Cerus (CERS) 10-Q 12 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 24, 2014
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'CERS	'
Entity Registrant Name	'CERUS CORP	'
Entity Central Index Key	'0001020214	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	72,513,000

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$23,992	$29,485	[1]
Short-term investments	24,263	28,191	[1]
Accounts receivable	4,943	6,125	[1]
Inventories	11,307	13,063	[1]
Prepaid expenses	1,661	848	[1]
Other current assets	913	442	[1]
Total current assets	67,079	78,154	[1]
Non-current assets:	'	'
Property and equipment, net	3,166	2,189	[1]
Goodwill	1,316	1,316	[1]
Intangible assets, net	1,294	1,344	[1]
Restricted cash	308	308	[1]
Other assets	64	70	[1]
Total assets	73,227	83,381	[1]
Current liabilities:	'	'
Accounts payable	3,493	5,674	[1]
Accrued liabilities	8,838	9,813	[1]
Deferred revenue	279	181	[1]
Debt - current	3,268	3,366	[1]
Warrant liability	11,356	20,390	[1]
Total current liabilities	27,234	39,424	[1]
Non-current liabilities:	'	'
Deferred income taxes	95	89	[1]
Other non-current liabilities	1,031	1,073	[1]
Total liabilities	28,360	40,586	[1]
Commitments and contingencies	'	'	[1]
Stockholders' equity:	'	'
Common stock	72	72	[1]
Additional paid-in capital	548,202	545,905	[1]
Accumulated other comprehensive income	7	7	[1]
Accumulated deficit	-503,414	-503,189	[1]
Total stockholders' equity	44,867	42,795	[1]
Total liabilities and stockholders' equity	$73,227	$83,381	[1]
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenue:	'	'
Product revenue	$7,866	$9,733
Cost of product revenue	4,157	5,090
Gross profit on product revenue	3,709	4,643
Operating expenses:	'	'
Research and development	4,642	2,700
Selling, general and administrative	8,236	6,853
Amortization of intangible assets	50	50
Total operating expenses	12,928	9,603
Loss from operations	-9,219	-4,960
Non-operating gain (expense), net:	'	'
Gain (loss) from revaluation of warrant liability	9,034	-5,073
Foreign exchange gain (loss)	21	-54
Interest expense	-193	-131
Other income, net	170	17
Total non-operating gain (expense), net	9,032	-5,241
Loss before income taxes	-187	-10,201
Provision for income taxes	38	51
Net loss	($225)	($10,252)
Net loss per share:	'	'
Basic	$0	($0.17)
Diluted	($0.12)	($0.17)
Weighted average shares outstanding used for calculating net loss per share:	'	'
Basic	72,088	59,730
Diluted	75,158	59,730

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net loss	($225)	($10,252)
Other comprehensive loss	0	0
Comprehensive loss	($225)	($10,252)

