non-current portion of unfavorable lease obligation	1,958	2,475
Other long term liabilities	385	346
Total liabilities	11,593	11,629
Commitments and contingencies (Note 14)	'	'
Stockholders' equity:	'	'
Preferred stock, $0.01 par value, 19,979,500 shares authorized; none issued and outstanding	'	'
Common stock, $0.01 par value; 100,000,000 shares authorized; 54,698,713 and 53,890,314 shares issued and outstanding at September 30, 2013 and December 31, 2012, respectively	547	539
Additional paid-in capital	206,517	206,048
Accumulated deficit	-199,702	-197,732
Total stockholders' equity	7,362	8,855
Total liabilities and stockholders' equity	$18,955	$20,484

CONDENSED_BALANCE_SHEETS_Paren

CONDENSED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]	'	'
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	19,979,500	19,979,500
Preferred stock, shares issued	'	'
Preferred stock, shares outstanding	'	'
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	54,698,713	53,890,314
Common stock, shares outstanding	54,698,713	53,890,314

CONDENSED_STATEMENTS_OF_COMPRE

CONDENSED STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues:	'	'	'	'
Product sales	$6,314	$4,943	$17,915	$12,775
Royalty revenue	'	279	18	2,353
License revenue	76	76	229	229
Total revenues	6,390	5,298	18,162	15,357
Operating costs and expenses:	'	'	'	'
Product costs	1,753	1,558	5,468	4,875
Sales and marketing	1,749	1,297	5,671	3,929
Research and development	1,252	912	3,515	3,297
General and administrative	1,891	1,674	5,538	5,354
Total operating costs and expenses	6,645	5,441	20,192	17,455
Loss from operations	-255	-143	-2,030	-2,098
Interest income, interest expense and other income (expense), net:	'	'	'	'
Interest income	1	3	3	14
Interest expense	-93	-99	-278	-302
Other income (expense), net	-7	-1	340	-4
Loss before income tax	-354	-240	-1,965	-2,390
Income tax	'	1	-5	-2
Net loss	-354	-239	-1,970	-2,392
Basic and diluted net loss per share:	($0.01)	'	($0.04)	($0.05)
Weighted average shares used in computing basic and diluted net loss per share	54,466,489	53,215,893	54,194,316	53,117,270
Comprehensive loss:	'	'	'	'
Net change in unrealized gain/(loss) on available-for-sale securities	'	1	'	5
Comprehensive loss	($354)	($238)	($1,970)	($2,387)

CONDENSED_STATEMENTS_OF_CASH_F

CONDENSED STATEMENTS OF CASH FLOWS (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Operating activities:	'	'
Net loss	($1,970)	($2,392)
Adjustments to reconcile net loss to net cash used in operating activities:	'	'
Loss (gain) on disposal of property and equipment and assets held for sale	-340	4
Depreciation and amortization	401	379
Stock-based compensation	432	257
Amortization on investments	'	26
Provision for rebate reserve (reversal)	'	-20
Provision for doubtful account (reversal)	'	-4
Noncash other interest expense	23	21
Noncash interest associated with notes payable	75	99
Inventory written off	'	31
Unfavorable lease	-436	-365
Changes in operating assets and liabilities	'	'
Accounts receivable	12	-39
Inventory	-433	-113
Prepaid expenses, other current assets and other long-term assets	-46	3
Accounts payable	196	-493
Accrued liabilities and other long term liabilities	404	-340
Deferred rent	18	72
Deferred revenue	-236	-233
Net cash used in operating activities	-1,900	-3,107
Investing activities:	'	'
Purchases of property and equipment	-207	-567
Proceeds from sales of assets	640	2
Restricted cash	'	400
Maturities of available-for-sale investments	747	6,721
Purchases of available-for-sale investments	'	-996
Net cash provided by investing activities	1,180	5,560
Financing activities:	'	'
Proceeds from issuance of common stock	45	68
Debt issuance costs	'	-50
Net cash provided by financing activities	45	18
Net increase (decrease) in cash and cash equivalents	-675	2,471
Cash and cash equivalents, beginning of period	12,851	10,484
Cash and cash equivalents, end of period	12,176	12,955
Supplemental disclosure:	'	'
Cash paid for interest	197	201
Net change in accounts payable from acquisition of property and equipment	-24	-78
Net change in accrued liabilities from acquisition of property and equipment	-27	-195
Debt issuance costs in accounts payable and accrued liabilities	'	$48

Business_Overview

Business Overview	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Business Overview	'
	1. Business Overview
	Formation of the Company
	diaDexus, Inc., a Delaware corporation (the “Company”), is a life sciences company focused on developing and commercializing proprietary cardiovascular diagnostic products addressing unmet needs in cardiovascular disease. The Company is the successor to a company initially formed as a joint venture between SmithKlineBeecham Corporation (now GlaxoSmithKline LLC (“GlaxoSmithKline”)) and Incyte Pharmaceuticals, Inc. Upon formation, SmithKlineBeecham Corporation granted the Company an exclusive license to certain diagnostic intellectual property, including exclusive rights to develop diagnostic assays for Lp-PLA2, an inflammatory marker of cardiovascular risk.
	The Company’s products, PLAC® Tests, provide information, over and above traditional risk factors, to help identify individuals at increased risk of suffering a heart attack or stroke. Some of these events may be reduced with earlier detection and more aggressive risk-reducing strategies, including treatment to lower LDL-cholesterol goals with statins. The Company has commercialized two PLAC Tests:
	1) One test, the PLAC Test ELISA Kit, measures the mass of circulating Lp-PLA2 in the blood. The PLAC Test ELISA Kit is the only Lp-PLA2 blood test cleared by the US Food and Drug Administration (the “FDA”) to aid in assessing risk for both coronary heart disease and ischemic stroke associated with atherosclerosis.
	2) The second test, the PLAC Test for Lp-PLA2 Activity, is an enzyme assay for the quantitative determination of Lp-PLA2 activity levels in human plasma and serum on automated clinical chemistry analyzers, to be used in conjunction with clinical evaluation and patient risk assessment as an indicator of atherosclerotic cardiovascular disease.
	The Company is currently commercializing the PLAC Test ELISA Kit primarily in the United States and Europe and the PLAC Test for Lp-PLA2 Activity primarily in Europe.
	The Company has incurred substantial losses since its inception, and expects to continue to incur net losses for at least the next few years. To date, the Company has funded its operations primarily through private placements of equity and debt financing, as well as through revenue generated from the sale of products.
	In September 2011, the Company entered into a loan and security agreement with Comerica Bank, which was amended in September 2012 (Note 9) and again in October 2013 (Note 16). This loan contains various covenants. If the Company breaches any of these covenants or is unable to make a required payment of principal or interest, or experiences a material adverse change to its business, it could result in a default under the loan. Additionally, the Company is required to (i) maintain a liquidity ratio of 1.25 to 1 and (ii) ensure its cumulative net loss does not exceed $6,000,000 beginning July 1, 2013, and failure to do so could result in a default under the loan. Upon the occurrence of an event of default under the loan, the bank could elect to declare all amounts outstanding to be immediately due and payable. If the Company is unable to repay those amounts, the bank could proceed against the collateral granted to them to secure such indebtedness. The Company has pledged substantially all of its assets, other than its intellectual property, as collateral under the loan. The Company’s future liquidity requirements may increase beyond currently expected levels if it fails to maintain compliance with its covenants. In order to meet the future liquidity needs, the Company may become reliant on additional equity and/or debt financing. Additional funding may not be available when needed or on terms acceptable to the Company. Any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. The Company cannot assure you that it will be able to raise any such additional funding.
	All references in these notes to financial statements to the “Company,” “we,” “us” and “our” refer to diaDexus, Inc. (f/k/a VaxGen, Inc.), a Delaware corporation, unless the context requires otherwise.
	PLAC ELISA Test
	The Company introduced its initial PLAC Test ELISA Kit product in 2004. The PLAC Test ELISA Kit uses microplate technologies to measure levels of Lp-PLA2. The infrastructure for performing microplate tests typically exists only at large and midsize clinical reference laboratories and large hospitals, which must be certified by the US Department of Health and Human Services (“DHHS”) for high-complexity diagnostics under the Clinical Laboratory Improvement Amendments (“CLIA”). Smaller hospitals and clinics can order the PLAC Test ELISA Kit for their patients from those institutions that are able to perform microplate tests and offer the PLAC Test ELISA Kit. Patients can have their blood drawn at a local laboratory and shipped to the more advanced institutions for analysis. The Company markets the PLAC Test ELISA Kit primarily in the United States and Europe.
	PLAC Activity Test
	The Company introduced the PLAC Test for Lp-PLA2 Activity in Europe in March 2012. This PLAC Test for Lp-PLA2 Activity is an enzyme assay for the quantitative determination of Lp-PLA2 activity levels in human serum or plasma. The PLAC Test for Lp-PLA2 Activity allows for the measurement of Lp-PLA2 using automated clinical chemistry analyzer technology. This clinical chemistry technology is more prevalent than the microplate technology used for the PLAC Test ELISA Kit and is less difficult to operate, such that a broader array of institutions can conduct the test. This group includes clinical laboratories and hospitals of all sizes and physician operated laboratories (“POLs”). In addition, the sample handling requirements are much less stringent for the PLAC Test for Lp-PLA2 Activity compared to the PLAC Test ELISA Kit, allowing greater ease of use for those facilities processing specimens. The Company currently markets the PLAC Test for Lp-PLA2 Activity primarily in Europe for use in conjunction with clinical evaluation and patient risk assessment as an indicator of atherosclerotic cardiovascular disease. The Company affixed the CE marking for this intended use by self-certification in January 2012. The Company plans to pursue 510(k) clearance for this test from the FDA and eventually commercialize this assay format in the United States if the Company obtains FDA clearance.
	In September 2013, the Company had a pre-submission meeting with the FDA, as a result of which the Company is advancing its clinical program to support the submission of the PLAC Test for Lp-PLA2 Activity to the FDA. The Company has partnered with a large longitudinal cardiovascular disease study to validate the PLAC Test for Lp-PLA2 Activity. The Company anticipates that the clinical study sample analysis will be initiated prior to the end of the first quarter of 2014.
	Pipeline
	In the second half of 2012, the Company started a strategic business development process to identify new biomarker assays in the cardiovascular space, for development and sale through our existing channels. The Company continues to anticipate being able to provide an update on this strategic development by the end of first quarter 2014.
	Basis of Presentation
	The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The year-end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP. In the opinion of management, the accompanying unaudited condensed financial statements have been prepared on a consistent basis with the December 31, 2012 audited financial statements and include all adjustments, consisting of normal recurring adjustments, that are necessary to fairly state the Company’s financial position as of September 30, 2013, results of operations for both the three and nine months ended September 30, 2013 and cash flows for the nine months ended September 30, 2013.
	Starting in January 2013, the Company includes excise tax collected from customer product sales. The Company recognized $89,000 and $98,000 in charged excise tax within product revenue and product costs, respectively, for the three months ended September 30, 2013, and $303,000 and $351,000, respectively, for the nine months ended September 30, 2013. For both the three and nine months ended September 30, 2012, there was no excise tax recognized within product revenue and product costs.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	2. Summary of Significant Accounting Policies
	The Company’s significant accounting policies are disclosed in the Company’s annual report on Form 10-K for the year ended December 31, 2012, filed with the Securities and Exchange Commission (“SEC”) on March 11, 2013, and have not changed as of September 30, 2013.
	Recent Accounting Pronouncements
	In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.” ASU 2013-02 amends the accounting guidance for presentation of comprehensive income to improve the reporting of reclassifications out of accumulated other comprehensive income. The amendments do not change the current requirements for reporting net income or other comprehensive income, but do require an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, an entity is required to present, either on the face of the statement where the net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income but only if the amount reclassified is required under GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under GAAP that provide additional detail about these amounts. For public companies, these amendments are effective prospectively for reporting periods beginning after December 15, 2012. The Company adopted the provisions of this guidance during the first quarter of 2013.

