Dyax (DYAX) Inactive 10-K27 Feb 152014 FY Annual reportFinancial data

Company Profile

Document_And_Entity_Informatio

Document And Entity Information (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Feb. 23, 2015	Jun. 30, 2014
Document Information [Line Items]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Entity Registrant Name	DYAX CORP
Entity Central Index Key	907562
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$807
Trading Symbol	DYAX
Entity Common Stock, Shares Outstanding		136,789,839

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$19,392	$68,085
Short-term investments	165,260	43,296
Accounts receivable, net	12,221	6,506
Inventory	4,504	2,827
Other current assets	7,053	1,618
Total current assets	208,430	122,332
Fixed assets, net	4,631	4,960
Restricted cash	1,100	1,100
Other assets	2,972	5,815
Total assets	217,133	134,207
Current liabilities:
Accounts payable and accrued expenses	17,373	12,542
Current portion of deferred revenue	3,373	2,686
Current portion of long-term obligations	0	468
Other current liabilities	1,159	1,812
Total current liabilities	21,905	17,508
Deferred revenue	4,201	5,335
Note payable	82,165	81,516
Long-term obligations	0	463
Deferred rent and other long-term liabilities	3,059	3,063
Total liabilities	111,330	107,885
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value; 1,000,000 shares authorized; 0 and 41,418 shares issued and outstanding at December 31, 2014 and 2013, respectively	0	0
Common stock, $0.01 par value; 200,000,000 shares authorized; 136,662,175 and 121,704,480 shares issued and outstanding at December 31, 2014 and 2013, respectively	1,367	1,217
Additional paid-in capital	650,249	559,065
Accumulated deficit	-545,841	-533,963
Accumulated other comprehensive income	28	3
Total stockholders' equity	105,803	26,322
Total liabilities and stockholders' equity	$217,133	$134,207

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	41,418
Preferred stock, shares outstanding	0	41,418
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	136,662,175	121,704,480
Common stock, shares outstanding	136,662,175	121,704,480

Consolidated_Statements_of_Ope

Consolidated Statements of Operations and Comprehensive Loss (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues:
Product sales, net	$68,272	$40,526	$39,783
Development and license fees	9,669	13,400	14,867
Royalty revenue	3,782	0	0
Total revenues	81,723	53,926	54,650
Costs and expenses:
Cost of product sales	4,706	2,688	2,152
Cost of royalty revenue	1,891	0	0
Research and development	35,942	29,695	30,028
Selling, general and administrative	40,419	38,742	39,915
Restructuring	0	0	1,440
Total costs and expenses	82,958	71,125	73,535
Loss from operations	-1,235	-17,199	-18,885
Other income (expense):
Interest and other income	274	214	111
Interest expense	-10,917	-10,792	-10,491
Total other expense, net	-10,643	-10,578	-10,380
Net loss	-11,878	-27,777	-29,265
Other comprehensive loss:
Unrealized gain (loss) on investments	25	-3	-1
Comprehensive loss	($11,853)	($27,780)	($29,266)
Basic and diluted net loss per share:
Net loss per share attributable to common stockholders	($0.09)	($0.26)	($0.30)
Shares used in computing basic and diluted net loss per share	133,367,963	108,539,613	98,991,056

Consolidated_Statements_of_Cha

Consolidated Statements of Changes in Stockholders' Equity (Deficit) (USD $)	Total	Common Stock	Preferred Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income
In Thousands, except Share data	Total	Common Stock	Preferred Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income
Balance at Dec. 31, 2011	($27,399)	$988	$0	$448,527	($476,921)	$7
Balance (in shares) at Dec. 31, 2011		98,798,065	0
Common stock issued under stock plans	1,442	7	0	1,435	0	0
Common stock issued under stock plans (in shares)		684,564	0
Share-based compensation expense	3,663	0	0	3,663	0	0
Unrealized gain (loss) on investments	-1	0	0	0	0	-1
Net loss	-29,265	0	0	0	-29,265	0
Balance at Dec. 31, 2012	-51,560	995	0	453,625	-506,186	6
Balance (in shares) at Dec. 31, 2012		99,482,629	0
Common stock issued under stock plans	5,360	22	0	5,338	0	0
Common stock issued under stock plans (in shares)		2,199,688	0
Sale of common and preferred stock	93,775	195	0	93,580	0	0
Sale of common and preferred stock (in shares)		19,517,060	41,418
Exercise of warrants	0	2	0	-2	0	0
Exercise of warrants (in shares)		233,438	0
Other issuance of common stock	1,076	3	0	1,073	0	0
Other issuance of common stock (in shares)		271,665	0
Share-based compensation expense	5,451	0	0	5,451	0	0
Unrealized gain (loss) on investments	-3	0	0	0	0	-3
Net loss	-27,777	0	0	0	-27,777	0
Balance at Dec. 31, 2013	26,322	1,217	0	559,065	-533,963	3
Balance (in shares) at Dec. 31, 2013		121,704,480	41,418
Common stock issued under stock plans	4,273	16	0	4,257	0	0
Common stock issued under stock plans (in shares)		1,615,895	0
Sale of common and preferred stock	79,708	92	0	79,616	0	0
Sale of common and preferred stock (in shares)		9,200,000	0
Preferred stock conversion	0	42	0	-42	0	0
Preferred stock conversion (in shares)		4,141,800	-41,418
Share-based compensation expense	7,353		0	7,353	0	0
Unrealized gain (loss) on investments	25		0	0	0	25
Net loss	-11,878		0	0	-11,878	0
Balance at Dec. 31, 2014	$105,803	$1,367	$0	$650,249	($545,841)	$28
Balance (in shares) at Dec. 31, 2014		136,662,175	0