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Operating activities	'		'
Net loss	($225)		($10,252)
Adjustments to reconcile net loss to net cash used in operating activities:	'		'
Depreciation and amortization	325		167
Stock-based compensation	946		713
Changes in revaluation of warrant liability	-9,034		5,073
Non-cash interest expense	0		4
Deferred income taxes	6		7
Loss on disposal of fixed assets	0		56
Changes in operating assets and liabilities, net of effects of acquired business:	'		'
Accounts receivable	1,182		-289
Inventories	1,117		-1,624
Other assets	-764		910
Accounts payable	-2,181		-3,299
Accrued liabilities	-1,295		85
Deferred revenue	98		97
Net cash used in operating activities	-9,825		-8,352
Investing activities	'		'
Capital expenditures	-839		-26
Purchases of investments and certain other assets	-460		0
Maturities of investments	4,300		0
Net cash provided by (used in) investing activities	3,001		-26
Financing activities	'		'
Net proceeds from equity incentive plans	1,425		152
Net proceeds from public offering	31		51,502
Proceeds from revolving line of credit	0		526
Payments on debt, revolving line of credit and landlord provided leasehold incentives	-125		-1,335
Net cash provided by financing activities	1,331		50,845
Net increase in cash and cash equivalents	-5,493		42,467
Cash and cash equivalents, beginning of period	29,485	[1]	26,696
Cash and cash equivalents, end of period	$23,992		$69,163
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Summary of Significant Accounting Policies	'
	Note 1. Summary of Significant Accounting Policies
	Principles of Consolidation and Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements include those of Cerus Corporation and its subsidiary, Cerus Europe B.V. (collectively referred to hereinafter as “Cerus” or the “Company”) after elimination of all intercompany accounts and transactions. These condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring entries, considered necessary for a fair presentation have been made. Operating results for the three months ended March 31, 2014, are not necessarily indicative of the results that may be expected for the year ending December 31, 2014, or for any future periods.
	These condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto for the year ended December 31, 2013, which were included in the Company’s 2013 Annual Report on Form 10-K, filed with the SEC on March 7, 2014. The accompanying consolidated balance sheet as of December 31, 2013 has been derived from the Company’s audited consolidated financial statements as of that date.
	Use of Estimates
	The preparation of financial statements requires management to make estimates, assumptions and judgments that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures of contingent assets and liabilities. On an ongoing basis, management evaluates its estimates, which are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions.
	Revenue
	The Company recognizes revenue in accordance with ASC Topic 605-25, “Revenue Recognition – Arrangements with Multiple Deliverables,” as applicable. Revenue is recognized when (i) persuasive evidence of an agreement with the funding party exists; (ii) services have been rendered or product has been delivered; (iii) pricing is fixed or determinable; and (iv) collection is reasonably assured. The Company’s source of revenues for the three months ended March 31, 2014 and 2013 was product revenue from sales of the INTERCEPT Blood System for platelets and plasma (“platelet and plasma systems”).
	Revenue related to product sales is generally recognized when the Company fulfills its obligations for each element of an agreement. For all sales of the Company’s INTERCEPT Blood System products, the Company uses a binding purchase order and signed sales contract as evidence of a written agreement. The Company sells its platelet and plasma systems directly to blood banks, hospitals, universities, government agencies, as well as to distributors in certain regions. Generally, the Company’s contracts with its customers do not provide for open return rights, except within a reasonable time after receipt of goods in the case of defective or non-conforming product. Deliverables and the units of accounting vary according to the provisions of each purchase order or sales contract. For revenue arrangements with multiple elements, the Company determines whether the delivered elements meet the criteria as separate units of accounting. Such criteria require that the deliverable have stand-alone value to the customer and that if a general right of return exists relative to the delivered item, delivery or performance of the undelivered item(s) is considered probable and substantially in the control of the Company. Once the Company determines if the deliverable meets the criteria for a separate unit of accounting, the Company must determine how the consideration should be allocated between the deliverables and how the separate units of accounting should be recognized as revenue. Consideration received is allocated to elements that are identified as discrete units of accounting based on the best estimated selling price. The Company has determined that vendor specific objective evidence is not discernible due to the Company’s variability in its pricing across the regions into which it sells its products. Since the Company’s products are novel and unique and are not sold by others, third-party evidence of selling price is unavailable.
	At March 31, 2014 and December 31, 2013, the Company had $0.3 million and $0.2 million, respectively, of short-term deferred revenue on its condensed consolidated balance sheets related to future performance obligations. Freight costs charged to customers are recorded as a component of revenue under ASC Topic 605, “Accounting for Shipping and Handling Fees and Costs.” Value-added-taxes (“VAT”) that the Company invoices to its customers and remits to governments are recorded on a net basis, which excludes such VAT from product revenue.
	Research and Development Expenses
	In accordance with ASC Topic 730, “Accounting for Research and Development Expenses,” research and development expenses are charged to expense when incurred. Research and development expenses include salaries and related expenses for scientific personnel, payments to consultants, supplies and chemicals used in in-house laboratories, costs of research and development facilities, depreciation of equipment and external contract research expenses, including clinical trials, preclinical safety studies, other laboratory studies, process development and product manufacturing for research use.
	The Company’s use of estimates in recording accrued liabilities for research and development activities (see “Use of Estimates” above) affects the amounts of research and development expenses recorded and revenue recorded from development funding and government grants and collaborative agreements. Actual results may differ from those estimates under different assumptions or conditions.
	Cash Equivalents
	The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be classified as cash equivalents. These investments primarily consist of money market instruments, and are classified as available-for-sale.
	Short-Term Investments
	Investments with original maturities of greater than three months which included corporate debt and United States government agency securities are designated as available-for-sale and classified as short-term investments. In accordance with ASC Topic 320, “Accounting for Certain Investments in Debt and Equity Securities,” the Company classified all debt securities as available-for-sale at the time of purchase and reevaluates such designation as of each balance sheet date. Available-for-sale securities are carried at estimated fair value. Unrealized gains and losses derived by changes in the estimated fair value of available-for-sale securities were recorded in “Net unrealized gains (losses) on available-for-sale securities, net of taxes” on the Company’s condensed consolidated statements of comprehensive loss. Realized gains and losses from the sale of available-for-sale investments were recorded in “Other income, net” on the Company’s condensed consolidated statements of operations. The cost of securities sold was based on the specific identification method. The Company reported the amortization of any premium and accretion of any discount resulting from the purchase of debt securities as a component of interest income.
	The Company also reviews its marketable securities on a regular basis to evaluate whether any security has experienced an other-than-temporary decline in fair value. Other-than-temporary declines in market value are recorded in “Other income (expense), net” on the Company’s condensed consolidated statements of operations.
	Restricted Cash
	The Company holds a certificate of deposit with a domestic bank for any potential decommissioning resulting from the Company’s possession of radioactive material. The certificate of deposit is held to satisfy the financial surety requirements of the California Department of Health Services and is recorded in “Restricted cash” on the Company’s condensed consolidated balance sheets. The Company also has certain non-US dollar denominated deposits recorded as “Restricted cash” in compliance with certain foreign contractual requirements.
	Concentration of Credit Risk
	Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash equivalents, short-term investments and accounts receivable.
	Pursuant to the Company’s investment policy, substantially all of the Company’s cash, cash equivalents and short-term investments are maintained at major financial institutions of high credit standing. The Company monitors the financial credit worthiness of the issuers of its investments and limits the concentration in individual securities and types of investments that exist within its investment portfolio. Generally, all of the Company’s investments carry high credit quality ratings, which is in accordance with its investment policy. At March 31, 2014, the Company does not believe there is significant financial risk from non-performance by the issuers of the Company’s cash equivalents.
	Concentrations of credit risk with respect to trade receivables exist. However, in connection with the Company’s revolving line of credit, as discussed in Note 8 in the Notes to Condensed Consolidated Financial Statements, the Company purchased a credit insurance policy that mitigates some of its credit risk, as the policy will pay either the Company or its lender on eligible claims filed on its outstanding receivables. On a regular basis, including at the time of sale, the Company performs credit evaluations of its customers. Generally, the Company does not require collateral from its customers to secure accounts receivable. To the extent that the Company determines specific invoices or customer accounts may be uncollectible, the Company reserves against the accounts receivable on its condensed consolidated balance sheets and records a charge on its condensed consolidated statements of operations. At March 31, 2014 and December 31, 2013, the Company had not recorded any reserves for potentially uncollectible accounts.
	The Company had three customers and two customers that accounted for more than 10% of the Company’s outstanding trade receivables at March 31, 2014, and December 31, 2013, respectively. These customers cumulatively represented approximately 65% and 55% of the Company’s outstanding trade receivables at March 31, 2014, and December 31, 2013, respectively. To date, the Company has not experienced collection difficulties from these customers.
	Inventories
	At March 31, 2014, and December 31, 2013, inventory consisted of work-in-process and finished goods only. Finished goods include INTERCEPT disposable kits, UVA illumination devices (“illuminators”), and certain replacement parts for the illuminators. Platelet and plasma systems’ disposable kits generally have a two-year life from the date of manufacture. Illuminators and replacement parts do not have regulated expiration dates. Work-in-process includes certain components that are manufactured over a protracted length of time before being sold to and ultimately incorporated and assembled by Fresenius, Inc. (“Fresenius”) into the finished INTERCEPT disposable kits. The Company maintains an inventory balance based on its current sales projections, and at each reporting period, the Company evaluates whether its work-in-process inventory would be sold to Fresenius for production of finished units in order to sell to existing and prospective customers within the next twelve-month period. It is not customary for the Company’s production cycle for inventory to exceed twelve months. Instead, the Company uses its best judgment to factor in lead times for the production of its work-in-process and finished units to meet the Company’s forecasted demands. If actual results differ from those estimates, work-in-process inventory could potentially accumulate for periods exceeding one year. At March 31, 2014 and December 31, 2013, the Company classified its work-in-process inventory as a current asset on its condensed consolidated balance sheets based on its evaluation that the work-in-process inventory would be sold to Fresenius for finished disposable kit production within each respective subsequent twelve-month period.
	Inventory is recorded at the lower of cost, determined on a first-in, first-out basis, or market value. The Company uses significant judgment to analyze and determine if the composition of its inventory is obsolete, slow-moving or unsalable and frequently reviews such determinations. The Company writes-down specifically identified unusable, obsolete, slow-moving, or known unsalable inventory that has no alternative use in the period that it is first recognized by using a number of factors including product expiration dates, open and unfulfilled orders, and sales forecasts. Any write-down of its inventory to net realizable value establishes a new cost basis and will be maintained even if certain circumstances suggest that the inventory is recoverable in subsequent periods. Costs associated with the write-down of inventory are recorded in “Cost of product revenue” on the Company’s condensed consolidated statements of operations. At March 31, 2014, and December 31, 2013, the Company had $0.3 million and $0.4 million, respectively, recorded for potential obsolete, expiring or unsalable product.
	Property and Equipment, net
	Property and equipment is comprised of furniture, equipment, leasehold improvements, information technology hardware and software and is recorded at cost. At the time the property and equipment is ready for its intended use, it is depreciated on a straight-line basis over the estimated useful lives of the assets (generally three to five years). Leasehold improvements are amortized on a straight-line basis over the shorter of the lease term or the estimated useful lives of the improvements.
	Capitalization of Software Costs
	The Company capitalizes certain significant costs incurred in the acquisition and development of software for internal use, including the costs of the software, materials, consultants, and payroll and payroll-related costs for employees during the application development stage. Costs incurred prior to the application development stage, costs incurred once the application is substantially complete and ready for its intended use, and other costs not qualifying for capitalization, including training and maintenance costs, are charged to expense.
	Goodwill and Intangible Assets, net
	Additions to goodwill and intangible assets, net are derived at the time of a business acquisition, in which the Company assigns the total consideration transferred to the acquired assets based on each asset’s fair value and any residual amount becomes goodwill, an indefinite life intangible asset. Intangible assets, net, which include a license for the right to commercialize the INTERCEPT Blood System in Asia, are subject to ratable amortization over the estimated useful life of ten years. The amortization of the Company’s intangible assets, net, is recorded in “Amortization of intangible assets” on the Company’s condensed consolidated statements of operations. Goodwill is not amortized but instead is subject to an impairment test performed on an annual basis, or more frequently if events or changes in circumstances indicate that goodwill may be impaired. Such impairment analysis is performed on August 31 of each fiscal year, or more frequently if indicators of impairment exist. The test for goodwill impairment may be assessed using qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than the carrying amount. If the Company determines that it is more likely than not that the fair value of a reporting unit is less than the carrying amount, the Company must then proceed with performing the quantitative two-step process to test goodwill for impairment; otherwise, goodwill is not considered impaired and no further testing is warranted. The Company may choose not to perform the qualitative assessment to test goodwill for impairment and proceed directly to the quantitative two-step process; however, the Company may revert to the qualitative assessment to test goodwill for impairment in any subsequent period. The first step of the two-step process compares the fair value of each reporting unit with its respective carrying amount, including goodwill. The Company has determined that it operates in one segment and has one reporting unit and estimates the fair value of its one reporting unit using the enterprise approach under which it considers the quoted market capitalization of the Company as reported on the Nasdaq Global Market. The Company considers quoted market prices that are available in active markets to be the best evidence of fair value. The Company also considers other factors, which include future forecasted results, the economic environment and overall market conditions. If the fair value of the reporting unit exceeds its carrying amount, goodwill of the reporting unit is not considered impaired and, therefore, the second step of the impairment test is unnecessary. The second step of the two-step process, which is used to measure the amount of impairment loss, compares the implied fair value of each reporting unit’s goodwill with the respective carrying amount of that goodwill. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized in an amount equal to that excess.
	The Company performs an impairment test on its intangible assets, in accordance ASC Topic 360-10, “Property, Plant and Equipment,” if certain events or changes in circumstances occur which indicate that the carrying amounts of its intangible assets may not be recoverable. If the intangible assets are not recoverable, an impairment loss would be recognized by the Company based on the excess amount of the carrying value of the intangible assets over its fair value. For further details regarding the impairment analysis, reference is made to the section below under “Long-lived Assets.” Also, see Note 5 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s impairment analysis and the valuation of goodwill and intangible assets, net.
	Long-lived Assets
	The Company evaluates its long-lived assets for impairment by continually monitoring events and changes in circumstances that could indicate carrying amounts of its long-lived assets may not be recoverable. When such events or changes in circumstances occur, the Company assesses recoverability by determining whether the carrying value of such assets will be recovered through the undiscounted expected future cash flows. If the expected undiscounted future cash flows are less than the carrying amount of these assets, the Company then measures the amount of the impairment loss based on the excess of the carrying amount over the fair value of the assets. The Company did not recognize impairment charges related to its long-lived assets during the three months ended March 31, 2014, and 2013.
	Foreign Currency Remeasurement
	The functional currency of the Company’s foreign subsidiary is the United States dollar. Monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using the exchange rates at the balance sheet date. Non-monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using historical exchange rates. Revenues and expenses are remeasured using average exchange rates prevailing during the period. Remeasurements are recorded in the Company’s condensed consolidated statements of operations. The Company recorded foreign currency gains (losses) of less than $0.1 million and $(0.1) million during the three months ended March 31, 2014, and 2013, respectively.
	Stock-Based Compensation
	The Company accounts for stock-based compensation in accordance with ASC Topic 718, “Compensation – Stock Compensation.” Stock-based compensation expense is measured at the grant-date based on the fair value of the award and is recognized as expense on a straight-line basis over the requisite service period, which is the vesting period, and is adjusted for estimated forfeitures. To the extent that stock options contain performance criteria for vesting, stock-based compensation is recognized once the performance criteria are probable of being achieved.
	For stock-based awards issued to non-employees, the Company follows ASC Topic 505-50, “Equity Based Payment to Non-Employees” and considers the measurement date at which the fair value of the stock-based award is measured to be the earlier of (i) the date at which a commitment for performance by the grantee to earn the equity instrument is reached or (ii) the date at which the grantee’s performance is complete. The Company recognizes stock-based compensation expense for the fair value of the vested portion of the non-employee stock-based awards in its condensed consolidated statements of operations.
	See Note 11 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s stock-based compensation assumptions and expenses.
	Warrant Liability
	In August 2009 and November 2010, the Company issued warrants to purchase an aggregate of 2.4 million and 3.7 million shares of common stock, respectively. The material terms of the warrants were identical under each issuance except for the exercise price, date issued and expiration date. The Company classifies the warrants as a liability on its condensed consolidated balance sheets as the warrants contain certain material terms which require the Company (or its successor) to purchase the warrants for cash in an amount equal to the value of the unexercised portion of the warrants (as determined in accordance with the Black-Scholes option pricing model) in connection with certain change of control transactions. In addition, the Company may also be required to pay cash to a warrant holder under certain circumstances if the Company is unable to timely deliver the shares acquired upon warrant exercise to such holder.
	The fair value of these outstanding warrants is calculated using the binomial-lattice option-pricing model and is adjusted accordingly at each reporting period. The binomial-lattice option-pricing model requires that the Company uses significant assumptions and judgment to determine appropriate inputs to the model. Some of the assumptions that the Company relies on include the probability of a change of control occurring, the volatility of the Company’s stock over the life of the warrant and assumptions and inputs used to value the warrants under the Black-Scholes model should a change of control occur.
	Changes resulting from the revaluation of warrants to fair value are recorded in “Revaluation of warrant liability” on the condensed consolidated statements of operations. Upon the exercise or modification to remove the provisions which require the warrants to be treated as a liability, the fair value of the warrants will be reclassified from a liability to stockholders’ equity on the Company’s condensed consolidated balance sheets and no further adjustment to the fair value would be made in subsequent periods.
	See Note 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of warrant liability.
	Income Taxes
	The Company accounts for income taxes using an asset and liability approach in accordance with ASC Topic 740 “Accounting for Income Taxes.” Under this method, deferred tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. ASC Topic 740 requires derecognition of tax positions that do not have a greater than 50% likelihood of being recognized upon review by a taxing authority having full knowledge of all relevant information. Use of a valuation allowance as described in ASC Topic 740 is not an appropriate substitute for the derecognition of a tax position. The Company recognizes accrued interest and penalties related to unrecognized tax benefits in its income tax expense. To date, the Company has not recognized any interest and penalties in its condensed consolidated statements of operations, nor has its accrued for or made payments for interest and penalties. The Company continues to carry a full valuation allowance on all of its deferred tax assets. Although the Company believes it more likely than not that a taxing authority would agree with its current tax positions, there can be no assurance that the tax positions the Company has taken will be substantiated by a taxing authority if reviewed. The Company’s tax years 1998 through 2013 remain subject to examination by the taxing jurisdictions due to unutilized net operating losses and research credits.
	Net Income (Loss) Per Share
	Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share gives effect to all potentially dilutive common shares outstanding for the period. The potentially dilutive securities include stock options, employee stock purchase plan rights, warrants and restricted stock units, which are calculated using the treasury stock method. Diluted net income (loss) per share also gives effect to potential adjustments to the numerator for changes resulting from the revaluation of warrants to fair value for the period, even if the Company is in a net loss position, if the effect would result in more dilution.
	Certain potential dilutive securities were excluded from the dilution calculation for the three months ended March 31, 2014, and 2013, as their inclusion would have been anti-dilutive.
	The following table sets forth the reconciliation of the numerator and denominator used in the computation of basic and diluted net income (loss) per share for the three months ended March 31, 2014, and 2013 (in thousands, except per share amounts):
		Three Months Ended
		March 31,
		2014			2013
	Numerator for Basic and Diluted:
	Net loss used for basic calculation	$	(225	)	$	(10,252	)
	Effect of revaluation of warrant liability		(9,034	)		0
	Adjusted net loss used for diluted calculation	$	(9,259	)	$	(10,252	)
	Denominator:
	Basic weighted average number of shares outstanding		72,088			59,730
Effect of dilutive potential shares		3,070			0
Diluted weighted average number of shares outstanding		75,158			59,730
Net loss per share:
Basic	$	(0.00	)	$	(0.17	)
Diluted	$	(0.12	)	$	(0.17	)
The table below presents shares underlying stock options, employee stock purchase plan rights, warrants and restricted stock units that are excluded from the calculation of the weighted average number of shares outstanding used for the calculation of diluted net loss per share. These are excluded from the calculation due to their anti-dilutive effect for the three months ended March 31, 2014 and 2013 (shares in thousands):
	Three Months Ended
	March 31,
	2014			2013
Weighted average number of anti-dilutive potential shares		16,901			15,531
Guarantee and Indemnification Arrangements
The Company recognizes the fair value for guarantee and indemnification arrangements issued or modified by the Company after December 31, 2002. In addition, the Company monitors the conditions that are subject to the guarantees and indemnifications in order to identify if a loss has occurred. If the Company determines it is probable that a loss has occurred, then any such estimable loss would be recognized under those guarantees and indemnifications. Some of the agreements that the Company is a party to contain provisions that indemnify the counter party from damages and costs resulting from claims that the Company’s technology infringes the intellectual property rights of a third party or claims that the sale or use of the Company’s products have caused personal injury or other damage or loss. The Company has not received any such requests for indemnification under these provisions and has not been required to make material payments pursuant to these provisions.
The Company generally provides for a one-year warranty on certain of its INTERCEPT blood-safety products covering defects in materials and workmanship. The Company accrues costs associated with warranty obligations when claims become known and are estimable.
Fair Value of Financial Instruments
The Company applies the provisions of fair value relating to its financial assets and liabilities. The carrying amounts of accounts receivables, accounts payable, and other accrued liabilities approximate their fair value due to the relative short-term maturities. Based on the borrowing rates currently available to the Company for loans with similar terms, the Company believes the fair value of its debt approximates its carrying amounts. The Company measures and records certain financial assets and liabilities at fair value on a recurring basis, including its available-for-sale securities and warrant liability. The Company classifies instruments within Level 1 if quoted prices are available in active markets for identical assets, which include the Company’s cash accounts and money market funds. The Company classifies instruments in Level 2 if the instruments are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. These instruments include the Company’s available-for-sale securities related to corporate debt and United States government agency securities. The available-for-sale securities are held by a custodian who obtains investment prices from a third party pricing provider that uses standard inputs (observable in the market) to models which vary by asset class. The Company classifies instruments in Level 3 if one or more significant inputs or significant value drivers are unobservable, which include its warrant liability. The Company assesses any transfers among fair value measurement levels at the end of each reporting period.
See Note 2 and 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of financial instruments.
New Accounting Pronouncements
There have been no new accounting pronouncements issued during the three months ending March 31, 2014 that are of significance, or potential significance, to the Company.