Cash_Cash_Equivalents_and_Inve

Cash, Cash Equivalents and Investments	9 Months Ended
	Sep. 30, 2013
Cash And Cash Equivalents [Abstract]	'
Cash, Cash Equivalents and Investments	'
	3. Cash, Cash Equivalents and Investments
	As part of its cash management program, the Company maintains a portfolio of marketable investment securities. The securities are investment grade and generally mature within one year and may include tax exempt securities and certificates of deposit. The fair value of substantially all securities is determined by quoted market prices. The Company maintains its cash in bank accounts, which at times may exceed federally insured limits. The Company has not experienced any losses on such accounts. The Company considers all highly liquid investments purchased with an original maturity of three months or less at the time of purchase to be cash equivalents.
	The following is a summary of cash, cash equivalents, and available-for-sale securities at September 30, 2013 and December 31, 2012 (in thousands):
		September 30, 2013
		Cost Basis		Unrealized		Unrealized		Estimated
				Gains		Losses		Fair Value
	Cash and cash equivalents:
	Cash	$	8,129	$	—	$	—	$	8,129
	Money market funds		4,047		—		—		4,047
	Total cash and cash equivalents	$	12,176	$	—	$	—	$	12,176
		December 31, 2012
		Cost Basis		Unrealized		Unrealized		Estimated
				Gains		Losses		Fair Value
	Cash and cash equivalents:
	Cash	$	6,054	$	—	$	—	$	6,054
	Money market funds		6,797		—		—		6,797
	Total cash and cash equivalents	$	12,851	$	—	$	—	$	12,851
	Available-for-sale marketable securities:
	Certificates of deposits		747		—				747
	Total available-for-sale marketable securities	$	747	$	—	$	—	$	747
	Fair Value Measurements
	In accordance with ASC 820, the Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The guidance establishes three levels of the fair value hierarchy as follows:
	Level 1: Observable inputs, such as quoted prices in active markets for identical assets or liabilities;
	Level 2: Observable inputs other than Level 1 prices, 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 represents the Company’s fair value hierarchy for its financial assets (cash equivalents and investments) measured at fair value on a recurring basis as of September 30, 2013 and December 31, 2012 (in thousands):
				Fair Value Measurements
		Balance at		Quoted Prices		Significant		Significant
		September 30,		In Active		other		Unobservable
		2013		Markets for		Observable		Inputs
				Identical Assets		Inputs		Level 3
				Level 1		Level 2
	Assets:
	Cash	$	8,129	$	8,129	$	—	$	—
	Money market funds		4,047		4,047		—		—
	Restricted cash		1,400		—		1,400		—
		$	13,576	$	12,176	$	1,400	$	—
				Fair Value Measurements
		Balance at		Quoted Prices		Significant		Significant
		December 31,		In Active		other		Unobservable
		2012		Markets for		Observable		Inputs
				Identical Assets		Inputs		Level 3
				Level 1		Level 2
	Assets:
	Cash	$	6,054	$	6,054	$	—	$	—
	Money market funds		6,797		6,797		—		—
	Certificates of deposit		747		—		747		—
	Restricted cash		1,400		—		1,400		—
		$	14,998	$	12,851	$	2,147	$	—
	The fair value of the notes payable is valued based on Level 2 inputs and approximates its book value. The fair value of the notes payable is based on the present value of expected future cash flows and assumptions about current interest rates and the credit worthiness of the Company. As of September 30, 2013, the notes payable is carried at face value of $5.0 million less any unamortized debt discount.
	The carrying value of other financial instruments, including cash, accounts receivable, accounts payable and other payables, approximates fair value due to their short maturities.

Inventory

Inventory	9 Months Ended
	Sep. 30, 2013
Inventory Disclosure [Abstract]	'
Inventory	'
	4. Inventory
	Inventory consists of the following (in thousands):
		September 30,		December 31,
		2013		2012
	Finished goods	$	428	$	61
	Raw materials		139		73
		$	567	$	134

Assets_Held_For_Sale

Assets Held For Sale

9 Months Ended

Sep. 30, 2013

Text Block [Abstract]

'

Assets Held For Sale

'

5. Assets Held For Sale

Prior to the period reflected in this report, the Company had committed to a plan to sell the equipment related to its manufacturing facility and had determined that these assets met the criteria for, and had been classified as, “held for sale” in accordance with ASC Topic 360. The market approach was used in determining the fair market value of these assets.

Total assets held for sale as of September 30, 2013 and December 31, 2012 are as follows (in thousands):

Fair Value Measurements

Description

Carrying

September 30,

Quoted

Significant

Significant

Nine Months

Value at

2013

Prices in

Other

Unobservable

Ended

September 30,

Active

Observable

Inputs (Level 3)

September 30,

2013

Markets for

Inputs

2013 Total

Identical

(Level 2)

Gains

Assets

(Losses)

(Level 1)

Assets held for sale

$

—

$

—

$

—

$

—

$

—

$

340

Fair Value Measurements

Description

December 31,

Quoted

Significant

Significant

Year Ended

2012

Prices in

Other

Unobservable

December 31,

Active

Observable

Inputs

2012 Total

Markets for

Inputs

(Level 3)

Gains

Identical

(Level 2)

(Losses)

Assets

(Level 1)

Assets held for sale

$

300

$

—

$

—

$

300

$

—

The measurement of the assets held for sale at fair value incorporated significant unobservable inputs as a result of a lack of any available observable market information to determine the fair value. The calculation of the fair value of assets held for sale used a market valuation technique that relied on Level 3 inputs, including quoted prices for similar assets. In 2012, the Company signed an agreement to sell the assets for $695,000, net of disposal costs. All assets were transferred and sold to the purchaser as of September 30, 2013 and the Company recognized losses of $7,000 and gains of $340,000, which are included in the statement of comprehensive loss for the three and nine months ended September 30, 2013, respectively.

Property_Plant_and_Equipment

Property, Plant and Equipment	9 Months Ended
	Sep. 30, 2013
Property Plant And Equipment [Abstract]	'
Property, Plant and Equipment	'
	6. Property, Plant and Equipment
	Property and equipment are recorded at cost. Expenditures for major additions and improvements are capitalized, and maintenance and repairs are charged to expense as incurred. When property and equipment are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations for the respective period. Depreciation is provided over the estimated useful lives of the related assets using the straight-line method for financial statement purposes. The Company uses other depreciation methods for tax purposes where appropriate. The estimated useful lives for significant property and equipment categories are as follows:
	Office and laboratory equipment	3 years
	Computer equipment and software	3 years
	Leasehold improvements	Term of lease agreement
	The following is a summary of property and equipment at cost less accumulated depreciation as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30,			December 31,
		2013			2012
	Laboratory equipment	$	3,207		$	3,149
	Leasehold improvements		602			602
	Computer and software		375			361
	Furniture and fixtures		181			180
	Construction in progress		83			—
			4,448			4,292
	Less: Accumulated depreciation and amortization		(3,443	)		(3,042	)
		$	1,005		$	1,250
	Depreciation and amortization expense was $0.1 million and $0.4 million for the three and nine months ended September 30, 2013, respectively, and $0.1 million and $0.4 million, respectively, for the same periods in 2012.