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net loss	($11,878)	($27,777)	($29,265)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of investment premium/discount	639	30	64
Depreciation and amortization of fixed assets and intangible assets	868	861	1,060
Non-cash interest expense	649	3,455	2,784
Gain on disposal of fixed assets	0	0	-110
Share-based compensation expense	7,283	5,441	3,640
Provision for doubtful accounts	0	0	-80
Non-cash stock issuance	0	1,076	0
Non-cash other income	0	0	-68
Changes in operating assets and liabilities
Accounts receivable	-4,954	1,001	-1,335
Other current assets	-5,434	541	2,809
Inventory	1,203	1,637	-2,916
Accounts payable and accrued expenses	4,193	1,900	-2,113
Deferred revenue	-1,207	-3,830	-4,051
Long-term deferred rent	-230	-123	685
Other	257	-28	414
Net cash used in operating activities	-8,611	-15,816	-28,482
Cash flows from investing activities:
Purchase of investments	-124,579	-43,301	-6,057
Proceeds from maturity of investments	2,000	9,000	23,000
Purchase of fixed assets	-553	-507	-4,066
Proceeds from sale of fixed assets	0	0	200
Restricted cash	0	0	1,266
Net cash (used in) provided by investing activities	-123,132	-34,808	14,343
Cash flows from financing activities:
Gross proceeds from stock offerings	85,100	99,000	0
Fees associated with stock offerings	-5,392	-5,225	0
Proceeds from issuance of note payable	0	0	1,382
Repayment of long-term obligations	-931	-445	-135
Proceeds from the issuance of common stock under employee stock purchase plan and exercise of stock options	4,273	5,361	1,442
Net cash provided by financing activities	83,050	98,691	2,689
Net (decrease) increase in cash and cash equivalents	-48,693	48,067	-11,450
Cash and cash equivalents at beginning of the period	68,085	20,018	31,468
Cash and cash equivalents at end of the period	19,392	68,085	20,018
Supplemental disclosure of cash flow information:
Issuance of common shares on exercise of warrants - see Note 8	0	2,093	0
Interest paid	10,889	5,525	9,364
Preferred stock conversion to common stock	$9,526	$0	$0

Nature_of_Business

Nature of Business	12 Months Ended
	Dec. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Business	1. Nature of Business

	Dyax Corp. (Dyax or the Company) is a biopharmaceutical company focused on:

		⋅	Hereditary Angioedema and Other Plasma-Kallikrein-Mediated Disorders
	The Company develops and commercializes treatments for HAE and is working to identify additional disorders that are mediated by plasma kallikrein.

	The Company discovered and developed KALBITOR^® (ecallantide), a plasma kallikrein inhibitor, and is selling this product in the United States for the treatment of acute attacks of HAE. Additionally, the Company discovered and is developing DX-2930, a fully human monoclonal antibody inhibitor of plasma kallikrein, which is believed to be a candidate to treat HAE prophylactically.

	The Company has also developed a biomarker assay that detects the activation of plasma kallikrein in patient blood. It intends to use this assay to expedite the development of DX-2930.

		⋅	Licensing and Funded Research Portfolio (LFRP)
	The Company has a portfolio of product candidates being developed by licensees using its phage display technology. This portfolio currently includes one approved product, CYRAMZA (ramucirumab) marketed by Lilly, and multiple product candidates in various stages of clinical development, including three in Phase 3 trials, for which the Company is eligible to receive future royalties and/or milestone payments.

Accounting_Policies

Accounting Policies

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Accounting Policies

2. Accounting Policies

Basis of Consolidation

The accompanying consolidated financial statements for the years ended December 31, 2013 and 2012 include the accounts of the Company and the Company's European subsidiaries Dyax S.A., Dyax BV and Dyax BV Holding. In 2014, Dyax S.A. and Dyax BV were dissolved. For the year ended December 31, 2014 the accompanying financial statements include the accounts of the Company and Dyax BV Holding. All inter-company accounts and transactions have been eliminated.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make certain estimates and assumptions that affect the amounts of assets and liabilities reported and disclosure of contingent assets and liabilities at the dates of the financial statements and the reported amounts of revenue and expenses during the reporting periods. The significant estimates and assumptions in these financial statements include revenue recognition, product sales allowances, effective interest rate calculation, useful lives with respect to long lived assets, valuation of stock options, accrued expenses and tax valuation reserves. Actual results could differ from those estimates.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents, short-term investments and trade accounts receivable. At December 31, 2014 and 2013, approximately 98% and 89%, respectively, of the Company's cash, cash equivalents and short-term investments were invested in money market funds backed by U.S. Treasury obligations, U.S. Treasury notes and bills, and obligations of United States government agencies held by one financial institution. The Company maintains balances in various operating accounts in excess of federally insured limits.

The Company provides most of its services and licenses its technology to pharmaceutical and biomedical companies worldwide, and makes all product sales to its distributors. Concentrations of credit risk with respect to trade receivable balances associated the Company’s development and license fee revenue are usually limited on an ongoing basis, due to the diverse number of licensees and collaborators comprising the Company's customer base. Trade receivable balances associated with the Company’s product sales are comprised of a few customers due to the Company’s limited distribution network. The Company completes ongoing credit evaluations of their customers. As of December 31, 2014, three companies accounted for 27% (Lilly), 21% (US Bioservices) and 20% (Walgreens) of the accounts receivable balance. The balance due from Lilly includes $1.7 million in unbilled accounts receivable. Two companies accounted for approximately 35% (US Bioservices) and 26% (Walgreens) of the Company's accounts receivable balance as of December 31, 2013.

The Company’s two largest distributors of KABITOR are Walgreens and US Bioservices. During the years ended December 31, 2014, 2013 and 2012, sales to Walgreens were 34%, 38% and 40% of total revenue, respectively; and, sales to US Bioservices were 28%, 26% and 30% of total revenue, respectively.

Revenues from customers outside the United States, principally related to development and license agreements, were approximately 3%, 13% and 13% of total revenues for the years ended December 31, 2014, 2013 and 2012, respectively.

Cash and Cash Equivalents

All highly liquid investments purchased with an original maturity of ninety days or less are considered to be cash equivalents. Cash and cash equivalents consist principally of cash, money market and U.S. Treasury funds.