Fair_Value_on_Financial_Instru

Fair Value on Financial Instruments	3 Months Ended
	Mar. 31, 2014
Fair Value on Financial Instruments	'
	Note 2. Fair Value on Financial Instruments
	The Company determines the fair value of an asset or liability based on the assumptions that market participants would use in pricing the asset or liability in an orderly transaction between market participants at the measurement date. The identification of market participant assumptions provides a basis for determining what inputs are to be used for pricing each asset or liability. A fair value hierarchy has been established which gives precedence to fair value measurements calculated using observable inputs over those using unobservable inputs. This hierarchy prioritized the inputs into three broad levels as follows:
		•		Level 1: Quoted prices in active markets for identical instruments
		•		Level 2: Other significant observable inputs (including quoted prices in active markets for similar instruments)
		•		Level 3: Significant unobservable inputs (including assumptions in determining the fair value of certain investments)
	Money market funds are highly liquid investments and are actively traded. The pricing information on these investment instruments are readily available and can be independently validated as of the measurement date. This approach results in the classification of these securities as Level 1 of the fair value hierarchy.
	To estimate the fair value of Level 2 debt securities as of March 31, 2014 the Company’s primary service relies on inputs from multiple industry-recognized pricing sources to determine the price for each investment. Corporate debt and United States government agency securities are systematically priced by this service as of the close of business each business day. If the primary pricing service does not price a specific asset, a secondary pricing service is utilized.
	The fair values of the Company’s financial assets and liabilities were determined using the following inputs at March 31, 2014 (in thousands):
			Total			Quoted		Significant		Significant
						Prices in		Other		Unobservable
						Active		Observable		Inputs
						Markets for		Inputs		(Level 3)
						Identical		(Level 2)
						Assets
						(Level 1)
	Money market funds (1)		$	9,648		$	9,648	$	0	$	0
	Corporate debt securities (2)			20,251			0		20,251		0
	United States government agency securities (2)			4,012			0		4,012		0
	Total financial assets		$	33,911		$	9,648	$	24,263	$	0
	Warrant liability (3)		$	11,356		$	0	$	0	$	11,356
	Total financial liabilities		$	11,356		$	0	$	0	$	11,356
	-1	Included in cash and cash equivalents on the Company’s condensed consolidated balance sheets.
	-2	Included in short-term investments on the Company’s condensed consolidated balance sheets.
	-3	Included in current liabilities on the Company’s condensed consolidated balance sheets.
	The fair values of the Company’s financial assets and liabilities were determined using the following inputs at December 31, 2013 (in thousands):
			Total			Quoted		Significant		Significant
						Prices in		Other		Unobservable
						Active		Observable		Inputs
						Markets for		Inputs		(Level 3)
						Identical		(Level 2)
						Assets
						(Level 1)
	Money market funds (1)		$	8,650		$	8,650	$	0	$	0
	Corporate debt securities (2)			23,173			0		23,173		0
	United States government agency securities (2)			5,018			0		5,018		0
	Total financial assets		$	36,841		$	8,650	$	28,191	$	0
	Warrant liability (3)		$	20,390		$	0	$	0	$	20,390
	Total financial liabilities		$	20,390		$	0	$	0	$	20,390
	-1	Included in cash and cash equivalents on the Company’s condensed consolidated balance sheets.
	-2	Included in short-term investments on the Company’s condensed consolidated balance sheets.
	-3	Included in current liabilities on the Company’s condensed consolidated balance sheets.
	A reconciliation of the beginning and ending balances for warrant liability using significant unobservable inputs (Level 3) from December 31, 2013 to March 31, 2014 was as follows (in thousands):
	Balance at December 31, 2013		$	20,390
	Decrease in fair value of warrants			(9,034	)
	Balance at March 31, 2014		$	11,356
	See Note 1 and 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation techniques and unobservable inputs for warrant liability using significant unobservable inputs (Level 3).
	The Company did not have any transfers among fair value measurement levels during the three months ended March 31, 2014 or the year ended December 31, 2013.

Availableforsale_Securities

Available-for-sale Securities	3 Months Ended
	Mar. 31, 2014
Available-for-sale Securities	'
	Note 3. Available-for-sale Securities
	The following is a summary of available-for-sale securities at March 31, 2014 (in thousands):
		March 31, 2014
		Carrying Value		Gross			Fair Value
				Unrealized Gain
	Money market funds	$	9,648	$	0		$	9,648
	Corporate debt securities		20,243		8			20,251
	United States government agency securities		4,012		0			4,012
	Total available-for-sale securities	$	33,903	$	8		$	33,911
	The following is a summary of available-for-sale securities at December 31, 2013 (in thousands):
		December 31, 2013
		Carrying Value		Gross			Fair Value
				Unrealized Gain
	Money market funds	$	8,650	$	0		$	8,650
	Corporate debt securities		23,165		8			23,173
	United States government agency securities		5,019		(1	)		5,018
	Total available-for-sale securities	$	36,834	$	7		$	36,841
	Available-for-sale securities at March 31, 2014 and December 31, 2013 consisted of the following by original contractual maturity (in thousands):
		March 31, 2014					December 31, 2013
		Carrying Value		Fair Value			Carrying Value		Fair Value
	Due in one year or less	$	33,903	$	33,911		$	30,700	$	30,701
	Due greater than one year and less than three years		0		0			6,134		6,140
	Total cash equivalents and short-term investments	$	33,903	$	33,911		$	36,834	$	36,841
	The Company did not record any gross realized gains from the sale or maturity of available-for-sale investments during the three months ended March 31, 2014 and 2013. The Company did not record losses on investments experiencing an other-than-temporary decline in fair value nor did it record any gross realized losses from the sale or maturity of available-for-sale investments during the three months ended March 31, 2014 and 2013, respectively.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2014
Inventories	'
	Note 4. Inventories
	Inventories at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Work-in-process	$	2,142	$	4,863
	Finished goods		9,165		8,200
	Total inventories	$	11,307	$	13,063

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets, net	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets, net	'
	Note 5. Goodwill and Intangible Assets, net
	Goodwill
	During the three months ended March 31, 2014, the Company did not dispose of or recognize additional goodwill. The Company expects to perform its annual review of goodwill on August 31, 2014, unless indicators of impairment are identified prior to that date. As of March 31, 2014, the Company has not identified any indicators of goodwill impairment.
	Intangible Assets, net
	The following is a summary of intangible assets, net at March 31, 2014 (in thousands):
		March 31, 2014
		Gross		Accumulated			Net
		Carrying		Amortization			Carrying
		Amount					Amount
	Acquisition-related intangible assets:
	Reacquired license - INTERCEPT Asia	$	2,017	$	(723	)	$	1,294
	Total intangible assets	$	2,017	$	(723	)	$	1,294
	The following is a summary of intangible assets, net at December 31, 2013 (in thousands):
		December 31, 2013
		Gross		Accumulated			Net
		Carrying		Amortization			Carrying
		Amount					Amount
	Acquisition-related intangible assets:
	Reacquired license - INTERCEPT Asia	$	2,017	$	(673	)	$	1,344
	Total intangible assets	$	2,017	$	(673	)	$	1,344
	The Company recognized $0.05 million in amortization expense related to intangible assets for each of the three months ended March 31, 2014 and 2013. During the three months ended March 31, 2014 and 2013, there were no impairment charges recognized related to the acquired intangible assets.
	At March 31, 2014, the expected annual amortization expense of the intangible assets, net is $0.15 million for the remaining nine months of 2014, $0.2 million annually beginning with the year ending December 31, 2015 through the year ending December 31, 2019, and $0.1 million for the year ending December 31, 2020.

LongTerm_Investments

Long-Term Investments	3 Months Ended
	Mar. 31, 2014
Long-Term Investments	'
	Note 6. Long-Term Investments
	In connection with the agreements to license the immunotherapy technologies to Aduro BioTech (“Aduro”) in 2009, the Company received preferred shares of Aduro. Pursuant to these license agreements, the Company is eligible to receive a 1% royalty fee on any future sales resulting from the licensed technology. As of March 2014, the Company’s ownership in Aduro was less than 3% on a fully diluted basis. Since receiving preferred stock in Aduro, the Company has carried its investment in Aduro at zero in its condensed consolidated balance sheet. As of March 31, 2014, the Company has not received any royalties under this agreement.

Accrued_Liabilities

Accrued Liabilities	3 Months Ended
	Mar. 31, 2014
Accrued Liabilities	'
	Note 7. Accrued Liabilities
	Accrued liabilities at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Accrued compensation and related costs	$	1,899	$	2,527
	Accrued inventory costs		2,534		3,553
	Accrued professional services		2,995		2,722
	Other accrued expenses		1,410		1,011
	Total accrued liabilities	$	8,838	$	9,813

Debt

Debt	3 Months Ended
	Mar. 31, 2014
Debt	'
	Note 8. Debt
	Debt at March 31, 2014 consisted of the following (in thousands):
		March 31, 2014
		Principal			Unamortized		Total
					Discount
	Comerica - Revolving Line of Credit, due 2014	$	3,268		$	0	$	3,268
	Less: debt - current		(3,268	)		0		(3,268	)
	Debt - non-current	$	0		$	0	$	0
	Debt at December 31, 2013 consisted of the following (in thousands):
		December 31, 2013
		Principal			Unamortized		Total
					Discount
	Comerica - Revolving Line of Credit, due 2014	$	3,366		$	0	$	3,366
	Less: debt - current		(3,366	)		0		(3,366	)
	Debt - non-current	$	0		$	0	$	0
	Principal and interest payments on debt at March 31, 2014 are expected to be $3.3 million through June 2014 when the Revolving Line of Credit becomes due.
	2011 Growth Capital Facility
	The Company entered into a loan and security agreement on September 30, 2011, as amended effective on December 13, 2011, and June 30, 2012, with Comerica Bank (“Comerica”) (collectively, the “Amended Credit Agreement”). The Amended Credit Agreement provides for an aggregate borrowing of up to $12.0 million, comprised of a growth capital loan of $5.0 million (“Growth Capital Loan”) and a formula based revolving line of credit (“RLOC”) of up to $7.0 million. The Company pledged all current and future assets, excluding its intellectual property and 35% of the Company’s investment in its subsidiary, Cerus Europe B.V., as security for borrowings under the Amended Credit Agreement.
	Growth Capital Loan
	Concurrent with the execution of the original loan and security agreement in September 2011, the Company borrowed $5.0 million under the Growth Capital Loan, substantially all of which was used to repay the Company’s prior debt with Oxford Finance Corporation (“Oxford”), with the remainder used for general corporate purposes. The Growth Capital Loan was scheduled to mature on September 30, 2015 and bore a fixed interest rate of 6.37%, with interest–only payments due for the first twelve months, followed by equal principal and interest payments for the remaining 36 months. In April 2013, the Company repaid in full the Growth Capital Loan balance and all accrued interest as well as a scheduled final payment fee of $0.05 million, in an aggregate amount of $4.2 million. The Company has no further obligations under the Growth Capital Loan.
	Revolving Line of Credit
	The Amended Credit Agreement also provides for a RLOC of up to $7.0 million (the “RLOC Loan Amount”). The amount available under the RLOC is limited to the lesser of (i) 80% of eligible trade receivables or (ii) the RLOC Loan Amount. At March 31, 2014, and December 31, 2013, the Company had $3.3 million and $3.4 million, respectively, outstanding under the RLOC. The Company is required to repay the principal drawn from the RLOC at the end of the RLOC term on June 30, 2014, or earlier if a portion or all of the outstanding RLOC exceeds the amount available under the RLOC. The RLOC bears a floating rate based on the lender’s prime rate plus 1.50%, with interest–only payments due each month. At both March 31, 2014, and December 31, 2013, the floating rate of the RLOC was 4.75%.
	Compliance with Covenants
	The Company is required to maintain compliance with certain customary and routine financial covenants under the Amended Credit Agreement, including maintaining a minimum cash balance of $2.5 million at Comerica and achieving minimum revenue levels, which are measured monthly based on a six-month trailing basis and must be at least 75% of the pre-established future projected revenues for the trailing six-month period. Non-compliance with the covenants could result in the principal of the note becoming due and payable. As of March 31, 2014, the Company was in compliance with the financial covenants as set forth in the Amended Credit Agreement.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies	'
	Note 9. Commitments and Contingencies
	Operating Leases
	The Company leases its office facilities, located in Concord, California and Amersfoort, The Netherlands, and certain equipment under non-cancelable operating leases with initial terms in excess of one year that require the Company to pay operating costs, property taxes, insurance and maintenance. The operating leases expire at various dates through 2019, with certain of the leases providing for renewal options, provisions for adjusting future lease payments, which is based on the consumer price index and the right to terminate the lease early, which may occur as early as January 2015. In June 2013, the Company entered into a new lease for additional space in Concord. The lease has a two year initial term with four (4) two year options for the Company to renew. The lease commenced on August 1, 2013 and obligates the Company to make rent payments for the remaining nine months of $115,776 and $90,048 in 2014 and 2015, respectively. The Company’s leased facilities qualify as operating leases under ASC Topic 840, “Leases” and as such, are not included on its condensed consolidated balance sheets.
	Financed Leasehold Improvements
	In 2010, the Company financed $1.1 million of leasehold improvements at one of its facilities in Concord, California. The Company pays for the financed leasehold improvements as a component of rent and is required to reimburse its landlord over the remaining life of the respective leases. If the Company exercises its right to early terminate the Concord California lease under which such improvements were made, which may occur as early as January 2015, the Company would be required to repay for any remaining portion of the landlord financed leasehold improvements at such time. At March 31, 2014, the Company had an outstanding liability of $0.7 million related to these leasehold improvements, of which $0.1 million was reflected in “Accrued liabilities” and $0.6 million was reflected in “Other non-current liabilities” on the Company’s condensed consolidated balance sheets.
	Purchase Commitments
	The Company is party to agreements with certain providers for certain components of INTERCEPT Blood System which the Company purchases from third party manufacturers and supplies to Fresenius at no cost for use in manufacturing finished INTERCEPT disposable kits. Certain of these agreements require minimum purchase commitments from the Company.