Total_Accrued_and_Other_Curren

Total Accrued and Other Current Liabilities	9 Months Ended
	Sep. 30, 2013
Payables And Accruals [Abstract]	'
Total Accrued and Other Current Liabilities	'
	7. Total Accrued and Other Current Liabilities
	Total accrued and other current liabilities include the following as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30,		December 31,
		2013		2012
	Accrued payroll and related expenses	$	1,252	$	1,220
	Accrued inventory		323		—
	Accrued consulting expense		143		122
	Accrued collaborative research obligations		82		22
	Accrued sales and excise tax		82		60
	Accrued audit fees		77		73
	Accrued royalty expenses		62		118
	Accrued legal and patent expense		46		87
	Accrued property and equipment		—		27
	Other current liabilities		263		224
	Total accrued and other current liabilities	$	2,330	$	1,953

Concentration_of_Credit_Risk

Concentration of Credit Risk	9 Months Ended
	Sep. 30, 2013
Risks And Uncertainties [Abstract]	'
Concentration of Credit Risk	'
	8. Concentration of Credit Risk
	Revenues from the following customers represented a significant portion of total revenue for the three and nine months ended September 30, 2013 and 2012 and accounts receivable as of September 30, 2013 and December 31, 2012:
		Revenue												Accounts Receivable
		Three Months Ended						Nine Months Ended						September 30,			December 31,
		September 30,						September 30,
		2013			2012			2013			2012			2013			2012
	Customer A		43	%		44	%		44	%		45	%		40	%		34	%
	Customer B		14	%		15	%		13	%		13	%		10	%		14	%
	Customer C		10	%		6	%		9	%		6	%		2	%		2	%
	Customer D		8	%		1	%		5	%		2	%		21	%		3	%
	Customer E		6	%		6	%		6	%		6	%		10	%		10	%
	Customer F		4	%		6	%		5	%		4	%		6	%		10	%
	Total		85	%		78	%		82	%		76	%		89	%		73	%

Notes_Payable

Notes Payable	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Notes Payable	'
	9. Notes Payable
	In September 2011, the Company entered into a Loan and Security Agreement with Comerica Bank to borrow up to $5,000,000, the entire amount of which was borrowed at a rate of 5.25% per annum. Prior to the amendments described below, the loan was payable in 36 monthly installments which were to begin in October 2012, with interest only payments being made from October 2011 to September 2012. The Company paid an initial fee of $25,000 for access to this loan and will be required to pay an additional fee of $100,000 following repayment of the loan. The Company may prepay all, but not less than all, of the loaned amount with 30 days advance notice to Comerica. In connection with the loan, the Company issued a warrant to Comerica to purchase 480,769 shares of the Company’s common stock at an exercise price of $0.26 per share. Comerica exercised this warrant in August 2013 (Note 13).
	The term loan is secured by a first priority security interest on all of the Company’s assets excluding the Company’s intellectual property (except for rights to payment related to the sale, licensing or disposition of such intellectual property rights) and property not assignable without consent by a third party or with respect to which granting a security interest is contrary to law. In addition, the Company has agreed not to sell, assign, transfer, pledge or otherwise encumber its intellectual property to another entity without the bank’s approval or consent, subject to certain exceptions.
	The Loan and Security Agreement contains customary representations and warranties, covenants, events of defaults and termination provisions. The affirmative covenants include, among other things, that the Company timely file taxes, maintain good standing and government compliance, achieve at least 80% of specified monthly revenue projections calculated on a trailing three months basis, maintain primary depository and operating accounts with the bank, maintain liability and other insurance, and provide security interests to the bank in the collateral of any subsidiary formed or acquired by the Company in the future. The negative covenants provide, among other things, that without the prior consent of the bank, the Company may not dispose of certain assets, engage in certain business combinations or acquisitions, incur additional indebtedness or encumber any of the Company’s property (subject to certain exceptions), pay dividends on the Company’s capital stock or make prohibited investments. The Loan and Security Agreement provides that an event of default will occur if, among other triggers, (1) the Company defaults in the payment of any amount payable under the agreement when due, (2) there occurs any circumstance or circumstances that could reasonably be expected to result in a material adverse effect on the Company’s business, operations or condition, or on the Company’s ability to perform its obligations under the agreement, (3) the Company becomes insolvent, (4) the Company undergoes a change in control or (5) the Company breaches any negative covenants or certain affirmative covenants in the agreement or, subject to a cure period, otherwise neglects to perform or observe any material item in the agreement. The repayment of the term loan may be accelerated, at the option of the bank, following the occurrence of an event of default, which would require the Company to pay to the bank an amount equal to the sum of: (i) all outstanding principal plus accrued interest, (ii) the final payment, and (iii) all other sums that shall have become due and payable but have not been paid, including interest at the default rate with respect to any past due amounts. As of September 30, 2013, the Company was in compliance with all the covenants.
	In September 2012, the Company and Comerica Bank entered into an Amended and Restated Loan and Security Agreement (the “First Amended Loan and Security Agreement”). The First Amended Loan and Security Agreement extended the interest-only payment period for an additional twelve months, through September 23, 2013, and extended the maturity date for an additional twelve months, to September 23, 2016. The First Amended Loan and Security Agreement also reduced the monthly principal payments by amortizing the loan over a 48 month basis, resulting in an increased balloon payment of principal on the maturity date. The Company paid a fee of $50,000 for access to the First Amended Loan and Security Agreement. Pursuant to the First Amended Loan and Security Agreement, the Company issued a warrant to Comerica Bank to purchase 168,919 shares of its common stock. The warrant has an exercise price of $0.37 per share and will expire on September 11, 2019 (Note 13).
	The Company accounted for the First Amended Loan and Security Agreement as a debt modification since the terms of the original Loan and Security Agreement and the First Amended Loan and Security Agreement were not substantially different, and the present value of cash flows of the modified instrument was within 10% of the cash flows of the original debt instrument. Accordingly, debt discount of $48,000 associated with the First Amended Loan and Security Agreement, and unamortized debt discount of $72,000 from the original Loan and Security Agreement will be amortized as an adjustment of interest expense over the term of the First Amended Loan and Security Agreement using the effective interest method.
	As of September 30, 2013, future minimum payments for the notes payable are as follows(in thousands):
	2013 (remainder of year)	$	377
	2014		1,466
	2015		1,400
	2016		2,357
	Total minimum payments		5,600
	Less: Amount representing interest		(600	)
	Present value of minimum payments		5,000
	Less: Unamortized debt discount		(77	)
	Notes payable, net		4,923
	Less: Notes payable, current portion		(1,214	)
	Non-current portion of notes payable	$	3,709

Common_Stock

Common Stock	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Common Stock	'
	10. Common Stock
	On July 15, 2011, the Company amended its certificate of incorporation to increase the number of authorized shares of its common stock, par value of $0.01 per share, to 100,000,000. The holders of common stock are entitled to receive dividends, as, when and if declared by the Company’s Board of Directors out of funds legally available for distribution, subject to the restriction on dividends contained in the Company’s loan agreement with Comerica Bank (Note 9).

Basic_and_Diluted_Net_Loss_per

Basic and Diluted Net Loss per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Basic and Diluted Net Loss per Share	'
	11. Basic and Diluted Net Loss per Share
	Basic net loss per common share is based on the weighted average number of common shares outstanding during the period. Diluted net loss per common share is based on the weighted average number of common shares and other dilutive securities outstanding during the period, provided that including these dilutive securities does not increase the net loss per share.
	The effect of the options, restricted stock units (“RSUs”) and warrants was anti-dilutive for the nine months ended September 30, 2013 and 2012. The following table shows the total outstanding securities considered anti-dilutive, and therefore excluded from the computation of diluted net loss per share (in thousands):
		As of
		September 30,
		2013		2012
	Options to purchase common stock		9,778		11,025
	Restricted stock units		42		—
	Warrants to purchase common stock		169		650
	Total		9,989		11,675