Investments

Short-term investments primarily consist of investments with original maturities greater than ninety days and remaining maturities less than one year at period end. The Company has also classified its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations. The Company considers its investment portfolio of investments available-for-sale. Accordingly, these investments are recorded at fair value, which is based on quoted market prices. As of December 31, 2014, the Company's investments consisted of U.S. Treasury notes and bills with an amortized cost of $165.2 million, an estimated fair value of $165.3 million, and had an unrealized gain of $28,000. As of December 31, 2013, the Company's investments consisted of United States Treasury notes and bills with an estimated fair value and amortized cost of $43.3 million, and had an unrealized gain of $3,000, which is recorded in other comprehensive income on the accompanying consolidated balance sheet.

Inventories

Inventories are stated at the lower of cost or market with cost determined under the first-in, first-out, or FIFO, basis. The Company evaluates inventory levels and would write-down inventory that is expected to expire prior to being sold, inventory that has a cost basis in excess of its expected net realizable value, inventory in excess of expected sales requirements, or inventory that fails to meet commercial sale specifications, through a charge to cost of product sales. Included in the cost of inventory are capitalized employee stock-based compensation costs for those employees dedicated to manufacturing efforts. Inventory on-hand that will be sold beyond the Company's normal operating cycle is classified as non-current and grouped with other assets on the Company's consolidated balance sheet.

Inventories consist principally of raw materials and work-in-process. In certain circumstances, the Company will make advance payments to vendors for future inventory deliveries. These advance payments are recorded as other current assets on the consolidated balance sheet.

Fixed Assets

Property and equipment are recorded at cost and depreciated over the estimated useful lives of the related assets using the straight-line method. Laboratory and production equipment, furniture and office equipment are depreciated over a three to seven year period. Leasehold improvements are stated at cost and are amortized over the lesser of the non-cancelable term of the related lease or their estimated useful lives. Leased equipment is amortized over the lesser of the life of the lease or their estimated useful lives. Maintenance and repairs are charged to expense as incurred. When assets are retired or otherwise disposed of, the cost of these assets and related accumulated depreciation and amortization are eliminated from the balance sheet and any resulting gains or losses are included in operations in the period of disposal.

The Company records all proceeds received from the lessor for tenant improvements under the terms of its operating lease as deferred rent. The amounts are amortized on a straight-line basis over the term of the lease as an offset to rent expense.

Impairment of Long-Lived Assets

The Company reviews its long-lived assets for impairment whenever events or changes in business circumstances indicate that the carrying amount of assets may not be fully recoverable or that the useful lives of these assets are no longer appropriate. Each impairment test is based on a comparison of the undiscounted cash flow to the recorded value of the asset or asset group. If impairment is indicated, the asset is written down to its estimated fair value, which is computed based on a discounted cash flow basis.

Revenue Recognition

The Company’s principal sources of revenue are product sales of KALBITOR and license fees, funding for research and development, and milestones and royalties derived from collaboration and license agreements. In all instances, revenue is recognized only when the price is fixed or determinable, persuasive evidence of an arrangement exists, delivery has occurred or services have been rendered, collectability of the resulting receivable is reasonably assured and the Company has no further performance obligations.

Product Sales and Allowances

Product Sales. Product sales are generated from the sale of KALBITOR to the Company’s customers, primarily wholesale and specialty distributors, and are recorded upon delivery when title and risk of loss have passed to the customer. Product sales are recorded net of applicable reserves for distributors, prompt pay and other discounts, government rebates, patient financial assistance programs, product returns and other applicable allowances.

Under certain arrangements the Company has provided their distributors with extended payment terms. In these circumstances, revenue is not recognized until collectability is reasonably assured.

Product Sales Allowances. The Company establishes reserves for trade distributor, prompt pay and volume discounts, government rebates, patient financial assistance programs, product returns and other applicable allowances. Reserves established for these discounts and allowances are classified as a reduction of accounts receivable (if the amount is payable to the customer) or a liability (if the amount is payable to a party other than the customer).

Allowances against receivable balances primarily relate to prompt payment discounts and are recorded at the time of sale, resulting in a reduction in product sales revenue. Accruals related to government rebates, patient financial assistance programs, product returns and other applicable allowances are recognized at the time of sale, resulting in a reduction in product sales revenue and an increase in accrued expenses.

The Company maintains service contracts with its distributors. These contracts include services such as inventory maintenance and patient support services, which have included call center and on-demand nursing services. Accounting standards related to consideration given by a vendor to a customer, including a reseller of a vendor’s product, specify that each consideration given by a vendor to a customer is presumed to be a reduction of the selling price. Consideration should be characterized as a cost if the company receives, or will receive, an identifiable benefit in exchange for the consideration, and fair value of the benefit can be reasonably estimated. The Company has established that patient support services are at fair value and represent a separate and identifiable benefit because these services could be provided by separate third-party vendors. Accordingly, these costs are classified as selling, general and administrative expense.

Fees paid to distributors for inventory maintenance are calculated as a percentage of KALBITOR sales price and accordingly, are classified as a reduction in product sales revenue.

Prompt Payment and Other Discounts. The Company offers a prompt payment discount to its United States distributors. Since the Company expects that these distributors will take advantage of this discount, the Company accrues 100% of the prompt payment discount that is based on the gross amount of each invoice, at the time of sale. This accrual is adjusted quarterly to reflect actual earned discounts. The Company has also offered volume discounts to certain distributors which are accrued quarterly based on sales during the period.

Government Rebates and Chargebacks. The Company estimates reductions to product sales for Medicaid and Veterans' Administration (VA) programs and the Medicare Part D Coverage Gap Program, as well as for certain other qualifying federal and state government programs. The Company estimates the amount of these reductions based on available KALBITOR patient data, actual sales data and rebate claims. These allowances are adjusted each period based on actual experience.

Medicaid rebate reserves relate to the Company’s estimated obligations to state jurisdictions under the established reimbursement arrangements of each applicable state. Rebate accruals are recorded during the same period in which the related product sales are recognized. Actual rebate amounts are determined at the time of claim by the state, and the Company will generally make cash payments for such amounts after receiving billings from the state.