Stockholders_Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2014
Stockholders' Equity	'
	Note 10. Stockholders’ Equity
	Common Stock and Associated Warrant Liability
	In August 2009, the Company issued warrants to purchase 2.4 million shares of common stock, exercisable at an exercise price of $2.90 per share (“2009 Warrants”). The 2009 Warrants are exercisable for a period of five years from the issue date. The fair value on the date of issuance of the 2009 Warrants was determined to be $2.8 million using the Black-Scholes model and/or binomial-lattice option valuation model and applying the following assumptions: (i) a risk-free rate of 2.48%, (ii) an expected term of 5.0 years, (iii) no dividend yield and (iv) a volatility of 77%.
	In November 2010, the Company received net proceeds of approximately $19.7 million, after deducting underwriting discounts and commissions and stock issuance costs of approximately $1.3 million, from an underwritten public offering of 7.4 million units. Each unit sold consisted of one share of common stock and a warrant to purchase 1/2 of a share of common stock. Each unit was sold for $2.85, resulting in the issuance of 7.4 million shares of common stock and warrants to purchase 3.7 million shares of common stock, exercisable at an exercise price of $3.20 per share (“2010 Warrants”). The warrants issued in November 2010 became exercisable on May 15, 2011 and are exercisable for a period of five years from the issue date. The fair value on the date of issuance of the 2010 Warrants was determined to be $5.8 million using the Black-Scholes model and/or binomial-lattice option valuation model and applying the following assumptions: (i) a risk-free rate of 1.23%, (ii) an expected term of 5.0 years, (iii) no dividend yield and (iv) a volatility of 85%.
	The fair value of the 2009 Warrants and 2010 Warrants was recorded on the consolidated balance sheets as a liability pursuant to “Accounting for Derivative Instruments and Hedging Activities” and “Accounting for Certain Financial Instruments with Characteristics of Both Liabilities and Equity” Topics of ASC and will be adjusted to fair value at each financial reporting date thereafter until the earlier of exercise or modification to remove the provisions which require the warrants to be treated as a liability, at which time, these warrants would be reclassified into stockholders’ equity. The Company classified the 2009 Warrants and 2010 Warrants as a liability as these warrants contain certain provisions that, under certain circumstances, which may be out of the Company’s control, could require the Company to pay cash to settle the exercise of the warrants or may require the Company to redeem the warrants.
	The fair value of the warrants at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,			December 31,
		2014			2013
	2009 Warrants	$	4,637		$	8,542
	2010 Warrants		6,719			11,848
	Total warrant liability	$	11,356		$	20,390
	The fair value of the Company’s warrants was based on using the binomial-lattice option valuation model and using the following assumptions at March 31, 2014 and December 31, 2013:
		March 31,			December 31,
		2014			2013
	2009 Warrants:
	Expected term (in years)		0.4			0.65
	Estimated volatility		52	%		45	%
	Risk-free interest rate		0.07	%		0.1	%
	Expected dividend yield		0	%		0	%
	2010 Warrants:
	Expected term (in years)		1.61			1.86
	Estimated volatility		45	%		41	%
	Risk-free interest rate		0.44	%		0.38	%
	Expected dividend yield		0	%		0	%
	The Company recorded a non-cash gain of $9.0 million and a non-cash loss of $5.1 million during the three months ended March 31, 2014, and 2013, respectively, in “Gain (Loss) from Revaluation of warrant liability” on the condensed consolidated statements of operations due to the changes in fair value of the warrants. Significant changes to the Company’s market price for its common stock will impact the implied and/or historical volatility used to fair value the warrants. Any significant increases in the Company’s stock price will likely create an increase to the fair value of warrant liability. Similarly, any significant decreases in the Company’s stock price will likely create a decrease to the fair value of warrant liability. During the three months ended March 31, 2014, there were no exercises of these warrants. In 2013, warrants to purchase 186,586 shares of common stock were exercised from the outstanding 2010 Warrants.
	Sales Agreements
	The Company entered into an At-The-Market Issuance Sales Agreement in June 2011, as amended in January 2012 and August 2012 (as amended, the “MLV Agreement”), with MLV & Co. LLC, formerly McNicoll, Lewis & Vlak LLC (“MLV”) that provides for the issuance and sale of shares of the Company’s common stock over the term of the MLV Agreement having an aggregate offering price of up to $20.0 million through MLV. At March 31, 2014, the Company had less than $0.1 million of common stock available to be sold under the MLV Agreement. During the three months ended March 31, 2014, the Company had no sales of its common stock under the MLV Agreement. The MLV Agreement expires in June 2014.
	On March 21, 2014, the Company entered into Amendment No. 1 to the Controlled Equity OfferingSM Sales Agreement, dated August 31, 2012 (as amended, the “Amended Cantor Agreement”) with Cantor Fitzgerald & Co. (“Cantor”) that provides for the issuance and sale of shares of its common stock over the term of the Amended Cantor Agreement having an aggregate offering price of up to an aggregate of $70.0 million through Cantor. Under the Amended Cantor Agreement, Cantor also acts as the Company’s sales agent and receives compensation based on an aggregate of 2% of the gross proceeds on the sale price per share of its common stock. The issuance and sale of these shares by the Company pursuant to the Amended Cantor Agreement are deemed an “at-the-market” offering and are registered under the Securities Act. During the year ended December 31, 2013, approximately 5.4 million shares of the Company’s common stock were sold under the Amended Cantor Agreement for aggregate net proceeds of $23.5 million. During the three months ended March 31, 2014, the Company had no sales of its common stock under the Amended Cantor Agreement. At March 31, 2014, the Company had approximately $41.5 million of common stock available to be sold under the Amended Cantor Agreement.
	Public Offering of Common Stock
	The Company completed a public offering of common stock on March 19, 2013. As a result of this offering, the Company issued approximately 8.3 million shares of its common stock at $4.20 per share. The Company provided the underwriters an overallotment of an additional approximately 1.3 million shares of its common stock, which was fully subscribed. Combined gross proceeds for the offering were approximately $40.3 million. Net proceeds to the Company were approximately $38.0 million after underwriters’ discount of approximately $1.8 million and offering costs of approximately $0.5 million.
	Stockholder Rights Plan
	In October 2009, the Company’s Board of Directors adopted an amendment to its 1999 stockholder rights plan, commonly referred to as a “poison pill,” to reduce the exercise price, extend the expiration date and revise certain definitions under the plan. The stockholder rights plan is intended to deter hostile or coercive attempts to acquire the Company. The stockholder rights plan enables stockholders to acquire shares of the Company’s common stock, or the common stock of an acquirer, at a substantial discount to the public market price should any person or group acquire more than 15% of the Company’s common stock without the approval of the Board of Directors under certain circumstances. The Company has designated 250,000 shares of Series C Junior Participating preferred stock for issuance in connection with the stockholder rights plan.

StockBased_Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2014
Stock-Based Compensation	'
	Note 11. Stock-Based Compensation
	The Company maintains an equity compensation plan to provide long-term incentives for employees, contractors, and members of its Board of Directors. The Company currently grants equity awards from one plan, the 2008 Equity Incentive Plan (the “2008 Plan”). The 2008 Plan allows for the issuance of non-statutory and incentive stock options, restricted stock, restricted stock units, stock appreciation rights, other stock-related awards, and performance awards which may be settled in cash, stock, or other property. The Company continues to have equity awards outstanding under its previous stock plans: 1998 Non-Officer Stock Option Plan and 1999 Equity Incentive Plan (collectively, the “Prior Plans”) and 1996 Equity Incentive Plan (the “1996 Plan”). Equity awards issued under the Prior Plans and the 1996 Plan continue to adhere to the terms of those respective stock plans and no further options may be granted under those previous plans. However, at June 2, 2008, any shares that remained available for future grants under the Prior Plans became available for issuance under the 2008 Plan. On each of June 6, 2012 and June 12, 2013, the stockholders approved an amendment to the 2008 Plan (“Amended 2008 Plan”) which increased the aggregate number of shares of common stock authorized for issuance by 3,000,000 and 6,000,000 shares, respectively, such that the Amended 2008 Plan has reserved for issuance an amount not to exceed 19,540,940 shares effective June 12, 2013. At March 31, 2014, the Company had an aggregate of approximately 18.1 million shares of its common stock reserved for issuance under the Amended 2008 Plan, the Prior Plans and the 1996 Plan, of which approximately 12.3 million shares were subject to outstanding options and other stock-based awards, and approximately 5.8 million shares were available for future issuance under the Amended 2008 Plan.
	The Company also maintains an Employee Stock Purchase Plan (the “Purchase Plan”) which is intended to qualify as an employee stock purchase plan within the meaning of Section 423(b) of the Internal Revenue Code. Under the Purchase Plan, the Company’s Board of Directors may authorize participation by eligible employees, including officers, in periodic offerings. On June 6, 2012, the stockholders approved an amendment to the Purchase Plan to increase the aggregate number of shares of common stock authorized for issuance by 500,000 shares, such that the Purchase Plan has reserved for issuance an amount not to exceed 1,320,500 shares. At March 31, 2014, the Company had approximately 0.5 million shares available for future issuance under the Purchase Plan.
	The Company has granted restricted stock units primarily to its senior management in accordance with the Amended 2008 Plan. Subject to each grantee’s continued employment, the restricted stock units generally vest in three annual installments from the date of grant and are generally issuable at the end of the three-year vesting term. At March 31, 2014, all restricted stock units were fully vested.
	Activity under the Company’s equity incentive plans related to stock options is set forth below (in thousands except per share amounts):
		Number of			Weighted
		Options			Average
		Outstanding			Exercise
					Price per
					Share
	Balances at December 31, 2013		10,405		$	3.46
	Granted		2,347			6.2
	Forfeited		(36	)		4.49
	Expired		(30	)		9.78
	Exercised		(478	)		2.65
	Balances at March 31, 2014		12,208		$	4
	The Company uses the Black-Scholes option pricing model to determine the grant-date fair value of stock options and employee stock purchase plan shares. The Black-Scholes option pricing model is affected by the Company’s stock price, as well as assumptions regarding a number of complex and subjective variables, which include the expected term of the grants, actual and projected employee stock option exercise behaviors, including forfeitures, the Company’s expected stock price volatility, the risk-free interest rate and expected dividends. The Company recognizes the grant-date fair value of the stock award as stock-based compensation expense on a straight-line basis over the requisite service period, which is the vesting period, and is adjusted for estimated forfeitures.
	Stock-based compensation recognized on the Company’s condensed consolidated statements of operations for the three months ended March 31, 2014 and 2013, was as follows (in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Stock-based compensation expense by caption:
	Research and development	$	183		$	87
	Selling, general and administrative		762			626
	Total stock-based compensation expense	$	945		$	713
	The Company did not record any stock-based compensation associated with performance-based stock options during the three months ended March 31, 2014 and 2013 as the performance criteria was not probable of being achieved. Performance-based stock options of 50,000 remained outstanding at March 31, 2014.

Development_and_License_Agreem

Development and License Agreements	3 Months Ended
	Mar. 31, 2014
Development and License Agreements	'
	Note 12. Development and License Agreements
	Agreements with Fresenius
	The Company has certain agreements with Fresenius which require the Company to pay royalties on INTERCEPT Blood System product sales at royalty rates that vary by product: 10% of product sales for the platelet system and 3% of product sales for the plasma system. During the three months ended March 31, 2014, and 2013, the Company made royalty payments to Fresenius of $0.7 million and $0.8 million, respectively. At March 31, 2014, and December 31, 2013, accrued royalties due to Fresenius were $0.6 million and $0.7 million, respectively.
	The Company also paid Fresenius certain costs associated with the amended manufacturing and supply agreement the Company executed with Fresenius in December 2008 (the “Original Supply Agreement”), for the manufacture of INTERCEPT finished disposable kits for the Company’s platelet and plasma systems through December 31, 2013. Under the Original Supply Agreement, the Company paid Fresenius a set price per disposable kit, which was established annually, plus a fixed surcharge per disposable kit. In addition, volume driven manufacturing overhead was paid or refunded if actual manufacturing volumes were higher or lower than the annually estimated production volumes. The Company made payments to Fresenius of $4.6 million and $3.9 million relating to the manufacturing of the Company products during the three months ended March 31, 2014, and 2013, respectively. At March 31, 2014, and December 31, 2013, accrued amounts due to Fresenius were $3.4 million and $4.3 million, respectively, for INTERCEPT disposable kits manufactured.
	In November 2013, the Company amended the Original Supply Agreement with Fresenius, with the new terms effective January 1, 2014 (the “2013 Amendment”). Under the 2013 Amendment, Fresenius is obligated to sell, and the Company is obligated to purchase, up to a certain specified annual volume of finished disposable kits for the platelet and plasma systems from Fresenius for both clinical and commercial use. Once the specified annual volume of disposable kits is purchased from Fresenius, the Company is able to purchase additional quantities of disposable kits from other third-party manufacturers. The 2013 Amendment also provides for fixed pricing for finished kits with successive decreases in pricing at certain annual production volumes. In addition, the 2013 Amendment requires the Company to purchase additional specified annual volumes of sets per annum if and when an additional Fresenius manufacturing site is identified and qualified to make INTERCEPT disposable kits subject to mutual agreement on pricing for disposable kits manufactured at the additional site. Fresenius is also obligated to purchase and maintain specified inventory levels of the Company’s proprietary inactivation compounds and adsorption media from the Company at fixed prices. During the three months ended March 31, 2014, we sold $2.7 million of such components to Fresenius. We maintain the value of components sold to Fresenius as a current asset on our balance sheet until such time as we purchase finished disposable kits using those components. The term of the 2013 Amendment extends through December 31, 2018, subject to termination by either party upon thirty months prior written notice, in the case of Fresenius, or twenty-four months prior written notice, in the Company’s case. The Company and Fresenius each have normal and customary termination rights, including termination for material breach.