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Compensation	'
	12. Stock-Based Compensation
	Stock Option Plans
	2012 Equity Incentive Award Plan
	The Company’s stockholders approved the 2012 Equity Incentive Award Plan (the “2012 Plan”) at the 2012 Annual Meeting of Stockholders on May 17, 2012 and approved 3,000,000 shares of common stock authorized for issuance. On May 17, 2012, all shares of common stock that remained available for issuance under the 1996 Stock Option Plan (the “1996 Plan”) and the 1998 Director Stock Option Plan (the “Director Plan”) were added to the shares reserved under the 2012 Plan. In addition, pursuant to the 2012 Plan, any shares of common stock subject to awards previously granted under the 1996 Plan, the Director Plan and certain non-plan option agreements entered into with certain individuals as of March 31, 2012 that terminate, expire or lapse will become available for issuance under the 2012 Plan. Options granted under the 2012 Plan may be designated as qualified or nonqualified at the discretion of the Compensation Committee of the Board of Directors. Generally, shares issuable upon exercise of options vest ratably over four years, beginning one year from the date of grant; however, options can vest upon grant. Option terms expire no later than 10 years from the date of grant, or 5 years from the date the option is granted to a greater than 10% stockholder. The stock options are exercisable at not less than the fair market value of the stock at the date of grant, or not less than 110% of the fair market value of the stock at the date of grant if granted to a greater than 10% stockholder. As of September 30, 2013, options to purchase 3,031,850 shares of common stock were outstanding and 2,325,617 shares were available for issuance under the 2012 Plan.
	1996 Stock Option Plan
	The 1996 Plan initially had 4,750,000 shares of common stock authorized for issuance and a provision that automatically increased this number by 3.5% of the issued and outstanding common stock on the last trading day of the December immediately preceding each fiscal year through January 2007. Options granted under the 1996 Plan were designated as qualified or nonqualified at the discretion of the Compensation Committee of the Board of Directors. Generally, shares issuable upon exercise of options vest ratably over four years, beginning one year from the date of grant; however, options could vest upon grant. All options expire no later than 10 years from the date of grant. Qualified stock options are exercisable at not less than the fair market value of the stock at the date of grant, and nonqualified stock options are exercisable at prices determined at the discretion of the Board of Directors, but not less than 85% of the fair market value of the stock at the date of grant. On May 17, 2012, the 1996 Plan was terminated in connection with the effectiveness of the 2012 Plan. All 1,555,492 shares that were available for issuance under the 1996 Plan were transferred to the 2012 Plan, and the 6,398,904 shares that were subject to awards outstanding under the 1996 Plan remained outstanding pursuant to the terms of the 1996 Plan. As of September 30, 2013, options to purchase 3,050,288 shares of common stock were outstanding pursuant to the terms of the 1996 Plan.
	1998 Director Stock Option Plan
	The Director Plan for non-employee directors had 300,000 shares of common stock authorized for issuance. On May 17, 2012, the Director Plan was terminated in connection with the effectiveness of the 2012 Plan. All 130,000 shares that were available for issuance under the Director Plan were transferred to the 2012 Plan, and the 170,000 shares that were subject to awards outstanding under the Director Plan remained outstanding pursuant to the terms of the Director Plan. As of September 30, 2013, options to purchase 60,000 shares of common stock were outstanding pursuant to the terms of the Director Plan.
	Non-Plan Grants
	In October 2004, the Company granted non-qualified stock options to purchase 30,000 shares of common stock outside of the Company’s stock option plans to its former director with an exercise price of $12.27 per share. These options were granted with terms that are substantially in accordance with the Company’s standard stock option terms. As of September 30, 2013, all of these options remained outstanding.
	In September 2011, the Company granted non-qualified stock options to purchase 1,530,000 shares of common stock outside of the Company’s stock option plans to its current Chief Executive Officer with an exercise price of $0.25 per share. These options were granted with terms that are substantially in accordance with the Company’s standard stock option terms. As of September 30, 2013, all of these options remained outstanding.
	In October 2011, the Company granted non-qualified stock options to purchase 1,130,000 shares of common stock outside of the Company’s stock option plans to its current Chief Business Officer with an exercise price of $0.26 per share. These options were granted with terms that are substantially in accordance with the Company’s standard stock option terms. As of September 30, 2013, 1,018,458 of these options remained outstanding.
	On February 1, 2012, the Company granted non-qualified stock options to purchase 1,060,000 shares of common stock outside of the Company’s stock option plans to its current Chief Financial Officer with an exercise price of $0.28 per share. These options were granted with terms that are substantially in accordance with the Company’s standard stock option terms. As of September 30, 2013, 1,057,460 of these options remained outstanding.
	Restricted Stock Units
	On August 6, 2013, the Company awarded an aggregate of 41,708 RSUs to its directors with a grant-date fair value equal to $55,472 in the aggregate. Each RSU entitles the recipient to received one share of the Company’s common stock upon vesting. RSUs awarded to directors generally vest annually. As of September 30, 2013, all of these RSUs remained outstanding and none was vested.
	The following table summarizes stock compensation expense related to employee stock options and employee stock-based compensation for the three and nine months ended September 30, 2013 and 2012, which was incurred as follows (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
	Stock compensation expense:
	Product costs	$	7		$	3		$	17		$	8
	Research and development		38			19			92			50
	Sales and marketing		29			19			87			48
	General and administrative		119			52			236			151
	Total stock compensation expense	$	193		$	93		$	432		$	257
	Stock-based compensation expense recognized during the three and nine months ended September 30, 2013 and 2012 includes compensation expense for stock-based awards granted to employees based on the grant date fair value estimated in accordance with the provisions of ASC 718. As of September 30, 2013, the total remaining unrecognized cost was approximately $1.1 million to be recognized over approximately three years.
	Valuation Assumptions
	The compensation expense related to stock options recognized was determined using the Black-Scholes option valuation model. Option valuation models require the input of subjective assumptions and these assumptions can vary over time. The weighted average assumptions used were as follows:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
	Dividend yield		0	%		0	%		0	%		0	%
	Risk-free interest rate		1.13	%		0.58	%		0.93	%		0.54	%
	Expected volatility		79.42	%		95.47	%		84.66	%		95.98	%
	Forfeiture rate		13.9	%		13.24	%		13.9	%		13.24	%
	Expected term (years)		4.06			4.12			4.06			4.12
	Fair value per share at grant date	$	0.75		$	0.22		$	0.61		$	0.21
	For the three and nine months ended September 30, 2013, volatility assumption was determined by examining the historical volatilities for industry peers and the trading history for the Company’s common stock. For the three and nine months ended September 30, 2012, volatility assumption was determined by examining the historical volatilities for industry peers only as the Company did not have sufficient trading history for the Company’s common stock during that period. The Company will continue to incorporate its historical stock price volatility and expected term assumption for future periods. The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of the Company’s stock options. The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. Different estimates of volatility and expected term could materially change the value of an option and the resulting expense. The expected term of stock options represents the weighted-average period the stock options are expected to remain outstanding and is based on the options’ vesting terms, contractual terms and historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior.
	Employee Stock-Based Compensation
	The table below presents information related to stock option activity for the nine months ended September 30, 2013, as follows:
		Number of			Weighted-			Weighted-			Aggregate
		Options			Average			Average			Intrinsic
		Outstanding			Exercise			Remaining			Value
					Price			Contractual
								Term
								(In years)
	Outstanding at December 31, 2012		8,963,226		$	0.47
	Options granted		1,563,910			1
	Options exercised		(611,596	)		0.26
	Options cancelled/forfeited/expired		(137,484	)		3.92
	Outstanding at September 30, 2013		9,778,056		$	0.52			8.15		$	13,734,086
	Exercisable at September 30, 2013		5,110,489		$	0.52			7.64		$	7,639,909
	Vested and expected to vest at September 30, 2013		9,031,664		$	0.52			8.1		$	12,784,188

Stock_Warrants

Stock Warrants	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Stock Warrants	'
	13. Stock Warrants
	The Company issues warrants to investors as part of its overall financing strategy and to vendors in order to reduce costs. In connection with the Loan and Security Agreement the Company entered into with Comerica Bank in September 2011 (Note 9), the Company issued to Comerica a warrant to purchase 480,769 shares of the Company’s common stock, at an exercise price of $0.26 per share. The initial fair value of the warrant was calculated using the Black-Scholes option pricing model and the following assumptions: volatility of 88.03%, risk-free interest rate of 1.36%, exercise price of $0.26 and an expected life of 7 years. The fair value of the warrant was determined to be $94,000 and was recorded as equity in additional paid-in-capital and a discount to the carrying value of the loan. Through August 2012, the discount was amortized to interest expense using the effective interest rate method over the 48-month term of the original loan. Beginning in September 2012, and in connection with the First Amended Loan and Security Agreement (Note 9), the unamortized discount was recognized over the remaining term of the amended loan, which was to mature in September 2016. Comerica exercised this warrant in August 2013.
	In connection with the First Amended Loan Agreement, the Company issued to Comerica a warrant to purchase 168,919 shares of the Company’s common stock, at an exercise price of $0.37 per share. This warrant expires in September 2019. The initial fair value of the warrant was calculated using the Black-Scholes option pricing model and the following assumptions: volatility of 89.87%, risk-free interest rate of 1.03%, exercise price of $0.37 and an expected life of 7 years. The fair value of the warrant was determined to be $48,000 and was recorded as equity in additional paid-in-capital and a discount to the carrying value of the loan. As of September 30, 2013, the discount was being amortized to interest expense using the effective interest rate method over the remaining term of the amended loan, which had a maturity date in September 2016.
	In August 2013, we issued 386,784 shares of common stock pursuant to a cashless exercise of Comerica’s warrant to purchase 480,769 shares at an exercise price of $0.26 per share. As of September 30, 2013, there were warrants outstanding to purchase 168,919 shares of the Company’s common stock, with an exercise price of $0.37 per share and an aggregate exercise price of $63,000.
	The following table summarizes information about all warrants outstanding as of September 30, 2013:
		Warrants Outstanding and Exercisable
	Exercise Price	Number		Weighted		Weighted
		Outstanding		Average		Average
				Remaining		Exercise
				Contractual		Price
				Life (In Years)
	$0.37		168,919		5.95	$	0.37