VA rebates or chargeback reserves represent the Company’s estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at a price lower than the list price charged to the Company’s distributor. The distributor will charge the Company for the difference between what the distributor pays for the product and the ultimate selling price to the qualified healthcare provider. Rebate accruals are established during the same period in which the related product sales are recognized. Actual chargeback amounts for Public Health Service are determined at the time of resale to the qualified healthcare provider from the distributor, and the Company will generally issue credits for such amounts after receiving notification from the distributor.

Although allowances and accruals are recorded at the time of product sale, certain rebates are typically paid out, on average, up to six months or longer after the sale. Reserve estimates are evaluated quarterly and if necessary, adjusted to reflect actual results. Any such adjustments will be reflected in the Company’s operating results in the period of the adjustment.

Product Returns. Allowances for product returns are recorded during the period in which the related product sales are recognized, resulting in a reduction to product revenue. The Company does not provide its distributors with a general right of product return. The Company permits returns if the product is damaged or defective when received by customers or if the product shelf life has expired. The Company estimates product returns based upon actual returns history and data provided by a distributor.

Patient Financial Assistance. The Company offers a financial assistance program for commercially insured KALBITOR patients in order to defray patients’ out-of-pocket expenses, including co-payments, to aid patients’ access to KALBITOR. The Company estimates its liability for this program based on actual but unpaid reimbursements, as well as, an estimated reserve for product sold to and held by distributors as of period end, based on the Company’s historical redemption rates.

An analysis of the amount of, and change in, reserves related to sales allowances is summarized as follows:

Prompt pay

Government

and other

Patient financial

rebates and

(In thousands)

discounts

assistance

chargebacks

Returns

Total

Balance, as of December 31, 2012

388

165

565

551

1,669

Current provisions relating to sales in current year

2,565

498

2,806

145

6,014

Adjustments relating to prior years

-38

-79

-141

-235

Payments relating to sales in current year

-2,165

-378

-1,380

—

-3,923

Payments/returns relating to sales in prior years

-327

-157

-278

-232

-994

Balance, as of December 31, 2013

484

1,634

323

2,531

Current provisions relating to sales in current year

3,593

443

3,270

267

7,573

Adjustments relating to prior years

-209

-148

Payments relating to sales in current year

-3,154

-385

-1,800

—

-5,339

Payments/returns relating to sales in prior years

-383

-16

-908

-42

-1,349

Balance, as of December 31, 2014

546

143

1,987

592

3,268

Development and License Fee Revenues

Collaboration Agreements. The Company enters into collaboration agreements with other companies for the research and development of therapeutic and diagnostic products. The terms of the agreements may include non-refundable signing and licensing fees, funding for research and development, payments related to manufacturing services, milestone payments and royalties on any product sales derived from collaborations. These multiple element arrangements are analyzed to determine how the deliverables, which often include license and performance obligations such as research, steering committee and manufacturing services, are separated into units of accounting.

For agreements entered into prior to 2011, the Company evaluated license arrangements with multiple elements in accordance with Accounting Standards Codification (ASC), 605-25 Revenue Recognition – Multiple-Element Arrangements. Since 2011, the Company has applied the guidance of ASU 2009-13 to evaluate license arrangements with multiple elements. This guidance amended the accounting standards for certain multiple element arrangements to:

Provide updated guidance on whether multiple elements exist, how the elements in an arrangement should be separated and how the arrangement considerations should be allocated to the separate elements;

Require an entity to allocate arrangement consideration to each element based on a selling price hierarchy, also called the relative selling price method, where the selling price for an element is based on vendor-specific objective evidence (VSOE), if available; third-party evidence (TPE), if available and VSOE is not available; or the best estimate of selling price (BESP), if neither VSOE or TPE is available; and

Eliminate the use of the residual method and require an entity to allocate arrangement consideration using the selling price hierarchy.

The Company evaluates all deliverables within an arrangement to determine whether or not they provide value to the licensee on a stand-alone basis. Based on this evaluation, the deliverables are separated into units of accounting. If VSOE or vendor objective evidence (VOE) is not available to determine the fair value of a deliverable, the Company determines the best estimate of selling price associated with the deliverable. The arrangement consideration, including upfront license fees and funding for research and development, is allocated to the separate units based on relative fair value.

VSOE is based on the price charged when an element is sold separately and represents the actual price charged for that deliverable. When VSOE cannot be established, the Company attempts to establish the selling price of the elements of a license arrangement based on VOE. VOE is determined based on third party evidence for similar deliverables when sold separately. In circumstances when the Company charges a licensee for pass-through costs paid to external vendors for development services, these costs represent VOE.

When the Company is unable to establish the selling price of an element using VSOE or VOE, management determines BESP for that element. The objective of BESP is to determine the price at which the Company would transact a sale if the element within the license agreement was sold on a stand-alone basis. The Company’s process for establishing BESP involves management’s judgment and considers multiple factors including discounted cash flows, estimated direct expenses and other costs and available data.

Based on the value allocated to each unit of accounting within an arrangement, upfront fees and other guaranteed payments are allocated to each unit based on relative value. The appropriate revenue recognition method is applied to each unit and revenue is accordingly recognized as each unit is delivered.

For agreements entered into prior to 2011, revenue related to upfront license fees was spread over the full period of performance under the agreement, unless the license was determined to provide value to the licensee on a stand-alone basis and the fair value of the undelivered performance obligations, typically including research or steering committee services was determinable.

Steering committee services that were not inconsequential or perfunctory and were determined to be performance obligations were combined with other research services or performance obligations required under an arrangement, if any, to determine the level of effort required in an arrangement and the period over which the Company expected to complete its aggregate performance obligations.

Whenever the Company determined that an arrangement should be accounted for as a single unit of accounting, it determined the period over which the performance obligations would be completed. Revenue is recognized using either an efforts-based or time-based proportional performance (i.e. straight-line) method. The Company recognizes revenue using an efforts-based proportional performance method when the level of effort required to complete its performance obligations under an arrangement can be reasonably estimated and such performance obligations are provided on a best-efforts basis. Direct labor hours or full-time equivalents are typically used as the measurement of performance.