Segment_Customer_and_Geographi

Segment, Customer and Geographic Information	3 Months Ended
	Mar. 31, 2014
Segment, Customer and Geographic Information	'
	Note 13. Segment, Customer and Geographic Information
	The Company continues to operate in only one segment, blood safety. The Company’s chief executive officer is the chief operating decision maker who evaluates performance based on the net revenues and operating loss of the blood safety segment. The Company considers the sale of all of its INTERCEPT Blood System products to be similar in nature and function, and any revenue earned from services are minimal.
	The Company’s operations outside of the United States include a wholly-owned subsidiary headquartered in Europe. The Company’s operations in the United States are responsible for the research and development and global commercialization of the INTERCEPT Blood System, as discussed in further detail below, while operations in Europe are responsible for the commercialization efforts of the platelet and plasma systems in Europe, The Commonwealth of Independent States and the Middle East. Product revenues are attributed to each region based on the location of the customer, and in the case of non-product revenues, on the location of the collaboration partner.
	The Company had the following significant customers that accounted for more than 10% of the Company’s total product revenue, all of which operate in a country outside of the United States, during the three months ended March 31, 2014 and 2013 (in percentages):
			Three Months Ended
			March 31,
			2014			2013
	Etablissement Francais du Sang			23	%		16	%
	Movaco, S.A.			19	%		19	%
	Delrus Inc.				*		19	%
	*	Represents an amount less than 10% of product revenue.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Principles of Consolidation and Basis of Presentation	'
	Principles of Consolidation and Basis of Presentation
	The accompanying unaudited condensed consolidated financial statements include those of Cerus Corporation and its subsidiary, Cerus Europe B.V. (collectively referred to hereinafter as “Cerus” or the “Company”) after elimination of all intercompany accounts and transactions. These condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) for interim financial information and pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. In the opinion of management, all adjustments, consisting of normal recurring entries, considered necessary for a fair presentation have been made. Operating results for the three months ended March 31, 2014, are not necessarily indicative of the results that may be expected for the year ending December 31, 2014, or for any future periods.
	These condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto for the year ended December 31, 2013, which were included in the Company’s 2013 Annual Report on Form 10-K, filed with the SEC on March 7, 2014. The accompanying consolidated balance sheet as of December 31, 2013 has been derived from the Company’s audited consolidated financial statements as of that date.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements requires management to make estimates, assumptions and judgments that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosures of contingent assets and liabilities. On an ongoing basis, management evaluates its estimates, which are based on historical experience and on various other assumptions that are believed to be reasonable under the circumstances. Actual results may differ from those estimates under different assumptions or conditions.
Revenue	'
	Revenue
	The Company recognizes revenue in accordance with ASC Topic 605-25, “Revenue Recognition – Arrangements with Multiple Deliverables,” as applicable. Revenue is recognized when (i) persuasive evidence of an agreement with the funding party exists; (ii) services have been rendered or product has been delivered; (iii) pricing is fixed or determinable; and (iv) collection is reasonably assured. The Company’s source of revenues for the three months ended March 31, 2014 and 2013 was product revenue from sales of the INTERCEPT Blood System for platelets and plasma (“platelet and plasma systems”).
	Revenue related to product sales is generally recognized when the Company fulfills its obligations for each element of an agreement. For all sales of the Company’s INTERCEPT Blood System products, the Company uses a binding purchase order and signed sales contract as evidence of a written agreement. The Company sells its platelet and plasma systems directly to blood banks, hospitals, universities, government agencies, as well as to distributors in certain regions. Generally, the Company’s contracts with its customers do not provide for open return rights, except within a reasonable time after receipt of goods in the case of defective or non-conforming product. Deliverables and the units of accounting vary according to the provisions of each purchase order or sales contract. For revenue arrangements with multiple elements, the Company determines whether the delivered elements meet the criteria as separate units of accounting. Such criteria require that the deliverable have stand-alone value to the customer and that if a general right of return exists relative to the delivered item, delivery or performance of the undelivered item(s) is considered probable and substantially in the control of the Company. Once the Company determines if the deliverable meets the criteria for a separate unit of accounting, the Company must determine how the consideration should be allocated between the deliverables and how the separate units of accounting should be recognized as revenue. Consideration received is allocated to elements that are identified as discrete units of accounting based on the best estimated selling price. The Company has determined that vendor specific objective evidence is not discernible due to the Company’s variability in its pricing across the regions into which it sells its products. Since the Company’s products are novel and unique and are not sold by others, third-party evidence of selling price is unavailable.
	At March 31, 2014 and December 31, 2013, the Company had $0.3 million and $0.2 million, respectively, of short-term deferred revenue on its condensed consolidated balance sheets related to future performance obligations. Freight costs charged to customers are recorded as a component of revenue under ASC Topic 605, “Accounting for Shipping and Handling Fees and Costs.” Value-added-taxes (“VAT”) that the Company invoices to its customers and remits to governments are recorded on a net basis, which excludes such VAT from product revenue.
Research and Development Expenses	'
	Research and Development Expenses
	In accordance with ASC Topic 730, “Accounting for Research and Development Expenses,” research and development expenses are charged to expense when incurred. Research and development expenses include salaries and related expenses for scientific personnel, payments to consultants, supplies and chemicals used in in-house laboratories, costs of research and development facilities, depreciation of equipment and external contract research expenses, including clinical trials, preclinical safety studies, other laboratory studies, process development and product manufacturing for research use.
	The Company’s use of estimates in recording accrued liabilities for research and development activities (see “Use of Estimates” above) affects the amounts of research and development expenses recorded and revenue recorded from development funding and government grants and collaborative agreements. Actual results may differ from those estimates under different assumptions or conditions.
Cash Equivalents	'
	Cash Equivalents
	The Company considers all highly liquid investments with original maturities of three months or less from the date of purchase to be classified as cash equivalents. These investments primarily consist of money market instruments, and are classified as available-for-sale.
Short-Term Investments	'
	Short-Term Investments
	Investments with original maturities of greater than three months which included corporate debt and United States government agency securities are designated as available-for-sale and classified as short-term investments. In accordance with ASC Topic 320, “Accounting for Certain Investments in Debt and Equity Securities,” the Company classified all debt securities as available-for-sale at the time of purchase and reevaluates such designation as of each balance sheet date. Available-for-sale securities are carried at estimated fair value. Unrealized gains and losses derived by changes in the estimated fair value of available-for-sale securities were recorded in “Net unrealized gains (losses) on available-for-sale securities, net of taxes” on the Company’s condensed consolidated statements of comprehensive loss. Realized gains and losses from the sale of available-for-sale investments were recorded in “Other income, net” on the Company’s condensed consolidated statements of operations. The cost of securities sold was based on the specific identification method. The Company reported the amortization of any premium and accretion of any discount resulting from the purchase of debt securities as a component of interest income.
	The Company also reviews its marketable securities on a regular basis to evaluate whether any security has experienced an other-than-temporary decline in fair value. Other-than-temporary declines in market value are recorded in “Other income (expense), net” on the Company’s condensed consolidated statements of operations.
Restricted Cash	'
	Restricted Cash
	The Company holds a certificate of deposit with a domestic bank for any potential decommissioning resulting from the Company’s possession of radioactive material. The certificate of deposit is held to satisfy the financial surety requirements of the California Department of Health Services and is recorded in “Restricted cash” on the Company’s condensed consolidated balance sheets. The Company also has certain non-US dollar denominated deposits recorded as “Restricted cash” in compliance with certain foreign contractual requirements.
Concentration of Credit Risk	'
	Concentration of Credit Risk
	Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash equivalents, short-term investments and accounts receivable.
	Pursuant to the Company’s investment policy, substantially all of the Company’s cash, cash equivalents and short-term investments are maintained at major financial institutions of high credit standing. The Company monitors the financial credit worthiness of the issuers of its investments and limits the concentration in individual securities and types of investments that exist within its investment portfolio. Generally, all of the Company’s investments carry high credit quality ratings, which is in accordance with its investment policy. At March 31, 2014, the Company does not believe there is significant financial risk from non-performance by the issuers of the Company’s cash equivalents.
	Concentrations of credit risk with respect to trade receivables exist. However, in connection with the Company’s revolving line of credit, as discussed in Note 8 in the Notes to Condensed Consolidated Financial Statements, the Company purchased a credit insurance policy that mitigates some of its credit risk, as the policy will pay either the Company or its lender on eligible claims filed on its outstanding receivables. On a regular basis, including at the time of sale, the Company performs credit evaluations of its customers. Generally, the Company does not require collateral from its customers to secure accounts receivable. To the extent that the Company determines specific invoices or customer accounts may be uncollectible, the Company reserves against the accounts receivable on its condensed consolidated balance sheets and records a charge on its condensed consolidated statements of operations. At March 31, 2014 and December 31, 2013, the Company had not recorded any reserves for potentially uncollectible accounts.
	The Company had three customers and two customers that accounted for more than 10% of the Company’s outstanding trade receivables at March 31, 2014, and December 31, 2013, respectively. These customers cumulatively represented approximately 65% and 55% of the Company’s outstanding trade receivables at March 31, 2014, and December 31, 2013, respectively. To date, the Company has not experienced collection difficulties from these customers.
Inventories	'
	Inventories
	At March 31, 2014, and December 31, 2013, inventory consisted of work-in-process and finished goods only. Finished goods include INTERCEPT disposable kits, UVA illumination devices (“illuminators”), and certain replacement parts for the illuminators. Platelet and plasma systems’ disposable kits generally have a two-year life from the date of manufacture. Illuminators and replacement parts do not have regulated expiration dates. Work-in-process includes certain components that are manufactured over a protracted length of time before being sold to and ultimately incorporated and assembled by Fresenius, Inc. (“Fresenius”) into the finished INTERCEPT disposable kits. The Company maintains an inventory balance based on its current sales projections, and at each reporting period, the Company evaluates whether its work-in-process inventory would be sold to Fresenius for production of finished units in order to sell to existing and prospective customers within the next twelve-month period. It is not customary for the Company’s production cycle for inventory to exceed twelve months. Instead, the Company uses its best judgment to factor in lead times for the production of its work-in-process and finished units to meet the Company’s forecasted demands. If actual results differ from those estimates, work-in-process inventory could potentially accumulate for periods exceeding one year. At March 31, 2014 and December 31, 2013, the Company classified its work-in-process inventory as a current asset on its condensed consolidated balance sheets based on its evaluation that the work-in-process inventory would be sold to Fresenius for finished disposable kit production within each respective subsequent twelve-month period.
	Inventory is recorded at the lower of cost, determined on a first-in, first-out basis, or market value. The Company uses significant judgment to analyze and determine if the composition of its inventory is obsolete, slow-moving or unsalable and frequently reviews such determinations. The Company writes-down specifically identified unusable, obsolete, slow-moving, or known unsalable inventory that has no alternative use in the period that it is first recognized by using a number of factors including product expiration dates, open and unfulfilled orders, and sales forecasts. Any write-down of its inventory to net realizable value establishes a new cost basis and will be maintained even if certain circumstances suggest that the inventory is recoverable in subsequent periods. Costs associated with the write-down of inventory are recorded in “Cost of product revenue” on the Company’s condensed consolidated statements of operations. At March 31, 2014, and December 31, 2013, the Company had $0.3 million and $0.4 million, respectively, recorded for potential obsolete, expiring or unsalable product.
Property and Equipment, net	'
	Property and Equipment, net
	Property and equipment is comprised of furniture, equipment, leasehold improvements, information technology hardware and software and is recorded at cost. At the time the property and equipment is ready for its intended use, it is depreciated on a straight-line basis over the estimated useful lives of the assets (generally three to five years). Leasehold improvements are amortized on a straight-line basis over the shorter of the lease term or the estimated useful lives of the improvements.
Capitalization of Software Costs	'
	Capitalization of Software Costs
	The Company capitalizes certain significant costs incurred in the acquisition and development of software for internal use, including the costs of the software, materials, consultants, and payroll and payroll-related costs for employees during the application development stage. Costs incurred prior to the application development stage, costs incurred once the application is substantially complete and ready for its intended use, and other costs not qualifying for capitalization, including training and maintenance costs, are charged to expense.
Goodwill and Intangible Assets, net	'
	Goodwill and Intangible Assets, net
	Additions to goodwill and intangible assets, net are derived at the time of a business acquisition, in which the Company assigns the total consideration transferred to the acquired assets based on each asset’s fair value and any residual amount becomes goodwill, an indefinite life intangible asset. Intangible assets, net, which include a license for the right to commercialize the INTERCEPT Blood System in Asia, are subject to ratable amortization over the estimated useful life of ten years. The amortization of the Company’s intangible assets, net, is recorded in “Amortization of intangible assets” on the Company’s condensed consolidated statements of operations. Goodwill is not amortized but instead is subject to an impairment test performed on an annual basis, or more frequently if events or changes in circumstances indicate that goodwill may be impaired. Such impairment analysis is performed on August 31 of each fiscal year, or more frequently if indicators of impairment exist. The test for goodwill impairment may be assessed using qualitative factors to determine whether it is more likely than not that the fair value of a reporting unit is less than the carrying amount. If the Company determines that it is more likely than not that the fair value of a reporting unit is less than the carrying amount, the Company must then proceed with performing the quantitative two-step process to test goodwill for impairment; otherwise, goodwill is not considered impaired and no further testing is warranted. The Company may choose not to perform the qualitative assessment to test goodwill for impairment and proceed directly to the quantitative two-step process; however, the Company may revert to the qualitative assessment to test goodwill for impairment in any subsequent period. The first step of the two-step process compares the fair value of each reporting unit with its respective carrying amount, including goodwill. The Company has determined that it operates in one segment and has one reporting unit and estimates the fair value of its one reporting unit using the enterprise approach under which it considers the quoted market capitalization of the Company as reported on the Nasdaq Global Market. The Company considers quoted market prices that are available in active markets to be the best evidence of fair value. The Company also considers other factors, which include future forecasted results, the economic environment and overall market conditions. If the fair value of the reporting unit exceeds its carrying amount, goodwill of the reporting unit is not considered impaired and, therefore, the second step of the impairment test is unnecessary. The second step of the two-step process, which is used to measure the amount of impairment loss, compares the implied fair value of each reporting unit’s goodwill with the respective carrying amount of that goodwill. If the carrying amount of the reporting unit’s goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized in an amount equal to that excess.
	The Company performs an impairment test on its intangible assets, in accordance ASC Topic 360-10, “Property, Plant and Equipment,” if certain events or changes in circumstances occur which indicate that the carrying amounts of its intangible assets may not be recoverable. If the intangible assets are not recoverable, an impairment loss would be recognized by the Company based on the excess amount of the carrying value of the intangible assets over its fair value. For further details regarding the impairment analysis, reference is made to the section below under “Long-lived Assets.” Also, see Note 5 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s impairment analysis and the valuation of goodwill and intangible assets, net.
Long-lived Assets	'
	Long-lived Assets
	The Company evaluates its long-lived assets for impairment by continually monitoring events and changes in circumstances that could indicate carrying amounts of its long-lived assets may not be recoverable. When such events or changes in circumstances occur, the Company assesses recoverability by determining whether the carrying value of such assets will be recovered through the undiscounted expected future cash flows. If the expected undiscounted future cash flows are less than the carrying amount of these assets, the Company then measures the amount of the impairment loss based on the excess of the carrying amount over the fair value of the assets. The Company did not recognize impairment charges related to its long-lived assets during the three months ended March 31, 2014, and 2013.
Foreign Currency Remeasurement	'
	Foreign Currency Remeasurement
	The functional currency of the Company’s foreign subsidiary is the United States dollar. Monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using the exchange rates at the balance sheet date. Non-monetary assets and liabilities denominated in foreign currencies are remeasured in United States dollars using historical exchange rates. Revenues and expenses are remeasured using average exchange rates prevailing during the period. Remeasurements are recorded in the Company’s condensed consolidated statements of operations. The Company recorded foreign currency gains (losses) of less than $0.1 million and $(0.1) million during the three months ended March 31, 2014, and 2013, respectively.
Stock-Based Compensation	'
	Stock-Based Compensation
	The Company accounts for stock-based compensation in accordance with ASC Topic 718, “Compensation – Stock Compensation.” Stock-based compensation expense is measured at the grant-date based on the fair value of the award and is recognized as expense on a straight-line basis over the requisite service period, which is the vesting period, and is adjusted for estimated forfeitures. To the extent that stock options contain performance criteria for vesting, stock-based compensation is recognized once the performance criteria are probable of being achieved.
	For stock-based awards issued to non-employees, the Company follows ASC Topic 505-50, “Equity Based Payment to Non-Employees” and considers the measurement date at which the fair value of the stock-based award is measured to be the earlier of (i) the date at which a commitment for performance by the grantee to earn the equity instrument is reached or (ii) the date at which the grantee’s performance is complete. The Company recognizes stock-based compensation expense for the fair value of the vested portion of the non-employee stock-based awards in its condensed consolidated statements of operations.
	See Note 11 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s stock-based compensation assumptions and expenses.
Warrant Liability	'
	Warrant Liability
	In August 2009 and November 2010, the Company issued warrants to purchase an aggregate of 2.4 million and 3.7 million shares of common stock, respectively. The material terms of the warrants were identical under each issuance except for the exercise price, date issued and expiration date. The Company classifies the warrants as a liability on its condensed consolidated balance sheets as the warrants contain certain material terms which require the Company (or its successor) to purchase the warrants for cash in an amount equal to the value of the unexercised portion of the warrants (as determined in accordance with the Black-Scholes option pricing model) in connection with certain change of control transactions. In addition, the Company may also be required to pay cash to a warrant holder under certain circumstances if the Company is unable to timely deliver the shares acquired upon warrant exercise to such holder.
	The fair value of these outstanding warrants is calculated using the binomial-lattice option-pricing model and is adjusted accordingly at each reporting period. The binomial-lattice option-pricing model requires that the Company uses significant assumptions and judgment to determine appropriate inputs to the model. Some of the assumptions that the Company relies on include the probability of a change of control occurring, the volatility of the Company’s stock over the life of the warrant and assumptions and inputs used to value the warrants under the Black-Scholes model should a change of control occur.
	Changes resulting from the revaluation of warrants to fair value are recorded in “Revaluation of warrant liability” on the condensed consolidated statements of operations. Upon the exercise or modification to remove the provisions which require the warrants to be treated as a liability, the fair value of the warrants will be reclassified from a liability to stockholders’ equity on the Company’s condensed consolidated balance sheets and no further adjustment to the fair value would be made in subsequent periods.
	See Note 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of warrant liability.
Income Taxes	'
	Income Taxes
	The Company accounts for income taxes using an asset and liability approach in accordance with ASC Topic 740 “Accounting for Income Taxes.” Under this method, deferred tax assets and liabilities are determined based on differences between the financial reporting and tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. ASC Topic 740 requires derecognition of tax positions that do not have a greater than 50% likelihood of being recognized upon review by a taxing authority having full knowledge of all relevant information. Use of a valuation allowance as described in ASC Topic 740 is not an appropriate substitute for the derecognition of a tax position. The Company recognizes accrued interest and penalties related to unrecognized tax benefits in its income tax expense. To date, the Company has not recognized any interest and penalties in its condensed consolidated statements of operations, nor has its accrued for or made payments for interest and penalties. The Company continues to carry a full valuation allowance on all of its deferred tax assets. Although the Company believes it more likely than not that a taxing authority would agree with its current tax positions, there can be no assurance that the tax positions the Company has taken will be substantiated by a taxing authority if reviewed. The Company’s tax years 1998 through 2013 remain subject to examination by the taxing jurisdictions due to unutilized net operating losses and research credits.
Net Income (Loss) Per Share	'
	Net Income (Loss) Per Share
	Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of common shares outstanding for the period. Diluted net income (loss) per share gives effect to all potentially dilutive common shares outstanding for the period. The potentially dilutive securities include stock options, employee stock purchase plan rights, warrants and restricted stock units, which are calculated using the treasury stock method. Diluted net income (loss) per share also gives effect to potential adjustments to the numerator for changes resulting from the revaluation of warrants to fair value for the period, even if the Company is in a net loss position, if the effect would result in more dilution.
	Certain potential dilutive securities were excluded from the dilution calculation for the three months ended March 31, 2014, and 2013, as their inclusion would have been anti-dilutive.
	The following table sets forth the reconciliation of the numerator and denominator used in the computation of basic and diluted net income (loss) per share for the three months ended March 31, 2014, and 2013 (in thousands, except per share amounts):
		Three Months Ended
		March 31,
		2014			2013
	Numerator for Basic and Diluted:
	Net loss used for basic calculation	$	(225	)	$	(10,252	)
	Effect of revaluation of warrant liability		(9,034	)		0
	Adjusted net loss used for diluted calculation	$	(9,259	)	$	(10,252	)
	Denominator:
	Basic weighted average number of shares outstanding		72,088			59,730
	Effect of dilutive potential shares		3,070			0
	Diluted weighted average number of shares outstanding		75,158			59,730
	Net loss per share:
	Basic	$	(0.00	)	$	(0.17	)
	Diluted	$	(0.12	)	$	(0.17	)
	The table below presents shares underlying stock options, employee stock purchase plan rights, warrants and restricted stock units that are excluded from the calculation of the weighted average number of shares outstanding used for the calculation of diluted net loss per share. These are excluded from the calculation due to their anti-dilutive effect for the three months ended March 31, 2014 and 2013 (shares in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Weighted average number of anti-dilutive potential shares		16,901			15,531
Guarantee and Indemnification Arrangements	'
	Guarantee and Indemnification Arrangements
	The Company recognizes the fair value for guarantee and indemnification arrangements issued or modified by the Company after December 31, 2002. In addition, the Company monitors the conditions that are subject to the guarantees and indemnifications in order to identify if a loss has occurred. If the Company determines it is probable that a loss has occurred, then any such estimable loss would be recognized under those guarantees and indemnifications. Some of the agreements that the Company is a party to contain provisions that indemnify the counter party from damages and costs resulting from claims that the Company’s technology infringes the intellectual property rights of a third party or claims that the sale or use of the Company’s products have caused personal injury or other damage or loss. The Company has not received any such requests for indemnification under these provisions and has not been required to make material payments pursuant to these provisions.
	The Company generally provides for a one-year warranty on certain of its INTERCEPT blood-safety products covering defects in materials and workmanship. The Company accrues costs associated with warranty obligations when claims become known and are estimable.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The Company applies the provisions of fair value relating to its financial assets and liabilities. The carrying amounts of accounts receivables, accounts payable, and other accrued liabilities approximate their fair value due to the relative short-term maturities. Based on the borrowing rates currently available to the Company for loans with similar terms, the Company believes the fair value of its debt approximates its carrying amounts. The Company measures and records certain financial assets and liabilities at fair value on a recurring basis, including its available-for-sale securities and warrant liability. The Company classifies instruments within Level 1 if quoted prices are available in active markets for identical assets, which include the Company’s cash accounts and money market funds. The Company classifies instruments in Level 2 if the instruments are valued using observable inputs to quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. These instruments include the Company’s available-for-sale securities related to corporate debt and United States government agency securities. The available-for-sale securities are held by a custodian who obtains investment prices from a third party pricing provider that uses standard inputs (observable in the market) to models which vary by asset class. The Company classifies instruments in Level 3 if one or more significant inputs or significant value drivers are unobservable, which include its warrant liability. The Company assesses any transfers among fair value measurement levels at the end of each reporting period.
	See Note 2 and 10 in the Notes to Unaudited Condensed Consolidated Financial Statements for further information regarding the Company’s valuation of financial instruments.
New Accounting Pronouncements	'
	New Accounting Pronouncements
	There have been no new accounting pronouncements issued during the three months ending March 31, 2014 that are of significance, or potential significance, to the Company.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2014
Computation of Basic and Diluted Net Loss per Share	'
	The following table sets forth the reconciliation of the numerator and denominator used in the computation of basic and diluted net income (loss) per share for the three months ended March 31, 2014, and 2013 (in thousands, except per share amounts):
		Three Months Ended
		March 31,
		2014			2013
	Numerator for Basic and Diluted:
	Net loss used for basic calculation	$	(225	)	$	(10,252	)
	Effect of revaluation of warrant liability		(9,034	)		0
	Adjusted net loss used for diluted calculation	$	(9,259	)	$	(10,252	)
	Denominator:
	Basic weighted average number of shares outstanding		72,088			59,730
	Effect of dilutive potential shares		3,070			0
	Diluted weighted average number of shares outstanding		75,158			59,730
	Net loss per share:
	Basic	$	(0.00	)	$	(0.17	)
	Diluted	$	(0.12	)	$	(0.17	)
Anti-Dilutive Effect of Common Shares	'
	The table below presents shares underlying stock options, employee stock purchase plan rights, warrants and restricted stock units that are excluded from the calculation of the weighted average number of shares outstanding used for the calculation of diluted net loss per share. These are excluded from the calculation due to their anti-dilutive effect for the three months ended March 31, 2014 and 2013 (shares in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Weighted average number of anti-dilutive potential shares		16,901			15,531