Leases_Commitments_and_Conting

Leases, Commitments and Contingencies	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Leases, Commitments and Contingencies	'
	14. Leases, Commitments and Contingencies
	The Company leases an office and laboratory facility (the “349 Facility”) under a long-term, non-cancelable operating lease agreement, which expires in December 2016.
	In 2010, the Company recorded a lease obligation associated with the 349 Facility, which contained a lease payment that exceeded current market rates. Accordingly, the Company recognized a $4.1 million unfavorable lease obligation, included in the accompanying balance sheet. The Company amortizes the unfavorable lease obligation using the effective interest rate method.
	Rent expense for the Company’s facilities was $484,000 and $1.5 million for the three and nine months ended September 30, 2013, respectively, and $508,000 and $1.5 million, respectively, for the same periods in 2012. The terms of the lease for the 349 Facility provides for rental payments on a graduated scale. The Company recognizes rent expense on a straight-line basis over the lease period. Deferred rent of $381,000 and $363,000 at September 30, 2013 and December 31, 2012, respectively, is included in the accompanying balance sheets.
	As of September 30, 2013, future minimum lease payments under non-cancelable operating leases are as follows (in thousands):
		Operating
		Leases
	2013 (remainder of year)	$	626
	2014		2,581
	2015		2,658
	2016		2,738
	Total minimum lease payments	$	8,603

Income_Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	15. Income Taxes
	Provision for Income Tax
	The Company’s effective tax rate is 0% for income tax for both the three and nine months ended September 30, 2013 and the Company expects that its effective tax rate for the full year 2013 will be 0%. Based on the weight of available evidence, including cumulative losses since inception and expected future losses, the Company has determined that it is more likely than not that the deferred tax asset amount will not be realized and therefore a valuation allowance has been provided on net deferred tax assets.
	Under the provisions of Section 382 and 383 of the Internal Revenue Code (the “Code”), a change of control, as defined in the Code, may impose an annual limitation on the amount of the Company’s net operating loss and tax credit carryforwards, and other tax attributes, that can be used to reduce future tax liabilities.
	The Company files U.S. Federal and multiple state tax returns. The Company is currently not subject to any income tax examinations. Due to the Company’s losses, generally all years remain open.
	Uncertain Tax Positions
	Effective January 1, 2009, the Company adopted ASC 740-10, which requires that the Company recognize the financial statement effects of a tax position when it becomes more likely than not, based upon the technical merits, that the position will be sustained upon examination.
	The gross amount of unrecognized tax benefits as of September 30, 2013 is $1.6 million related to the reserve on research and development credits, none of which will affect the effective tax rate if recognized due to the valuation allowance. The Company does not expect any material changes in the next 12 months in unrecognized tax benefits.
	The Company recognizes interest and/or penalties related to uncertain tax positions. To the extent accrued interest and penalties do not ultimately become payable, amounts accrued will be reduced and reflected in the period that such determination is made. The interest and penalties are recognized as other expense and not tax expense. The Company currently has no interest and penalties related to uncertain tax positions.

Subsequent_Events

Subsequent Events	9 Months Ended
	Sep. 30, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	16. Subsequent Events
	In October 2013, the Company and Comerica Bank entered into a Second Amended and Restated Loan and Security Agreement (the “Second Amended Loan and Security Agreement”). The Second Amended Loan and Security Agreement increased the aggregate principal amount of the loan by $5 million, the entire amount of which was borrowed on October 17, 2013, for a total outstanding principal amount of $10 million, with interest at a fixed per annum rate equal to 6.45%. The Second Amended Loan and Security Agreement also extends the interest-only payment period for an additional three months, through December 31, 2013, and extends the maturity date for an additional three months, to December 1, 2016. The Second Amended Loan and Security Agreement also reduces the monthly principal payments by amortizing the loan over a 42 month basis, resulting in an increased balloon payment of principal on the maturity date. Additionally, the Company is required to (i) maintain a liquidity ratio of 1.25 to 1 and (ii) ensure its cumulative net loss does not exceed $6,000,000 beginning July 1, 2013. The Company paid a fee of $50,000 for access to the Second Amended Loan and Security Agreement. Pursuant to the Second Amended Loan and Security Agreement, the Company issued a warrant to Comerica Bank to purchase 96,685 shares of its common stock. The warrant has an exercise price of $1.81 per share and will expire on October 17, 2020.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Recent Accounting Pronouncements	'
	Recent Accounting Pronouncements
	In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income.” ASU 2013-02 amends the accounting guidance for presentation of comprehensive income to improve the reporting of reclassifications out of accumulated other comprehensive income. The amendments do not change the current requirements for reporting net income or other comprehensive income, but do require an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component. In addition, an entity is required to present, either on the face of the statement where the net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income but only if the amount reclassified is required under GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under GAAP that provide additional detail about these amounts. For public companies, these amendments are effective prospectively for reporting periods beginning after December 15, 2012. The Company adopted the provisions of this guidance during the first quarter of 2013.

Cash_Cash_Equivalents_and_Inve1

Cash, Cash Equivalents and Investments (Tables)	9 Months Ended
	Sep. 30, 2013
Cash And Cash Equivalents [Abstract]	'
Cash, Cash Equivalents, and Available-for-Sale Securities	'
	The following is a summary of cash, cash equivalents, and available-for-sale securities at September 30, 2013 and December 31, 2012 (in thousands):
		September 30, 2013
		Cost Basis		Unrealized		Unrealized		Estimated
				Gains		Losses		Fair Value
	Cash and cash equivalents:
	Cash	$	8,129	$	—	$	—	$	8,129
	Money market funds		4,047		—		—		4,047
	Total cash and cash equivalents	$	12,176	$	—	$	—	$	12,176
		December 31, 2012
		Cost Basis		Unrealized		Unrealized		Estimated
				Gains		Losses		Fair Value
	Cash and cash equivalents:
	Cash	$	6,054	$	—	$	—	$	6,054
	Money market funds		6,797		—		—		6,797
	Total cash and cash equivalents	$	12,851	$	—	$	—	$	12,851
	Available-for-sale marketable securities:
	Certificates of deposits		747		—				747
	Total available-for-sale marketable securities	$	747	$	—	$	—	$	747
Fair Value Hierarchy for Financial Assets Measured at Fair Value on Recurring Basis	'
	The following table represents the Company’s fair value hierarchy for its financial assets (cash equivalents and investments) measured at fair value on a recurring basis as of September 30, 2013 and December 31, 2012 (in thousands):
				Fair Value Measurements
		Balance at		Quoted Prices		Significant		Significant
		September 30,		In Active		other		Unobservable
		2013		Markets for		Observable		Inputs
				Identical Assets		Inputs		Level 3
				Level 1		Level 2
	Assets:
	Cash	$	8,129	$	8,129	$	—	$	—
	Money market funds		4,047		4,047		—		—
	Restricted cash		1,400		—		1,400		—
		$	13,576	$	12,176	$	1,400	$	—
				Fair Value Measurements
		Balance at		Quoted Prices		Significant		Significant
		December 31,		In Active		other		Unobservable
		2012		Markets for		Observable		Inputs
				Identical Assets		Inputs		Level 3
				Level 1		Level 2
	Assets:
	Cash	$	6,054	$	6,054	$	—	$	—
	Money market funds		6,797		6,797		—		—
	Certificates of deposit		747		—		747		—
	Restricted cash		1,400		—		1,400		—
		$	14,998	$	12,851	$	2,147	$	—

Inventory_Tables

Inventory (Tables)	9 Months Ended
	Sep. 30, 2013
Inventory Disclosure [Abstract]	'
Inventory	'
	Inventory consists of the following (in thousands):
		September 30,		December 31,
		2013		2012
	Finished goods	$	428	$	61
	Raw materials		139		73
		$	567	$	134

Assets_Held_For_Sale_Tables

Assets Held For Sale (Tables)

9 Months Ended

Sep. 30, 2013

Text Block [Abstract]

'

Assets Held for Sale

'

Total assets held for sale as of September 30, 2013 and December 31, 2012 are as follows (in thousands):

Fair Value Measurements

Description

Carrying

September 30,

Quoted

Significant

Significant

Nine Months

Value at

2013

Prices in

Other

Unobservable

Ended

September 30,

Active

Observable

Inputs (Level 3)

September 30,

2013

Markets for

Inputs

2013 Total

Identical

(Level 2)

Gains

Assets

(Losses)

(Level 1)

Assets held for sale

$

—

$

—

$

—

$

—

$

—

$

340

Fair Value Measurements

Description

December 31,

Quoted

Significant

Significant

Year Ended

2012

Prices in

Other

Unobservable

December 31,

Active

Observable

Inputs

2012 Total

Markets for

Inputs

(Level 3)

Gains

Identical

(Level 2)

(Losses)

Assets

(Level 1)

Assets held for sale

$

300

$

—

$

—

$

300

$

—

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	9 Months Ended
	Sep. 30, 2013
Property Plant And Equipment [Abstract]	'
Schedule of Estimated Useful Lives for Significant Property and Equipment	'
	The Company uses other depreciation methods for tax purposes where appropriate. The estimated useful lives for significant property and equipment categories are as follows:
	Office and laboratory equipment	3 years
	Computer equipment and software	3 years
	Leasehold improvements	Term of lease agreement
Property and Equipment at Cost Less Accumulated Depreciation	'
	The following is a summary of property and equipment at cost less accumulated depreciation as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30,			December 31,
		2013			2012
	Laboratory equipment	$	3,207		$	3,149
	Leasehold improvements		602			602
	Computer and software		375			361
	Furniture and fixtures		181			180
	Construction in progress		83			—
			4,448			4,292
	Less: Accumulated depreciation and amortization		(3,443	)		(3,042	)
		$	1,005		$	1,250