If the Company cannot reasonably estimate the level of effort to complete its performance obligations under an arrangement, then revenue under the arrangement is recognized on a straight-line basis over the period the Company is expected to complete its performance obligations.

Many of the Company's collaboration agreements entitle it to additional payments upon the achievement of performance-based milestones. Milestones that are tied to development or regulatory approval are not considered probable of being achieved until such approval is received. All milestones which are determined to be substantive milestones are recognized as revenue in the period in which they are met in accordance with Accounting Standards Update (ASU) No. 2010-17, Revenue Recognition – Milestone Method. Milestones tied to counter-party performance are not included in the Company’s revenue model until performance conditions are met. Milestones determined to be non-substantive are allocated to each unit of accounting within an arrangement when met. The allocation of the milestone to each unit is based on relative value and revenue related to each unit is recognized accordingly.

Costs of revenues related to licensees’ product development, including license fees and development and regulatory milestones are classified as research and development in the consolidated statements of operations and comprehensive loss.

Phage Display Library Licenses. Standard terms of the proprietary phage display library agreements generally include non-refundable signing fees, license maintenance fees, development milestone payments, product license payments and royalties on product sales. Signing fees and maintenance fees are generally recognized on a straight line basis over the term of the agreement as deliverables within these arrangements are determined to not provide the licensee with value on a stand-alone basis and therefore are accounted for as a single unit of accounting. As milestones are achieved under a phage display library license, a portion of the milestone payment, equal to the percentage of the performance period completed when the milestone is achieved, multiplied by the amount of the milestone payment, will be recognized. The remaining portion of the milestone will be recognized over the remaining performance period on a straight-line basis. If the Company has no future obligations under the license, milestone payments under these license arrangements are recognized as revenue when the milestone is achieved. Product license payments, which are optional to the licensee, are substantive and therefore are excluded from the initial allocation of the arrangement consideration. These payments are recognized as revenue when the license is issued upon exercise of the licensee’s option, if the Company has no future obligations under the agreement. If there are future obligations under the agreement, product license payments are recognized as revenue only to the extent of the fair value of the license. Amounts paid in excess of fair value are recognized in a manner similar to milestone payments. Payments received that have not met the appropriate criteria for revenue recognition are recorded as deferred revenue.

Phage Display Patent Licenses. The Company previously licensed its phage display patents on a non-exclusive basis to third parties for use in connection with the research and development of therapeutic, diagnostic, and other products. The core patents in this portfolio expired in November 2012. Even after patent expiration, the Company generally remains eligible under these patent licenses to receive milestones and/or royalties for products discovered prior to patent expiration, although certain existing patent licenses will no longer have a royalty obligation. The Company does not expect the expiration of these patents to have a material impact on the LFRP.

Standard terms of the patent rights agreements include non-refundable signing fees, non-refundable license maintenance fees, development milestone payments and/or royalties on product sales. Signing fees and maintenance fees are generally recognized on a straight line basis over the term of the agreement or through the date of patent expiry, if shorter, except that in the case of perpetual patent licenses for which fees were recognized immediately if it was determined that the Company had no future obligations under the agreement and the payments were made upfront. If the Company has no remaining performance obligations under the patent license agreement, milestones are recognized as revenue in the period in which the milestone is achieved.

LFRP Milestones

Non-substantive Milestones. Under the LFRP licenses, the Company is eligible to receive clinical development, regulatory filing and marketing approval milestones, which vary from licensee to licensee. Achievement of these milestones is contingent upon each licensee’s efforts and involves risks and uncertainty related to drug development, regulatory approval and intellectual property that could lead to milestones never being met.

Based on information available to the Company regarding pre-clinical and clinical candidates in the LFRP developed using its technology and through intellectual property rights granted, it is estimated that the Company could receive up to $81 million in development milestones, $67 million in regulatory filing milestones and $96 million in marketing approval milestones. As achievement of these milestones is outside the control of the Company and is contingent upon the licensees’ efforts, they have been determined to be non-substantive milestones.

The Company recognized revenue of approximately $4.5 million, $3.1 million and $3.3 million related to milestones under the LFRP for the years ended December 31, 2014, 2013 and 2012, respectively.

Substantive Milestones. Under certain collaboration agreements, the Company performs funded research for various collaborators using its phage display technology and libraries. These arrangements typically include technical milestones that are based on agreed upon objectives to be met under the research campaign, which are considered to be commensurate with the Company’s performance and therefore have been determined to be substantive milestones.

During the year ended December 31, 2012, the Company recognized revenue of approximately $327,000 for technical milestones. There was no amount recognized during the years ended December 31, 2014 and 2013. The Company is not eligible to receive any future technical milestones at this time.

Non-LFRP Milestones

In certain countries outside of the U.S., the Company has entered into licensing agreements for the development and commercialization of KALBITOR for the treatment of HAE and other angioedema indications. Under these agreements, the Company is eligible to receive certain development and sales milestones. See Note 3, Significant Transactions.

Royalty Revenue

Royalty revenue is recognized when it becomes determinable and collectability is reasonably assured. For royalties recognized related to CYRAMZA, the first therapeutic product in the LFRP, which is commercialized by Lilly, the Company is contractually entitled to receive a royalty report from Lilly subsequent to each quarter end. Upon initial commercialization of CYRAMZA in the second quarter of 2014, the Company recognized royalty revenue one quarter in arrears from the related sales as it has not been able to determine royalty revenue until receipt of this report. Beginning with the fourth quarter of 2014, the Company has recognized royalty revenue using an estimate of the royalties earned for the quarter based on Lilly’s reported sales of CYRAMZA.

Cost of Product Sales and Royalties

Cost of product sales includes costs to procure, manufacture and distribute KALBITOR and manufacturing royalties. Costs associated with the manufacture of KALBITOR prior to regulatory approval in the United States were expensed when incurred as a research and development cost and accordingly, KALBITOR units sold during the years ended December 31, 2013 and 2012 do not include the full cost of drug manufacturing. For the year ended December 31, 2014, KALBITOR units sold included the full cost of drug manufacturing.