Fair_Value_on_Financial_Instru1

Fair Value on Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value of Financial Assets and Liabilities	'
	The fair values of the Company’s financial assets and liabilities were determined using the following inputs at March 31, 2014 (in thousands):
			Total			Quoted		Significant		Significant
						Prices in		Other		Unobservable
						Active		Observable		Inputs
						Markets for		Inputs		(Level 3)
						Identical		(Level 2)
						Assets
						(Level 1)
	Money market funds (1)		$	9,648		$	9,648	$	0	$	0
	Corporate debt securities (2)			20,251			0		20,251		0
	United States government agency securities (2)			4,012			0		4,012		0
	Total financial assets		$	33,911		$	9,648	$	24,263	$	0
	Warrant liability (3)		$	11,356		$	0	$	0	$	11,356
	Total financial liabilities		$	11,356		$	0	$	0	$	11,356
	-1	Included in cash and cash equivalents on the Company’s condensed consolidated balance sheets.
	-2	Included in short-term investments on the Company’s condensed consolidated balance sheets.
	-3	Included in current liabilities on the Company’s condensed consolidated balance sheets.
	The fair values of the Company’s financial assets and liabilities were determined using the following inputs at December 31, 2013 (in thousands):
			Total			Quoted		Significant		Significant
						Prices in		Other		Unobservable
						Active		Observable		Inputs
						Markets for		Inputs		(Level 3)
						Identical		(Level 2)
						Assets
						(Level 1)
	Money market funds (1)		$	8,650		$	8,650	$	0	$	0
	Corporate debt securities (2)			23,173			0		23,173		0
	United States government agency securities (2)			5,018			0		5,018		0
	Total financial assets		$	36,841		$	8,650	$	28,191	$	0
	Warrant liability (3)		$	20,390		$	0	$	0	$	20,390
	Total financial liabilities		$	20,390		$	0	$	0	$	20,390
	-1	Included in cash and cash equivalents on the Company’s condensed consolidated balance sheets.
	-2	Included in short-term investments on the Company’s condensed consolidated balance sheets.
	-3	Included in current liabilities on the Company’s condensed consolidated balance sheets.
Reconciliation of Fair Value Measurement on Liabilities Using Significant Unobservable Inputs	'
	A reconciliation of the beginning and ending balances for warrant liability using significant unobservable inputs (Level 3) from December 31, 2013 to March 31, 2014 was as follows (in thousands):
	Balance at December 31, 2013		$	20,390
	Decrease in fair value of warrants			(9,034	)
	Balance at March 31, 2014		$	11,356

Availableforsale_Securities_Ta

Available-for-sale Securities (Tables)	3 Months Ended
	Mar. 31, 2014
Summary of Available for Sale Securities	'
	The following is a summary of available-for-sale securities at March 31, 2014 (in thousands):
		March 31, 2014
		Carrying Value		Gross			Fair Value
				Unrealized Gain
	Money market funds	$	9,648	$	0		$	9,648
	Corporate debt securities		20,243		8			20,251
	United States government agency securities		4,012		0			4,012
	Total available-for-sale securities	$	33,903	$	8		$	33,911
	The following is a summary of available-for-sale securities at December 31, 2013 (in thousands):
		December 31, 2013
		Carrying Value		Gross			Fair Value
				Unrealized Gain
	Money market funds	$	8,650	$	0		$	8,650
	Corporate debt securities		23,165		8			23,173
	United States government agency securities		5,019		(1	)		5,018
	Total available-for-sale securities	$	36,834	$	7		$	36,841
Available for Sale Securities by Original Contractual Maturity	'
	Available-for-sale securities at March 31, 2014 and December 31, 2013 consisted of the following by original contractual maturity (in thousands):
		March 31, 2014					December 31, 2013
		Carrying Value		Fair Value			Carrying Value		Fair Value
	Due in one year or less	$	33,903	$	33,911		$	30,700	$	30,701
	Due greater than one year and less than three years		0		0			6,134		6,140
	Total cash equivalents and short-term investments	$	33,903	$	33,911		$	36,834	$	36,841