Total_Accrued_and_Other_Curren1

Total Accrued and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2013
Payables And Accruals [Abstract]	'
Accrued and Other Current Liabilities	'
	Total accrued and other current liabilities include the following as of September 30, 2013 and December 31, 2012 (in thousands):
		September 30,		December 31,
		2013		2012
	Accrued payroll and related expenses	$	1,252	$	1,220
	Accrued inventory		323		—
	Accrued consulting expense		143		122
	Accrued collaborative research obligations		82		22
	Accrued sales and excise tax		82		60
	Accrued audit fees		77		73
	Accrued royalty expenses		62		118
	Accrued legal and patent expense		46		87
	Accrued property and equipment		—		27
	Other current liabilities		263		224
	Total accrued and other current liabilities	$	2,330	$	1,953

Concentration_of_Credit_Risk_T

Concentration of Credit Risk (Tables)	9 Months Ended
	Sep. 30, 2013
Risks And Uncertainties [Abstract]	'
Revenues from Large Laboratory Customers	'
	Revenues from the following customers represented a significant portion of total revenue for the three and nine months ended September 30, 2013 and 2012 and accounts receivable as of September 30, 2013 and December 31, 2012:
		Revenue												Accounts Receivable
		Three Months Ended						Nine Months Ended						September 30,			December 31,
		September 30,						September 30,
		2013			2012			2013			2012			2013			2012
	Customer A		43	%		44	%		44	%		45	%		40	%		34	%
	Customer B		14	%		15	%		13	%		13	%		10	%		14	%
	Customer C		10	%		6	%		9	%		6	%		2	%		2	%
	Customer D		8	%		1	%		5	%		2	%		21	%		3	%
	Customer E		6	%		6	%		6	%		6	%		10	%		10	%
	Customer F		4	%		6	%		5	%		4	%		6	%		10	%
	Total		85	%		78	%		82	%		76	%		89	%		73	%

Notes_Payable_Tables

Notes Payable (Tables)	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Future Minimum Payments for Notes Payable	'
	As of September 30, 2013, future minimum payments for the notes payable are as follows(in thousands):
	2013 (remainder of year)	$	377
	2014		1,466
	2015		1,400
	2016		2,357
	Total minimum payments		5,600
	Less: Amount representing interest		(600	)
	Present value of minimum payments		5,000
	Less: Unamortized debt discount		(77	)
	Notes payable, net		4,923
	Less: Notes payable, current portion		(1,214	)
	Non-current portion of notes payable	$	3,709

Basic_and_Diluted_Net_Loss_per1

Basic and Diluted Net Loss per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Outstanding Securities Considered Anti-Dilutive, and Therefore Excluded from Computation of Diluted Net Loss Per Share	'
	The following table shows the total outstanding securities considered anti-dilutive, and therefore excluded from the computation of diluted net loss per share (in thousands):
		As of
		September 30,
		2013		2012
	Options to purchase common stock		9,778		11,025
	Restricted stock units		42		—
	Warrants to purchase common stock		169		650
	Total		9,989		11,675

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Summary of Stock Compensation Expense Related to Employee Stock Options and Employee Stock Based Compensation	'
	The following table summarizes stock compensation expense related to employee stock options and employee stock-based compensation for the three and nine months ended September 30, 2013 and 2012, which was incurred as follows (in thousands):
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
	Stock compensation expense:
	Product costs	$	7		$	3		$	17		$	8
	Research and development		38			19			92			50
	Sales and marketing		29			19			87			48
	General and administrative		119			52			236			151
	Total stock compensation expense	$	193		$	93		$	432		$	257
Weighted Average Assumptions Used with Regard to Stock Option	'
	The weighted average assumptions used were as follows:
		Three Months Ended						Nine Months Ended
		September 30,						September 30,
		2013			2012			2013			2012
	Dividend yield		0	%		0	%		0	%		0	%
	Risk-free interest rate		1.13	%		0.58	%		0.93	%		0.54	%
	Expected volatility		79.42	%		95.47	%		84.66	%		95.98	%
	Forfeiture rate		13.9	%		13.24	%		13.9	%		13.24	%
	Expected term (years)		4.06			4.12			4.06			4.12
	Fair value per share at grant date	$	0.75		$	0.22		$	0.61		$	0.21
Schedule of Stock Option Activity	'
	The table below presents information related to stock option activity for the nine months ended September 30, 2013, as follows:
		Number of			Weighted-			Weighted-			Aggregate
		Options			Average			Average			Intrinsic
		Outstanding			Exercise			Remaining			Value
					Price			Contractual
								Term
								(In years)
	Outstanding at December 31, 2012		8,963,226		$	0.47
	Options granted		1,563,910			1
	Options exercised		(611,596	)		0.26
	Options cancelled/forfeited/expired		(137,484	)		3.92
	Outstanding at September 30, 2013		9,778,056		$	0.52			8.15		$	13,734,086
	Exercisable at September 30, 2013		5,110,489		$	0.52			7.64		$	7,639,909
	Vested and expected to vest at September 30, 2013		9,031,664		$	0.52			8.1		$	12,784,188

Stock_Warrants_Tables

Stock Warrants (Tables)	9 Months Ended
	Sep. 30, 2013
Equity [Abstract]	'
Summarizes Information about All Warrants Outstanding	'
	The following table summarizes information about all warrants outstanding as of September 30, 2013:
		Warrants Outstanding and Exercisable
	Exercise Price	Number		Weighted		Weighted
		Outstanding		Average		Average
				Remaining		Exercise
				Contractual		Price
				Life (In Years)
	$0.37		168,919		5.95	$	0.37

Leases_Commitments_and_Conting1

Leases, Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Future Minimum Lease Payments under Non-Cancelable Operating Leases	'
	As of September 30, 2013, future minimum lease payments under non-cancelable operating leases are as follows (in thousands):
		Operating
		Leases
	2013 (remainder of year)	$	626
	2014		2,581
	2015		2,658
	2016		2,738
	Total minimum lease payments	$	8,603

Business_Overview_Additional_I

Business Overview - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Dec. 31, 2012
Schedule Of Description Of Business [Line Items]	'	'	'
Cumulative net loss	($199,702,000)	($199,702,000)	($197,732,000)
Excise tax as product revenue	89,000	303,000	'
Excise tax recognized in product costs	98,000	351,000	'
Maximum [Member]	'	'	'
Schedule Of Description Of Business [Line Items]	'	'	'
Liquidity ratio	'	1.25	'
Cumulative net loss	$6,000,000	$6,000,000	'
Minimum [Member]	'	'	'
Schedule Of Description Of Business [Line Items]	'	'	'
Liquidity ratio	'	1	'

Cash_Cash_Equivalents_and_Inve2

Cash, Cash Equivalents and Investments - Additional Information (Detail) (USD $)	9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013
Cash And Cash Equivalents [Abstract]	'
Maturity period of securities	'1 year
Maturity period for all highly liquid investments	'3 months
Notes payable face value	$5

Cash_Cash_Equivalents_and_Inve3

Cash, Cash Equivalents and Investments - Cash, Cash Equivalents, and Available-for-Sale Securities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Cash Cash Equivalents And Short Term Investments [Line Items]	'	'	'	'
Cash and cash equivalents, Cost Basis	$12,176	$12,851	$12,955	$10,484
Cash and cash equivalents, Unrealized Gains	'	'	'	'
Cash and cash equivalents, Unrealized Losses	'	'	'	'
Cash and cash equivalents, Estimated Fair Value	12,176	12,851	'	'
Available-for-sale securities, Cost Basis	'	747	'	'
Available-for-sale securities, Unrealized Gains	'	'	'	'
Available-for-sale securities, Unrealized Losses	'	'	'	'
Available-for-sale securities, Estimated Fair Value	'	747	'	'
Cash [Member]	'	'	'	'
Cash Cash Equivalents And Short Term Investments [Line Items]	'	'	'	'
Cash and cash equivalents, Cost Basis	8,129	6,054	'	'
Cash and cash equivalents, Unrealized Gains	'	'	'	'
Cash and cash equivalents, Unrealized Losses	'	'	'	'
Cash and cash equivalents, Estimated Fair Value	8,129	6,054	'	'
Money market funds [Member]	'	'	'	'
Cash Cash Equivalents And Short Term Investments [Line Items]	'	'	'	'
Cash and cash equivalents, Cost Basis	4,047	6,797	'	'
Cash and cash equivalents, Unrealized Gains	'	'	'	'
Cash and cash equivalents, Unrealized Losses	'	'	'	'
Cash and cash equivalents, Estimated Fair Value	4,047	6,797	'	'
Certificates of deposit [Member]	'	'	'	'
Cash Cash Equivalents And Short Term Investments [Line Items]	'	'	'	'
Available-for-sale securities, Cost Basis	'	747	'	'
Available-for-sale securities, Unrealized Gains	'	'	'	'
Available-for-sale securities, Unrealized Losses	'	'	'	'
Available-for-sale securities, Estimated Fair Value	'	$747	'	'

Cash_Cash_Equivalents_and_Inve4

Cash, Cash Equivalents and Investments - Fair Value Hierarchy for Financial Assets Measured at Fair Value on Recurring Basis (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	$13,576	$14,998
Restricted cash [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	1,400	1,400
Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	'	747
Cash [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	8,129	6,054
Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	4,047	6,797
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	12,176	12,851
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	8,129	6,054
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money market funds [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	4,047	6,797
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	1,400	2,147
Significant Other Observable Inputs (Level 2) [Member] | Restricted cash [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	1,400	1,400
Significant Other Observable Inputs (Level 2) [Member] | Certificates of deposit [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets, Fair Value Measurements	'	$747