Cost of royalties is derived from pass-through fees under the Company’s cross license agreement related to royalties from product sales by its LFRP licensees.

Research and Development

Research and development costs include all direct costs, including salaries and benefits for research and development personnel, outside consultants, costs of clinical trials, sponsored research, clinical trials insurance, other outside costs, depreciation and facility costs related to the development of drug candidates, as well as certain pass-through costs under the Company’s cross license agreements related to product development by its LFRP licensees, including license fees and development and regulatory milestones.

Income Taxes

The Company utilizes the asset and liability method of accounting for income taxes in accordance with ASC 740. Under this method, deferred tax assets and liabilities are recognized for the expected future tax consequences of temporary differences between the carrying amounts and the tax basis of assets and liabilities using the enacted statutory tax rates. At December 31, 2014 and 2013, there were no unrecognized tax benefits.

The Company accounts for uncertain tax positions using a "more-likely-than-not" threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors that include, but are not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The provision for income taxes includes the effects of any resulting tax reserves or unrecognized tax benefits that are considered appropriate as well as the related net interest and penalties, if any. The Company evaluates uncertain tax positions on a quarterly basis and adjusts the level of the liability to reflect any subsequent changes in the relevant facts surrounding the uncertain positions.

Translation of Foreign Currencies

Assets and liabilities of the Company's foreign subsidiaries are translated at period end exchange rates. Amounts included in the statements of operations are translated at the average exchange rate for the period. As the Company’s foreign subsidiaries are U.S. dollar functional currency denominated, local currency is remeasured in U.S. dollars and are recorded to other income (expense) in the consolidated statement of operations and comprehensive loss. The Company recorded other expense of $33,000 for the year ended December 31, 2014 and other income of $14,000 and $15,000, for the years ended December 31, 2013 and 2012, respectively.

Share-Based Compensation

The Company’s share-based compensation program consists of share-based awards granted to employees in the form of stock options and restricted stock units, as well as its 1998 Employee Stock Purchase Plan, as amended (the Purchase Plan). The Company’s share-based compensation expense is recorded in accordance with ASC 718.

Income or Loss Per Share

The Company follows the two-class method when computing net loss per share, as it had issued shares that met the definition of participating securities. The two-class method determines net loss per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to receive dividends, as if all income for the period had been distributed.

The Company presents two earnings or loss per share (EPS) amounts, basic and diluted in accordance with ASC 260. Basic earnings or loss per share is computed using the weighted average number of shares of common stock outstanding. Diluted net loss per share does not differ from basic net loss per share since potential common shares from the exercise of stock options, warrants or rights under the Purchase Plan are anti-dilutive for the years ended December 31, 2014, 2013 and 2012, and therefore, are excluded from the calculation of diluted net loss per share.

The weighted average of stock options, restricted stock units and warrants outstanding totaled 12.2 million, 12.2 million and 12.3 million at December 31, 2014, 2013, and 2012, respectively.

Comprehensive Income (Loss)

The Company accounts for comprehensive income (loss) under ASC 220, Comprehensive Income, which established standards for reporting and displaying comprehensive income (loss) and its components in a full set of general purpose financial statements. The statement required that all components of comprehensive income (loss) be reported in a financial statement that is displayed with the same prominence as other financial statements. The Company is presenting comprehensive income (loss) as part of the consolidated statements of operations and comprehensive loss.

Business Segments

The Company discloses business segments under ASC 280, Segment Reporting. The statement established standards for reporting information about operating segments and disclosures about products and services, geographic areas and major customers. The Company operates in one business segment as a biopharmaceutical company within predominantly one geographic area. Long-lived assets consist entirely of property and equipment and are located in the United States for all periods presented.

Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies, which are adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that recently issued standards that are not yet effective will not have a material impact on its financial position or results of operations upon adoption.

In May 2014, the FASB issued an amendment which will replace most of the existing revenue recognition guidance within U.S. GAAP. The core principle of this guidance is that an entity should recognize revenue for the transfer of goods or services to customers in an amount that it expects to be entitled to receive for those goods or services. In doing so, companies will be required to make certain judgments and estimates, including identifying contract performance obligations, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price among separate performance obligations. Additionally, the amendment requires disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, significant judgments reached in the application of the guidance and assets recognized from the costs to obtain or fulfill a contract. Effective for the Company beginning on January 1, 2017, the amendment allows for two methods of adoption, a full retrospective method or a modified retrospective approach with the cumulative effect recognized at the date of initial application. Early adoption is not permitted. The Company is in the process of determining the method of adoption and the impact of this amendment on its consolidated financial statements.

In August 2014, the FASB issued an amendment that requires management to assess an entity’s ability to continue as a going concern by incorporating and expanding upon certain principles that are currently in U.S. auditing standards. The amendments in this update provide guidance about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern for one year after the date that the financial statements are issued and to provide related footnote disclosures. In doing so, the amendments should reduce diversity in the timing and content of footnote disclosures. The amendments in this update apply to all entities and are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. This amendment is not expected to have a material impact on the Company’s financial statements.

SIGNIFICANT_TRANSACTIONS

SIGNIFICANT TRANSACTIONS	12 Months Ended
SIGNIFICANT TRANSACTIONS	Dec. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Abstract]
SIGNIFICANT TRANSACTIONS	3. SIGNIFICANT TRANSACTIONS

	CVie

	In 2013, the Company entered into an agreement with CVie Therapeutics (CVie), a subsidiary of Lee’s Pharmaceutical Holdings Ltd., to develop and commercialize KALBITOR for the treatment of HAE and other angioedema indications in China, Hong Kong and Macau. Under the terms of this exclusive license agreement, Dyax received a $1.0 million upfront payment and is eligible to receive up to $11 million in future regulatory and sales milestones. In September 2014, the contract was amended to expand CVIE’s territories to include the Republic of Korea, Taiwan and Singapore. The Company is eligible to receive royalties on net product sales in all licensed territories. CVie is solely responsible for all costs associated with development, regulatory activities and the commercialization of KALBITOR in its licensed territories. CVie will purchase drug product from the Company on a cost-plus basis for its commercial supply when and if KALBITOR is approved for commercial sale in the CVie territories.