Inventories_Tables

Inventories (Tables)	3 Months Ended
	Mar. 31, 2014
Inventories	'
	Inventories at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Work-in-process	$	2,142	$	4,863
	Finished goods		9,165		8,200
	Total inventories	$	11,307	$	13,063

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets, net (Tables)	3 Months Ended
	Mar. 31, 2014
Summary of Intangible Assets	'
	The following is a summary of intangible assets, net at March 31, 2014 (in thousands):
		March 31, 2014
		Gross		Accumulated			Net
		Carrying		Amortization			Carrying
		Amount					Amount
	Acquisition-related intangible assets:
	Reacquired license - INTERCEPT Asia	$	2,017	$	(723	)	$	1,294
	Total intangible assets	$	2,017	$	(723	)	$	1,294
	The following is a summary of intangible assets, net at December 31, 2013 (in thousands):
		December 31, 2013
		Gross		Accumulated			Net
		Carrying		Amortization			Carrying
		Amount					Amount
	Acquisition-related intangible assets:
	Reacquired license - INTERCEPT Asia	$	2,017	$	(673	)	$	1,344
	Total intangible assets	$	2,017	$	(673	)	$	1,344

Accrued_Liabilities_Tables

Accrued Liabilities (Tables)	3 Months Ended
	Mar. 31, 2014
Accrued Liabilities	'
	Accrued liabilities at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,		December 31,
		2014		2013
	Accrued compensation and related costs	$	1,899	$	2,527
	Accrued inventory costs		2,534		3,553
	Accrued professional services		2,995		2,722
	Other accrued expenses		1,410		1,011
	Total accrued liabilities	$	8,838	$	9,813

Debt_Tables

Debt (Tables)	3 Months Ended
	Mar. 31, 2014
Debt	'
	Debt at March 31, 2014 consisted of the following (in thousands):
		March 31, 2014
		Principal			Unamortized		Total
					Discount
	Comerica - Revolving Line of Credit, due 2014	$	3,268		$	0	$	3,268
	Less: debt - current		(3,268	)		0		(3,268	)
	Debt - non-current	$	0		$	0	$	0
	Debt at December 31, 2013 consisted of the following (in thousands):
		December 31, 2013
		Principal			Unamortized		Total
					Discount
	Comerica - Revolving Line of Credit, due 2014	$	3,366		$	0	$	3,366
	Less: debt - current		(3,366	)		0		(3,366	)
	Debt - non-current	$	0		$	0	$	0

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value of Warrants	'
	The fair value of the warrants at March 31, 2014 and December 31, 2013 consisted of the following (in thousands):
		March 31,			December 31,
		2014			2013
	2009 Warrants	$	4,637		$	8,542
	2010 Warrants		6,719			11,848
	Total warrant liability	$	11,356		$	20,390
Fair Value Assumptions of Warrants	'
	The fair value of the Company’s warrants was based on using the binomial-lattice option valuation model and using the following assumptions at March 31, 2014 and December 31, 2013:
		March 31,			December 31,
		2014			2013
	2009 Warrants:
	Expected term (in years)		0.4			0.65
	Estimated volatility		52	%		45	%
	Risk-free interest rate		0.07	%		0.1	%
	Expected dividend yield		0	%		0	%
	2010 Warrants:
	Expected term (in years)		1.61			1.86
	Estimated volatility		45	%		41	%
	Risk-free interest rate		0.44	%		0.38	%
	Expected dividend yield		0	%		0	%

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2014
Activity Under Equity Incentive Plans Related to Stock Options	'
	Activity under the Company’s equity incentive plans related to stock options is set forth below (in thousands except per share amounts):
		Number of			Weighted
		Options			Average
		Outstanding			Exercise
					Price per
					Share
	Balances at December 31, 2013		10,405		$	3.46
	Granted		2,347			6.2
	Forfeited		(36	)		4.49
	Expired		(30	)		9.78
	Exercised		(478	)		2.65
	Balances at March 31, 2014		12,208		$	4
Recognition of Stock-Based Compensation Expense	'
	Stock-based compensation recognized on the Company’s condensed consolidated statements of operations for the three months ended March 31, 2014 and 2013, was as follows (in thousands):
		Three Months Ended
		March 31,
		2014			2013
	Stock-based compensation expense by caption:
	Research and development	$	183		$	87
	Selling, general and administrative		762			626
	Total stock-based compensation expense	$	945		$	713

Segment_Customer_and_Geographi1

Segment, Customer and Geographic Information (Tables)	3 Months Ended
	Mar. 31, 2014
Customers that Accounted for More Than Ten Percent of Total Product Revenue	'
	The Company had the following significant customers that accounted for more than 10% of the Company’s total product revenue, all of which operate in a country outside of the United States, during the three months ended March 31, 2014 and 2013 (in percentages):
			Three Months Ended
			March 31,
			2014			2013
	Etablissement Francais du Sang			23	%		16	%
	Movaco, S.A.			19	%		19	%
	Delrus Inc.				*		19	%
	*	Represents an amount less than 10% of product revenue.

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended						3 Months Ended	12 Months Ended	3 Months Ended
Share data in Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013		Aug. 31, 2009	Nov. 30, 2010	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2014
	Segment		Customer		2009 Unit Offering	2010 Unit Offering	Trade Accounts Receivable	Trade Accounts Receivable	Minimum	Maximum
	Customer
Summary Of Significant Accounting Policies [Line Items]	'	'	'		'	'	'	'	'	'
Deferred revenue	$279,000	'	$181,000	[1]	'	'	'	'	'	'
Number of major customers representing outstanding trade receivables	3	'	2		'	'	'	'	'	'
Cumulative outstanding trade receivables percentage by major customers	'	'	'		'	'	65.00%	55.00%	'	'
Life of inventory	'2 years	'	'		'	'	'	'	'	'
Protracted length of inventory	'1 year	'	'		'	'	'	'	'	'
Inventory valuation reserves	300,000	'	400,000		'	'	'	'	'	'
Estimated useful life of property and equipment	'	'	'		'	'	'	'	'3 years	'5 years
Estimated useful life of intangible assets	'10 years	'	'		'	'	'	'	'	'
Number of operating segments	1	'	'		'	'	'	'	'	'
Number of reportable segments	1	'	'		'	'	'	'	'	'
Impairment charges on long-lived assets	0	0	'		'	'	'	'	'	'
Foreign exchange gain (loss)	$100,000	($100,000)	'		'	'	'	'	'	'
Warrants to purchase an aggregate shares of common stock	'	'	'		2.4	3.7	'	'	'	'
Derecognition of tax positions, Maximum	'	'	'		'	'	'	'	'	50.00%
Company's tax years subject to examination by the taxing jurisdictions	'	'	'		'	'	'	'	'1998	'2013
Period of warranty	'1 year	'	'		'	'	'	'	'	'
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Reconciliation_of_Numerator_an

Reconciliation of Numerator and Denominator Used in Computation of Basic and Diluted Net Income Loss per Share (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Numerator for Basic and Diluted:	'	'
Net loss used for basic calculation	($225)	($10,252)
Effect of revaluation of warrant liability	-9,034	0
Adjusted net loss used for diluted calculation	($9,259)	($10,252)
Denominator:	'	'
Basic weighted average number of shares outstanding	72,088	59,730
Effect of dilutive potential shares	3,070	0
Diluted weighted average number of shares outstanding	75,158	59,730
Net loss per share:	'	'
Basic	$0	($0.17)
Diluted	($0.12)	($0.17)

Shares_Underlying_Stock_Option

Shares Underlying Stock Options, Employee Stock Purchase Plan Rights, Warrants and Restricted Stock Units Excluded from Calculation of Weighted Average Number of Shares Outstanding used for Calculation of Diluted Net Income Loss Per Share (Detail)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Weighted average number of anti-dilutive potential shares	16,901	15,531

Fair_Value_on_Financial_Assets

Fair Value on Financial Assets and Liabilities (Detail) (USD $)	Mar. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Fair value of financial assets and liabilities	'		'
Total financial assets	$33,911		$36,841
Total financial liabilities	11,356		20,390
Money market funds	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	9,648	[1]	8,650	[1]
Corporate debt securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	20,251	[2]	23,173	[2]
United States government agency securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	4,012	[2]	5,018	[2]
Warrant Liability	'		'
Fair value of financial assets and liabilities	'		'
Total financial liabilities	11,356	[3]	20,390	[3]
Quoted Prices in Active Markets for Identical Assets (Level 1)	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	9,648		8,650
Total financial liabilities	0		0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market funds	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	9,648	[1]	8,650	[1]
Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[2]	0	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) | United States government agency securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[2]	0	[2]
Quoted Prices in Active Markets for Identical Assets (Level 1) | Warrant Liability	'		'
Fair value of financial assets and liabilities	'		'
Total financial liabilities	0	[3]	0	[3]
Significant Other Observable Inputs (Level 2)	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	24,263		28,191
Total financial liabilities	0		0
Significant Other Observable Inputs (Level 2) | Money market funds	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2) | Corporate debt securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	20,251	[2]	23,173	[2]
Significant Other Observable Inputs (Level 2) | United States government agency securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	4,012	[2]	5,018	[2]
Significant Other Observable Inputs (Level 2) | Warrant Liability	'		'
Fair value of financial assets and liabilities	'		'
Total financial liabilities	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3)	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0		0
Total financial liabilities	11,356		20,390
Significant Unobservable Inputs (Level 3) | Money market funds	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[1]	0	[1]
Significant Unobservable Inputs (Level 3) | Corporate debt securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) | United States government agency securities	'		'
Fair value of financial assets and liabilities	'		'
Total financial assets	0	[2]	0	[2]
Significant Unobservable Inputs (Level 3) | Warrant Liability	'		'
Fair value of financial assets and liabilities	'		'
Total financial liabilities	$11,356	[3]	$20,390	[3]
[1]	Included in cash and cash equivalents on the Company's condensed consolidated balance sheets.
[2]	Included in short-term investments on the Company's condensed consolidated balance sheets.
[3]	Included in current liabilities on the Company's condensed consolidated balance sheets.

Reconciliation_of_Beginning_an

Reconciliation of Beginning and Ending Balances for Warrant Liability Using Significant Unobservable Inputs (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]	'
Beginning balance	$20,390
Decrease in fair value of warrants	-9,034
Ending balance	$11,356

Summary_of_Available_for_Sale_

Summary of Available for Sale Securities (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Carrying Value	$33,903	$36,834
Gross Unrealized Gain	8	7
Fair Value	33,911	36,841
Money market funds	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Carrying Value	9,648	8,650
Gross Unrealized Gain	0	0
Fair Value	9,648	8,650
Corporate debt securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Carrying Value	20,243	23,165
Gross Unrealized Gain	8	8
Fair Value	20,251	23,173
United States government agency securities	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Carrying Value	4,012	5,019
Gross Unrealized Gain	0	-1
Fair Value	$4,012	$5,018

Available_for_Sale_Securities_

Available for Sale Securities by Original Contractual Maturity (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Due in one year or less, carrying value	$33,903	$30,700
Due greater than one year and less than three years, carrying value	0	6,134
Total cash equivalents and short-term investments, carrying value	33,903	36,834
Due in one year or less, fair value	33,911	30,701
Due greater than one year and less than three years, fair value	0	6,140
Total cash equivalents and short-term investments, fair value	$33,911	$36,841

Inventories_Detail

Inventories (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventory [Line Items]	'	'
Work-in-process	$2,142	$4,863
Finished goods	9,165	8,200
Total inventories	$11,307	$13,063

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets Net - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]	'	'
Disposal or recognition of additional goodwill	$0	'
Impairment charges on goodwill	0	'
Amortization of intangible assets	50,000	50,000
Impairment charges recognized related to the acquired intangible assets	0	0
Annual amortization expense of the intangible assets, 2014 (remaining nine months)	150,000	'
Annual amortization expense of the intangible assets, 2015	200,000	'
Annual amortization expense of the intangible assets, 2016	200,000	'
Annual amortization expense of the intangible assets, 2017	200,000	'
Annual amortization expense of the intangible assets, 2018	200,000	'
Annual amortization expense of the intangible assets, 2019	200,000	'
Annual amortization expense of the intangible assets, 2020	$100,000	'

Summary_of_Intangible_Assets_N

Summary of Intangible Assets Net (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Acquired Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$2,017	$2,017
Accumulated Amortization	-723	-673
Net Carrying Amount	1,294	1,344
Reacquired license - INTERCEPT Asia	'	'
Acquired Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	2,017	2,017
Accumulated Amortization	-723	-673
Net Carrying Amount	$1,294	$1,344

LongTerm_Investments_Additiona

Long-Term Investments - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014
Investment [Line Items]	'
Eligibility to receive a royalty fee	1.00%
Royalty income, nonoperating	$0
Carrying value of investment	$0
Maximum	'
Investment [Line Items]	'
Ownership percentage under Cost Method for Investments	3.00%