Inventory_Inventory_Detail

Inventory - Inventory (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]	'	'
Finished goods	$428	$61
Raw materials	139	73
Total inventory	$567	$134

Assets_Held_For_Sale_Assets_He

Assets Held For Sale - Assets Held for Sale (Detail) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets held for sale	'	$300
Total Gains (Losses)	340	'
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets held for sale	'	'
Significant Other Observable Inputs (Level 2) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets held for sale	'	'
Significant Unobservable Inputs (Level 3) [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets held for sale	'	300
Carrying Value [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'	'
Assets held for sale	'	'

Assets_Held_For_Sale_Additiona

Assets Held For Sale - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Property Plant And Equipment Assets Held For Sale Disclosure [Abstract]	'	'	'	'
Committed sales price for assets held for sale	'	'	'	$695,000
Gains (losses) on sale of assets	($7,000)	$340,000	($4,000)	'

Property_Plant_and_Equipment_S

Property, Plant and Equipment - Schedule of Estimated Useful Lives for Significant Property and Equipment (Detail)	9 Months Ended
	Sep. 30, 2013
Office and laboratory equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives	'3 years
Computer equipment and software [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives	'3 years
Leasehold improvements [Member]	'
Property, Plant and Equipment [Line Items]	'
Leasehold improvements	'Term of lease agreement

Property_Plant_and_Equipment_P

Property, Plant and Equipment - Property and Equipment at Cost Less Accumulated Depreciation (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	$4,448	$4,292
Less: Accumulated depreciation and amortization	-3,443	-3,042
Total Property, Plant and Equipment	1,005	1,250
Laboratory equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	3,207	3,149
Leasehold improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	602	602
Computer equipment and software [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	375	361
Furniture and fixtures [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	181	180
Construction in progress [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Gross property and equipment	$83	'

Property_Plant_and_Equipment_A

Property, Plant and Equipment - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Property Plant And Equipment [Abstract]	'	'	'	'
Depreciation and amortization expense	$0.10	$0.10	$0.40	$0.40

Total_Accrued_and_Other_Curren2

Total Accrued and Other Current Liabilities - Accrued and Other Current Liabilities (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Payables And Accruals [Abstract]	'	'
Accrued payroll and related expenses	$1,252	$1,220
Accrued inventory	323	'
Accrued consulting expense	143	122
Accrued collaborative research obligations	82	22
Accrued sales and excise tax	82	60
Accrued audit fees	77	73
Accrued royalty expenses	62	118
Accrued legal and patent expense	46	87
Accrued property and equipment	'	27
Other current liabilities	263	224
Total accrued and other current liabilities	$2,330	$1,953

Concentration_of_Credit_Risk_R

Concentration of Credit Risk - Revenues from Large Laboratory Customers (Detail)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	85.00%	78.00%	82.00%	76.00%	'
Accounts Receivable	89.00%	'	89.00%	'	73.00%
Customer A [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	43.00%	44.00%	44.00%	45.00%	'
Accounts Receivable	40.00%	'	40.00%	'	34.00%
Customer B [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	14.00%	15.00%	13.00%	13.00%	'
Accounts Receivable	10.00%	'	10.00%	'	14.00%
Customer C [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	10.00%	6.00%	9.00%	6.00%	'
Accounts Receivable	2.00%	'	2.00%	'	2.00%
Customer D [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	8.00%	1.00%	5.00%	2.00%	'
Accounts Receivable	21.00%	'	21.00%	'	3.00%
Customer E [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	6.00%	6.00%	6.00%	6.00%	'
Accounts Receivable	10.00%	'	10.00%	'	10.00%
Customer F [Member]	'	'	'	'	'
Concentration Risk [Line Items]	'	'	'	'	'
Revenue	4.00%	6.00%	5.00%	4.00%	'
Accounts Receivable	6.00%	'	6.00%	'	10.00%

Notes_Payable_Additional_Infor

Notes Payable - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2013
		Installment
Debt Instrument [Line Items]	'	'
Period for monthly installment	'	'Monthly
Debt instrument number of installments	'	36
Loan processing fee	'	$25,000
Additional fee required	'	100,000
Advance notice period to the bank	'	'30 days
Warrant issued to purchase common stock	480,769	'
Exercise price of warrants	$0.26	'
Warrant expiry date	'2013-08	'2013-08
Monthly revenue projections	'	80.00%
Repayment of term loan description	'	'The repayment of the term loan may be accelerated, at the option of the bank, following the occurrence of an event of default, which would require the Company to pay to the bank an amount equal to the sum of: (i) all outstanding principal plus accrued interest, (ii) the final payment, and (iii) all other sums that shall have become due and payable but have not been paid, including interest at the default rate with respect to any past due amounts. As of September 30, 2013, the Company was in compliance with all the covenants.
First Amended Loan And Security Agreement [Member]	'	'
Debt Instrument [Line Items]	'	'
Amended and Restated Loan and Security, Maturity date	'	23-Sep-16
Extended interest-only payment period	'	23-Sep-13
Monthly principal payments by amortizing the loan	'	'48 months
Amendment access fee	'	50,000
Common stock purchase	'	168,919
Warrants exercise price per share	'	$0.37
Warrant expiry date	'	11-Sep-19
Present value of modified debt instrument	'	10.00%
Debt discount	'	48,000
Unamortized debt discount	'	72,000
Notes payable [Member]	'	'
Debt Instrument [Line Items]	'	'
Proceeds from bank debt	5,000,000	'
Interest rate on loan	5.25%	'
Unamortized debt discount	'	$77,000

Notes_Payable_Future_Minimum_P

Notes Payable - Future Minimum Payments for Notes Payable (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Standby Letters of Credit [Line Items]	'	'
Less: Notes payable, current portion	($1,214,000)	($272,000)
Non-current portion of notes payable	3,709,000	4,621,000
Notes payable [Member]	'	'
Standby Letters of Credit [Line Items]	'	'
2013 (remainder of year)	377,000	'
2014	1,466,000	'
2015	1,400,000	'
2016	2,357,000	'
Total minimum payments	5,600,000	'
Less: Amount representing interest	-600,000	'
Present value of minimum payments	5,000,000	'
Less: Unamortized debt discount	-77,000	'
Notes payable, net	4,923,000	'
Less: Notes payable, current portion	-1,214,000	'
Non-current portion of notes payable	$3,709,000	'

Common_Stock_Additional_Inform

Common Stock - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Jul. 15, 2011
Equity [Abstract]	'	'	'
Common stock, shares authorized	100,000,000	100,000,000	100,000,000
Increase in number of authorized shares of common stock, par value	$0.01	$0.01	$0.01

Basic_and_Diluted_Net_Loss_per2

Basic and Diluted Net Loss per Share - Outstanding Securities Considered Anti-Dilutive, and Therefore Excluded from Computation of Diluted Net Loss Per Share (Detail)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total	9,989	11,675
Options to purchase common stock [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total	9,778	11,025
Restricted stock units [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total	42	'
Warrants to purchase common stock [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total	169	650

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)

9 Months Ended

1 Months Ended

9 Months Ended

9 Months Ended

9 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

1 Months Ended

In Millions, except Share data, unless otherwise specified

Sep. 30, 2013

Dec. 31, 2012

Aug. 06, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

17-May-12

Sep. 30, 2013

Sep. 30, 2013

17-May-12

Sep. 30, 2013

Oct. 31, 2004

Sep. 30, 2013

Sep. 30, 2011

Sep. 30, 2013

Oct. 31, 2011

Sep. 30, 2013

Feb. 29, 2012

Sep. 30, 2013

Feb. 01, 2012

Restricted Stock Units (RSUs) [Member]

Restricted Stock Units (RSUs) [Member]

2012 Equity Incentive Award Plan [Member]

2012 Equity Incentive Award Plan [Member]

1996 Stock Option Plan [Member]

1996 Stock Option Plan [Member]

1996 Stock Option Plan [Member]

1998 Director Stock Option Plan [Member]

1998 Director Stock Option Plan [Member]

1998 Director Stock Option Plan [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Non-Plan Grants [Member]

Director [Member]

Director [Member]

Options to purchase common stock [Member]

Options to purchase common stock [Member]

Options to purchase common stock [Member]

Director [Member]

Director [Member]

Chief Executive Officer [Member]

Chief Executive Officer [Member]

Chief Business Officer [Member]

Chief Business Officer [Member]

Chief Financial Officer [Member]

Chief Financial Officer [Member]

Chief Financial Officer [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares of common stock authorized for issuance

'

'

'

'

'

3,000,000

'

'

4,750,000

'

'

300,000

'

'

'

'

'

'

'

'

'

Issuable upon exercise of options vest

'

'

'

'

'4 years

'

'

'

'4 years

'

'

'

'

'

'

'

'

'

'

'

'

Non Employee Stock Options Vesting Period

'1 year

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Options outstanding

9,778,056

8,963,226

'

'

3,031,850

'

3,050,288

6,398,904

'

60,000

170,000

'

'

30,000

'

1,530,000

'

1,018,458

'

1,057,460

'

Shares available for grant

'

'

'

'

2,325,617

'

'

'

'

'

'

'

30,000

'

1,530,000

'

1,130,000

'

'

'

1,060,000

Condition for stock option expiry

'Option terms expire no later than 10 years from the date of grant, or 5 years from the date the option is granted to a greater than 10% stockholder