	The Company analyzed this multiple element arrangement in accordance with ASC 605 and evaluated whether the performance obligations under this agreement, including the product license, steering committee, and manufacturing services should be accounted for as a single unit or multiple units of accounting. Because of the risk associated with obtaining approval for commercial sale in the CVie territories, manufacturing services associated with commercial supply are considered a contingent deliverable and will be accounted for if and when performed. As CVie is required to obtain all drug product for both clinical development and commercial demand from the Company, all other deliverables under this arrangement were determined to provide no stand-alone value to the licensee. Accordingly, it was determined that the license, manufacturing services associated with clinical supply, and steering committee performance obligations under this agreement represent a single unit of accounting.

	At this time, the Company cannot reasonably estimate the level of effort required to fulfill its obligations and, therefore, is recognizing revenue associated with the upfront payment on a straight-line basis through mid-2020, the estimated development period in the CVie territories.

	The Company recognized revenue of $105,000 and $172,000 for the years ended December 31, 2014 and 2013, respectively. As of December 31, 2014 and 2013, the Company has deferred $723,000 and $828,000, respectively of revenue related to this arrangement, which is recorded in deferred revenue on the accompanying consolidated balance sheets.

	Pint/Novellus

	In 2013, the Company entered into an exclusive agreement with Novellus Biopharma AG (Novellus) to develop and commercialize KALBITOR for the treatment of HAE and other angioedema indications in select countries in Latin America, including Argentina, Brazil, Chile, Colombia, Mexico and Venezuela. Under the terms of the exclusive license agreement, the Company received upfront payments totaling $500,000 and is eligible to receive up to $5.2 million in future regulatory and sales milestones and royalties on net product sales. In 2014, this agreement was assigned by Novellus to Pint Pharma (Pint) and amended to include the territories of Algeria, Tunisia, Morocco, and South Africa. Pint is solely responsible for all costs associated with development, regulatory activities, and the commercialization of KALBITOR in their licensed territories. Pint will purchase drug product from the Company on a cost-plus basis for its commercial supply.

	The Company analyzed this multiple element arrangement in accordance with ASC 605 and evaluated whether the performance obligations under this agreement, including the product license, steering committee, and manufacturing services should be accounted for as a single unit or multiple units of accounting. As Pint is required to obtain all drug product for both clinical and commercial demand from the Company, all other deliverables under this arrangement were determined to provide no stand-alone value to the licensee. Accordingly, it was determined that performance obligations under this agreement represent a single unit of accounting.

	The Company will recognize revenue related to this arrangement, including the upfront payments, on a unit output basis, as products under clinical and commercial supply are provided to Pint. As no supply has been provided to Pint to date, no revenue has been recognized under this agreement. The Company has deferred recognition of the upfront payments of $500,000, which is recorded in deferred revenue on the accompanying consolidated balance sheets.

	CMIC

	In 2010, the Company entered into an agreement with CMIC Co., Ltd. (CMIC) to develop and commercialize subcutaneous ecallantide for the treatment of HAE and other angioedema indications in Japan. Under the terms of the agreement, the Company received a $4.0 million upfront payment and was eligible to receive development and sales milestones for ecallantide in HAE and other angioedema indications and royalties on net product sales. CMIC was solely responsible for all costs associated with development, regulatory activities, and commercialization of ecallantide for all angioedema indications in Japan.

	In 2013, CMIC provided the Company written notice of CMIC’s intent to terminate the agreement, effective in June 2014, at which time all of the rights to develop ecallantide in Japan returned to the Company. The Company has no obligations to CMIC in connection with, or following the termination.

	Upon the commencement of the agreement in 2010, the Company analyzed this multiple element arrangement in accordance with ASC 605 and evaluated whether the performance obligations under this agreement, including the product license, development of ecallantide for the treatment of HAE and other angioedema indications in Japan, steering committee, and manufacturing services should be accounted for as a single unit or multiple units of accounting. The Company determined that there were two units of accounting. The first unit of accounting included the product license, the committed future development services and the steering committee involvement. The second unit of accounting relates to the manufacturing services. As the scope and timing of the future development of ecallantide for the treatment of HAE and other indications in the CMIC territory are the joint responsibility of the Company and CMIC, the Company could not reasonably estimate the level of effort required to fulfill its obligations under the first unit of accounting, and, as a result, the Company was recognizing revenue under the first unit of accounting on a straight-line basis over the estimated development period of ecallantide for the treatment of HAE in the CMIC territory.

	Upon receiving notification of CMIC’s irrevocable intent to terminate, the Company determined it had no further obligations under this arrangement, and therefore, the full amount of deferred revenue of $2.0 million was recognized in 2013. The Company recognized revenue of approximately $2.6 million and $755,000 and related to this agreement for the years ended December 31, 2013 and 2012. There is no further revenue to be recognized under this agreement.

	Sigma Tau

	The Company entered into a collaboration agreement and several amendments thereto with Sigma-Tau Rare Diseases S.A. (as successor-in-interest to Defiante Farmaceutica S.A.) (Sigma Tau) to develop and commercialize subcutaneous ecallantide for the treatment of HAE and other therapeutic indications in various territories throughout the world. In 2013, Sigma Tau’s rights to all remaining territories were eliminated under a termination agreement between the Company and Sigma Tau.

	Through the date of termination, Sigma Tau had made aggregate upfront payments of $7.0 million, and payments of $3.8 million for reimbursement associated with development services, and it purchased 787,647 shares of the Company’s common stock for an aggregate purchase price of $3.0 million.

	Through May 2011, revenue under this arrangement was recognized in accordance with Emerging Issues Task Force Issue 00-21, Revenue Arrangements with Multiple Deliverables. In May 2011, in conjunction with the second amendment to this agreement, it was determined that the existing arrangement had been materially modified. As a result, the Company re-evaluated the entire arrangement under ASU No. 2009-13, Revenue Recognition with Multiple Deliverables, as if all modifications since inception were part of the original agreement. All undelivered items under the agreement were identified and allocated to separate units of accounting based on whether the deliverable provided stand-alone value to the licensee. The undelivered items as of the date of the second amendment consisted of (i) committed future development services, (ii) steering committee services and (iii) manufacturing services. Manufacturing services for commercial supply were determined to be a contingent deliverable as the performance of these services were contingent upon Sigma-Tau obtaining regulatory approval in its territories.