Accrued_Liabilities_Detail

Accrued Liabilities (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Accrued Liabilities [Line Items]	'	'
Accrued compensation and related costs	$1,899	$2,527
Accrued inventory costs	2,534	3,553
Accrued professional services	2,995	2,722
Other accrued expenses	1,410	1,011
Total accrued liabilities	$8,838	$9,813	[1]
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Debt_Detail

Debt (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'	'
Less: debt - current, Principal	($3,268)	($3,366)
Less: debt - current, Unamortized Discount	0	0
Less: debt - current	-3,268	-3,366	[1]
Debt - non-current, Principal	0	0
Debt - non-current, Unamortized Discount	0	0
Debt - non-current	0	0
Comerica - Revolving Line of Credit, due 2014	'	'
Debt Instrument [Line Items]	'	'
Total debt, Principal	3,268	3,366
Total debt, Unamortized amount	0	0
Total debt	$3,268	$3,366
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Debt_Additional_Information_De

Debt - Additional Information (Detail) (USD $)	Mar. 31, 2014	Jun. 30, 2012	Jun. 30, 2012	Mar. 31, 2014	Mar. 31, 2014	Dec. 31, 2013	Jun. 30, 2012	Apr. 30, 2013	Sep. 30, 2011	Jun. 30, 2012
In Millions, unless otherwise specified		Securities Pledged as Collateral	Comerica - Growth Capital Facility	Compliance With Covenants	Revolving Credit Facility	Revolving Credit Facility	Revolving Credit Facility	Capital Loan	Capital Loan	Capital Loan
					Comerica - Growth Capital Facility	Comerica - Growth Capital Facility	Comerica - Growth Capital Facility	Comerica - Growth Capital Facility	Comerica - Growth Capital Facility	Comerica - Growth Capital Facility
Line of Credit Facility [Line Items]	'	'	'	'	'	'	'	'	'	'
Principal and interest payments on debt	$3.30	'	'	'	'	'	'	'	'	'
Amended Credit Agreement	'	'	12	'	'	'	7	'	5	'
Growth capital loan from amended Credit Agreement	'	'	'	'	'	'	'	'	'	5
Percentage of investments made in subsidiary	'	35.00%	'	'	'	'	'	'	'	'
Principal and interest payments	'	'	'	'	'	'	'	'	'The Growth Capital Loan was scheduled to mature on September 30, 2015 and bore a fixed interest rate of 6.37%, with interest-only payments due for the first twelve months, followed by equal principal and interest payments for the remaining 36 months.	'
Maturity period	'	'	'	'	30-Jun-14	'	'	'	30-Sep-15	'
Fixed interest rate	'	'	'	'	'	'	'	'	6.37%	'
Interest Only payments Period	'	'	'	'	'	'	'	'	'12 months	'
Principal and interest payments	'	'	'	'	'	'	'	'	'36 months	'
Final payment fee for early repayment of credit facility	'	'	'	'	'	'	'	0.05	'	'
Repayment of credit facility	'	'	'	'	'	'	'	4.2	'	'
Amount under RLOC available to the Company	'	'	'	'	80.00%	'	'	'	'	'
Outstanding amounts	'	'	'	'	3.3	3.4	'	'	'	'
Lender's prime rate plus 1.50%	'	'	'	'	'Lender's prime rate plus 1.50%	'	'	'	'	'
Margin rate	'	'	'	'	1.50%	'	'	'	'	'
Floating rate of interest	'	'	'	'	4.75%	4.75%	'	'	'	'
Minimum cash balance	'	'	'	$2.50	'	'	'	'	'	'
Minimum revenues levels percentage	'	'	'	75.00%	'	'	'	'	'	'

Commitments_and_Contingencies_

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2010
Commitments and Contingencies Disclosure [Line Items]	'	'
Minimum term of non-cancellable operating leases	'1 year	'
Expiration of non-cancellable operating leases maximum year	'2019	'
Financing for leasehold improvement	'	$1,100,000
Outstanding liability related to leasehold improvements	700,000	'
Leasehold Improvements reflected in Accrued liabilities	100,000	'
Leasehold Improvements reflected in Other non-current liabilities	600,000	'
Additional Concord Lease	'	'
Commitments and Contingencies Disclosure [Line Items]	'	'
Early termination of non-cancellable operating leases minimum period	'2015-01	'
Initial term of operating lease	'2 years	'
Number of renewal options	4	'
Renewal period of operating lease	'2 years	'
Lease commencement date	1-Aug-13	'
Future rent payment, 2014	115,776	'
Future rent payment, 2015	$90,048	'

Stockholders_Equity_Additional

Stockholders Equity - Additional Information (Detail) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

1 Months Ended

12 Months Ended

3 Months Ended

3 Months Ended

12 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2013

Mar. 19, 2013

Mar. 31, 2013

Aug. 31, 2009

Nov. 30, 2010

Aug. 31, 2009

Nov. 30, 2010

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Dec. 31, 2013

IPO

IPO

IPO

2009 Unit Offering

2010 Unit Offering

Warrant

Warrant

Warrant

Stockholder Rights Plan

Sales Agreement

Sales Agreement

Sales Agreement

Sales Agreement

Overallotment Option

2009 Unit Offering

2010 Unit Offering

2010 Unit Offering

Mlv

Mlv

Cantor

Cantor

Maximum

Stockholders Equity Note [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Warrants to purchase an aggregate shares of common stock

'

'

'

'

'

'

2,400,000

3,700,000

'

'

'

'

'

'

'

'

Warrant exercise price

'

'

'

'

'

'

2.9

3.2

'

'

'

'

'

'

'

'

Exercisable period

'

'

'

'

'

'

'

'

'5 years

'5 years

'

'

'

'

'

'

Warrant liability

$11,356,000

'

$20,390,000

[1]

'

'

'

'

'

$2,800,000

$5,800,000

'

'

'

'

'

'

Risk-free interest rate

'

'

'

'

'

'

'

'

2.48%

1.23%

'

'

'

'

'

'

Expected term (in years)

'

'

'

'

'

'

'

'

'5 years

'5 years

'

'

'

'

'

'

Expected dividend yield

'

'

'

'

'

'

'

'

0.00%

0.00%

'

'

'

'

'

'

Estimated volatility

'

'

'

'

'

'

'

'

77.00%

85.00%

'

'

'

'

'

'

Net proceeds from underwritten public offering

'

'

'

'

'

'

'

'

'

19,700,000

'

'

'

'

'

'

Payment for underwriting discounts and commissions and stock issuance cost

'

'

'

500,000

'

'

'

'

'

1,300,000

'

'

'

'

'

'

Number of units sold in underwritten public offering

'

'

'

'

'

'

'

'

'

7,400,000

'

'

'

'

'

'

Number of common stock in each unit

'

'

'

'

'

'

'

'

'

1

'

'

'

'

'

'

Number of common stock shares purchasable with each warrant

'

'

'

'

'

'

'

'

'

0.5

'

'

'

'

'

'

Units issued, price per unit

'

'

'

'

'

'

'

'

'

$2.85

'

'

'

'

'

'

Common stock, number of shares issued

'

'

'

8,300,000

'

1,300,000

'

'

'

7,400,000

'

'

'

'

0

5,400,000

Warrants exercisable date

'

'

'

'

'

'

'

'

'

15-May-11

'

'

'

'

'

'

Gain (loss) from revaluation of warrant liability

9,034,000

-5,073,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Warrants exercised

'

'

'

'

'

'

'

'

'

'

186,586

'

'

'

'

'

Maximum common stock offering price

'

'

'

'

'

'

'

'

'

'

'

'

20,000,000

'

70,000,000

'

Common stock available for sale

'

'

'

'

'

'

'

'

'

'

'

'

'

100,000

41,500,000

'

Percentage of proceeds payable as compensation to underwriter

'

'

'

'

'

'

'

'

'

'

'

'

'

'

2.00%

'

Proceeds from common stock sold

31,000

51,502,000

'

38,000,000

'

'

'

'

'

'

'

'

'

'

0

23,500,000

Common stock, price per share

'

'

'

'

$4.20

'

'

'

'

'

'

'

'

'

'

'

Gross proceeds from public offering

'

'

'

40,300,000

'

'

'

'

'

'

'

'

'

'

'

'

Underwriter's discount

'

'

'

$1,800,000

'

'

'

'

'

'

'

'

'

'

'

'

Minimum percentage of common stock acquired by stockholders

'

'

'

'

'

'

'

'

'

'

'

15.00%

'

'

'

'

Designated preferred stock for future issuance

'

'

'

'

'

'

'

'

'

'

'

250,000

'

'

'

'

[1]

The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Fair_Value_of_Warrants_Detail

Fair Value of Warrants (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Class of Warrant or Right [Line Items]	'	'
Warrant liability	$11,356	$20,390	[1]
2009 Warrants	'	'
Class of Warrant or Right [Line Items]	'	'
Warrant liability	4,637	8,542
2010 Warrants	'	'
Class of Warrant or Right [Line Items]	'	'
Warrant liability	$6,719	$11,848
[1]	The financial information in this column was derived from audited financial statements included in the Company's 2013 Annual Report on Form 10-K.

Fair_Value_of_Warrants_Using_V

Fair Value of Warrants Using Valuation Model (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
2009 Warrants	'	'
Class of Warrant or Right [Line Items]	'	'
Expected term (in years)	'4 months 24 days	'7 months 24 days
Estimated volatility	52.00%	45.00%
Risk-free interest rate	0.07%	0.10%
Expected dividend yield	0.00%	0.00%
2010 Warrants	'	'
Class of Warrant or Right [Line Items]	'	'
Expected term (in years)	'1 year 7 months 10 days	'1 year 10 months 10 days
Estimated volatility	45.00%	41.00%
Risk-free interest rate	0.44%	0.38%
Expected dividend yield	0.00%	0.00%

StockBased_Compensation_Additi

Stock-Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended			0 Months Ended			0 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Jun. 12, 2013	Jun. 06, 2012	Mar. 31, 2014	Jun. 06, 2012	Mar. 31, 2014
			Restricted Stock Units (RSUs)	2008 Equity Incentive Plan	2008 Equity Incentive Plan	2008 Equity Incentive Plan	Employee Stock Purchase Plan	Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'	'	'
Increase in shares of common stock authorized for issuance	'	'	'	6,000,000	3,000,000	'	500,000	'
Maximum number of shares of common stock authorized for issuance	'	'	'	19,540,940	'	'	1,320,500	'
Number of shares available for future issuance	18,100,000	'	'	'	'	5,800,000	'	500,000
Outstanding options and other stock based awards	12,300,000	'	'	'	'	'	'	'
Restricted stock units vesting Description	'	'	'The restricted stock units generally vest in three annual installments from the date of grant and are generally issuable at the end of the three-year vesting term.	'	'	'	'	'
Performance-based stock options awards	$0	$0	'	'	'	'	'	'
Performance-based stock options, outstanding	50,000	'	'	'	'	'	'	'

Activity_Under_Equity_Incentiv

Activity Under Equity Incentive Plans Related to Stock Options (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014
Activity under the Company's equity incentive plans related to stock options	'
Number of Options Outstanding, Beginning Balance	10,405
Granted, Number of Options Outstanding	2,347
Forfeited, Number of Options Outstanding	-36
Expired, Number of Options Outstanding	-30
Exercised, Number of Options Outstanding	-478
Number of Options Outstanding, Ending Balance	12,208
Weighted Average Exercise Price per Share	'
Weighted Average Exercise Price per Share, Beginning Balance	$3.46
Granted, Weighted Average Exercise Price per Share	$6.20
Forfeited, Weighted Average Exercise Price per Share	$4.49
Expired, Weighted Average Exercise Price per Share	$9.78
Exercised, Weighted Average Exercise Price per Share	$2.65
Weighted Average Exercise Price per Share, Ending Balance	$4

StockBased_Compensation_Recogn

Stock-Based Compensation Recognized on Condensed Consolidated Statements of Operations (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	$945	$713
Research and Development Expense	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	183	87
Selling, General and Administrative Expenses	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	$762	$626

Development_and_License_Agreem1

Development and License Agreements - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Licenses Agreements [Line Items]	'	'
Royalty payments on products	$0.70	$0.80
Payments made relating to the manufacturing of the products	4.6	3.9
Prior written notice for termination of agreement	'24 months	'
Revenue from sale of components	2.7	'
Fresenius	'	'
Licenses Agreements [Line Items]	'	'
Prior written notice for termination of agreement	'30 months	'
Royalty	'	'
Licenses Agreements [Line Items]	'	'
Royalties owed	0.6	0.7
Royalty | Platelet system	'	'
Licenses Agreements [Line Items]	'	'
Royalty rate applied towards sale of products	10.00%	'
Royalty | Plasma system	'	'
Licenses Agreements [Line Items]	'	'
Royalty rate applied towards sale of products	3.00%	'
Manufacturing Costs	'	'
Licenses Agreements [Line Items]	'	'
Royalties owed	$3.40	$4.30

Segment_Customer_and_Geographi2

Segment, Customer and Geographic Information - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2014
	Segment
Segment Reporting Information [Line Items]	'
Number of operating segments	1

Significant_Customers_that_Acc

Significant Customers that Accounted for More than Ten Percentage of Total Product Revenue (Detail)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Delrus Inc.	'	'
Revenue, Major Customer [Line Items]	'	'
Percentage of revenue derived from significant customer from Company's total product revenue	'	19.00%
Movaco, S.A.	'	'
Revenue, Major Customer [Line Items]	'	'
Percentage of revenue derived from significant customer from Company's total product revenue	19.00%	19.00%
Etablissement Francais du Sang	'	'
Revenue, Major Customer [Line Items]	'	'
Percentage of revenue derived from significant customer from Company's total product revenue	23.00%	16.00%