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Condition for stock options exercisable

'Stock options are exercisable at not less than the fair market value of the stock at the date of grant, or not less than 110% of the fair market value of the stock at the date of grant if granted to a greater than 10% stockholder

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Percentage increased by the number of issued and outstanding common stock

'

'

'

'

'

'

'

'

3.50%

'

'

'

'

'

'

'

'

'

'

'

'

Options expire from the date of grant

'

'

'

'

'

'

'

'

'10 years

'

'

'

'

'

'

'

'

'

'

'

'

Period between grant date and vesting period start date

'

'

'

'

'

'

'

'

'1 year

'

'

'

'

'

'

'

'

'

'

'

'

Determination of Non qualified stock options exercise price fair market value of stock minimum percentage

'

'

'

'

'

'

85.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares transferred form prior plans available for issuance under the plan

'

'

'

'

'

'

'

1,555,492

'

'

130,000

'

'

'

'

'

'

'

'

'

'

Stock option plans, exercise price per share

$0.26

'

'

'

'

'

'

'

'

'

'

'

$12.27

'

$0.25

'

$0.26

'

$0.28

'

'

Restricted Stock Units awarded to directors

'

'

41,708

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted Stock Units, grant-date fair value

'

'

55,472

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted Stock Units awarded, outstanding

'

'

'

41,708

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

RSU entitles the recipient to receive share of the Company's common stock upon vesting

'

'

'

1

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total remaining unrecognized cost for stock-based compensation

$1.10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock-based compensation expenses recognition period

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

StockBased_Compensation_Summar

Stock-Based Compensation - Summary of Stock Compensation Expense Related to Employee Stock Options and Employee Stock Based Compensation (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Stock compensation expense:	'	'	'	'
Total stock compensation expense	$193	$93	$432	$257
Product costs [Member]	'	'	'	'
Stock compensation expense:	'	'	'	'
Total stock compensation expense	7	3	17	8
Research and development [Member]	'	'	'	'
Stock compensation expense:	'	'	'	'
Total stock compensation expense	38	19	92	50
Sales and marketing [Member]	'	'	'	'
Stock compensation expense:	'	'	'	'
Total stock compensation expense	29	19	87	48
General and administrative [Member]	'	'	'	'
Stock compensation expense:	'	'	'	'
Total stock compensation expense	$119	$52	$236	$151

StockBased_Compensation_Weight

Stock-Based Compensation - Weighted Average Assumptions Used with Regard to Stock Option (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'	'	'	'	'
Dividend yield	'	0.00%	0.00%	0.00%	0.00%
Risk-free interest rate	1.36%	1.13%	0.58%	0.93%	0.54%
Expected volatility	'	79.42%	95.47%	84.66%	95.98%
Forfeiture rate	'	13.90%	13.24%	13.90%	13.24%
Expected term (years)	'	'4 years 22 days	'4 years 1 month 13 days	'4 years 22 days	'4 years 1 month 13 days
Fair value per share at grant date	'	$0.75	$0.22	$0.61	$0.21

StockBased_Compensation_Schedu

Stock-Based Compensation - Schedule of Stock Option Activity (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Number of Options Outstanding, Beginning balance	8,963,226
Number of Options Outstanding, Options granted	1,563,910
Number of Options Outstanding, Options exercised	-611,596
Number of Options Outstanding, Options cancelled/forfeited/expired	-137,484
Number of Options Outstanding, Ending balance	9,778,056
Number of Options Outstanding, Exercisable, Ending balance	5,110,489
Number of Options Outstanding, Vested and expected to vest, Ending balance	9,031,664
Weighted-Average Exercise Price, Outstanding Beginning balance	$0.47
Weighted-Average Exercise Price, Options granted	$1
Weighted-Average Exercise Price, Options exercised	$0.26
Weighted-Average Exercise Price, Options cancelled/forfeited/expired	$3.92
Weighted-Average Exercise Price, Outstanding Ending balance	$0.52
Weighted-Average Exercise Price, Exercisable, Ending balance	$0.52
Weighted-Average Exercise Price, Vested and expected to vest, Ending balance	$0.52
Weighted- Average Remaining Contractual Term, Outstanding, Ending balance	'8 years 1 month 24 days
Weighted- Average Remaining Contractual Term, Exercisable, Ending balance	'7 years 7 months 21 days
Weighted- Average Remaining Contractual Term, Vested and expected to vest, Ending balance	'8 years 1 month 6 days
Aggregate Intrinsic Value, Outstanding, Ending balance	$13,734,086
Aggregate Intrinsic Value, Exercisable, Ending balance	7,639,909
Aggregate Intrinsic Value, Vested and expected to vest, Ending balance	$12,784,188

Stock_Warrants_Additional_Info

Stock Warrants - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended			1 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2011	Sep. 30, 2013	Aug. 31, 2013	Sep. 30, 2013
							Warrants outstanding [Member]	Warrants outstanding [Member]	Warrants to purchase common stock [Member]	Warrants to purchase common stock [Member]
Class of Warrant or Right [Line Items]	'	'	'	'	'	'	'	'	'	'
Warrant issued to purchase common stock	480,769	'	'	'	'	'	'	'	'	168,919
Exercise price of warrant	$0.26	'	'	'	'	'	'	'	$0.26	$0.37
Volatility	'	79.42%	95.47%	84.66%	95.98%	'	88.03%	'	'	89.87%
Risk-free interest rate	1.36%	1.13%	0.58%	0.93%	0.54%	'	'	'	'	1.03%
Expected life of warrant	'7 years	'	'	'	'	'	'	'	'	'7 years
Fair value of warrant	$94,000	'	'	'	'	'	'	'	'	$48,000
Discount being amortized to interest expense	'	'	'	'	'	'	'	'48 months	'	'
Warrant expiry date	'2013-08	'	'	'2013-08	'	'	'	'	'	'
Common stock, shares issued	'	54,698,713	'	54,698,713	'	53,890,314	'	'	386,784	'
Common stock pursuant to cashless exercise of warrant	'	'	'	'	'	'	'	'	480,769	'
Number of shares purchased against warrants outstanding	'	'	'	'	'	'	'	168,919	'	'
Exercise price of warrants outstanding	'	'	'	'	'	'	'	0.37	'	'
Aggregate exercise price	'	'	'	'	'	'	'	$63,000	'	'

Stock_Warrants_Summarizes_Info

Stock Warrants - Summarizes Information about All Warrants Outstanding (Detail) (Warrant 0.37 [Member])	9 Months Ended
	Sep. 30, 2013
Warrant 0.37 [Member]	'
Class of Warrant or Right [Line Items]	'
Warrants Outstanding and Exercisable, Number	168,919
Warrants Outstanding and Exercisable, Weighted Average Remaining Contractual Life (In Years)	'5 years 11 months 12 days
Warrants Outstanding and Exercisable, Weighted Average Exercise Price	0.37

Leases_Commitments_and_Conting2

Leases, Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2010
	Facility		Facility
Commitments And Contingencies Disclosure [Abstract]	'	'	'	'	'	'
Number of facility	349	'	349	'	'	'
Lease expiration date	'	'	'2016-12	'	'	'
Unfavorable lease obligation expense	'	'	'	'	'	$4,100,000
Rent expense	484,000	508,000	1,500,000	1,500,000	'	'
Deferred rent	$381,000	'	$381,000	'	$363,000	'

Leases_Commitments_and_Conting3

Leases, Commitments and Contingencies - Future Minimum Lease Payments under Non-Cancelable Operating Leases (Detail) (USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified
Commitments And Contingencies Disclosure [Abstract]	'
2013 (remainder of year)	$626
2014	2,581
2015	2,658
2016	2,738
Total minimum lease payments	$8,603

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2013
Income Tax Disclosure [Abstract]	'	'
Effective tax rate	0.00%	0.00%
Expected effective tax rate current year	'	0.00%
Unrecognized tax benefits	$1,600,000	$1,600,000
Expected material changes in the next 12 months in unrecognized tax benefits	'	0
Accrued interest and penalties related to uncertain tax positions	$0	$0

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013	Sep. 30, 2013	Oct. 31, 2013	Oct. 31, 2013	Oct. 31, 2013
			Maximum [Member]	Minimum [Member]	Second Amended Loan and Security Agreement [Member]	Second Amended Loan and Security Agreement [Member]	Second Amended Loan and Security Agreement [Member]
			Ratio	Ratio	Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]
						Maximum [Member]	Minimum [Member]
						Ratio	Ratio
Subsequent Event [Line Items]	'	'	'	'	'	'	'
Increase in aggregate principal amount of loan	'	'	'	'	$5,000,000	'	'
Total outstanding principal amount	'	'	'	'	10,000,000	'	'
Interest rate on loan	'	'	'	'	6.45%	'	'
Amended and Restated Loan and Security, Maturity date	'	'	'	'	1-Dec-16	'	'
Extends interest-only payment period	'	'	'	'	31-Dec-13	'	'
Monthly principal payments by amortizing the loan	'	'	'	'	'42 months	'	'
Liquidity ratio	'	'	1.25	1	'	1.25	1
Cumulative net loss	-199,702,000	-197,732,000	6,000,000	'	'	6,000,000	'
Amendment access fee	'	'	'	'	$50,000	'	'
Common stock purchase	'	'	'	'	96,685	'	'
Warrants exercise price per share	'	'	'	'	$1.81	'	'
Warrant expiry date	'	'	'	'	17-Oct-20	'	'