	The principal terms of the 2013 termination agreement included provision for (i) the revocation of all licenses granted by the Company to Sigma Tau, (ii) the termination of all other obligations under the license agreement, (iii) the issuance of 271,665 shares of the Company’s common stock to Sigma Tau, and (iv) the right of Sigma Tau to receive $500,000 for every $5.0 million of compensation received by the Company during the next ten years in relation to the potential license or supply of ecallantide exclusively in those territories that had been previously licensed to Sigma Tau. In accordance with ASC 605-50, the $1.1 million determined to be the fair value of the common stock as of the date of issuance was recorded as a reduction to development and license fee revenue on the Company’s statement of operations and $85,000 of deferred revenue attributable to the JSC services was recognized as revenue for the year ended December 31, 2013. For the year ended December 31, 2012, revenue recognized under this arrangement totaled $204,000. No additional revenue is expected to be recognized in future periods.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
Fair Value Measurements	Dec. 31, 2014
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	4. Fair Value Measurements

	The following tables present information about the Company's financial assets that have been measured at fair value as of December 31, 2014 and 2013, and indicate the fair value hierarchy of the valuation inputs utilized to determine such fair value. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. Fair values determined by Level 2 inputs utilize observable inputs other than Level 1 prices, such as quoted prices, for similar assets or liabilities, quoted prices in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability, and includes situations where there is little, if any, market activity for the asset or liability.

				Quoted		Significant
				Prices in		Other		Significant
		December		Active		Observable		Unobservable
		31,		Markets		Inputs		Inputs
	Description	2014		(Level 1)		(Level 2)		(Level 3)
		(in thousands)
	Assets:
	Money Market Funds	$	15,610	$	15,610	$	—	$	—
	US Treasury Bills and Notes		165,260		—		165,260		—
	Total	$	180,870	$	15,610	$	165,260	$	—

				Quoted		Significant
				Prices in		Other		Significant
		December		Active		Observable		Unobservable
		31,		Markets		Inputs		Inputs
	Description	2013		(Level 1)		(Level 2)		(Level 3)
		(in thousands)
	Assets:
	Money Market Funds	$	55,569	$	55,569	$	—	$	—
	US Treasury Bills and Notes		43,296		—		43,296		—
	Total	$	98,865	$	55,569	$	43,296	$	—


	The following tables summarize the Company’s marketable securities at December 31, 2014 and 2013:

		December 31, 2014
				Gross		Gross
		Amortized		Unrealized		Unrealized
	Description	Cost		Gains		Losses		Fair Value
		(in thousands)
	US Treasury Bills and Notes (due within 1 year)	$	165,232	$	28	$	—	$	165,260
	Total	$	165,232	$	28	$	—	$	165,260

		December 31, 2013
				Gross		Gross
		Amortized		Unrealized		Unrealized
	Description	Cost		Gains		Losses		Fair Value
		(in thousands)
	US Treasury Bills and Notes (due within 1 year)	$	2,001	$	1	$	—	$	2,002
	US Treasury Bills and Notes (due after 1 year through 2 years)		41,292		2		—		41,294
	Total	$	43,293	$	3	$	—	$	43,296

	As of December 31, 2014 and 2013, the Company's cash equivalents and short-term investments have been initially valued at the transaction price and subsequently valued utilizing a third party pricing service. The Company validates the prices provided by its third-party pricing service by understanding the models used and obtaining market values from other pricing sources.

	The Company classifies its investments with maturities beyond one year as short-term, based on their highly liquid nature and because such marketable securities represent the investment of cash that is available for current operations.

	The carrying amounts reflected in the consolidated balance sheets for cash, cash equivalents, accounts receivable, other current assets, accounts payable and accrued expenses and other current liabilities approximate fair value due to their short-term maturities.

Inventory

Inventory	12 Months Ended
Inventory	Dec. 31, 2014
Inventory Disclosure [Abstract]
INVENTORY	5. Inventory

	Costs associated with the manufacture of KALBITOR are recorded as inventory.

	Inventory that will be sold beyond the Company's normal operating cycle is classified as non-current and grouped with Other Assets on the Company's consolidated balance sheet. As of December 31, 2014 and 2013, approximately $2.7 million and $5.5 million of inventory, respectively, is classified as non-current.

	KALBITOR product costs of $400,000 associated with an alternative manufacturing process have been capitalized as inventory, as the process is expected to be approved by the FDA and the product would be sold in the future.

	Inventory consists of the following:

		December 31,
		2014		2013
		(in thousands)
	Raw Materials	$	1,074	$	1,116
	Work in Progress		3,872		5,965
	Finished Goods		2,282		1,281
	Total	$	7,228	$	8,362

Fixed_Assets

Fixed Assets	12 Months Ended
Fixed Assets	Dec. 31, 2014
Property Plant And Equipment [Abstract]
FIXED ASSETS	6. Fixed Assets

	Fixed assets consist of the following:

		December 31,
		2014		2013
		(In thousands)
	Laboratory equipment	$	4,134	$	3,932
	Furniture and office equipment		944		815
	Software and computers		3,071		2,958
	Leasehold improvements		4,554		4,510
	Total		12,703		12,215
	Less: accumulated depreciation and amortization		-8,072		-7,255
		$	4,631	$	4,960

	Depreciation expense for the years ended December 31, 2014, 2013, and 2012 was approximately $868,000, $859,000 and $1.1 million, respectively.

	During 2014 and 2013, the Company retired fixed assets of $53,000 and $7.0 million, which had no remaining net book value.

Accounts_Payable_and_Accrued_E

Accounts Payable and Accrued Expenses	12 Months Ended
Accounts Payable and Accrued Expenses	Dec. 31, 2014
Payables And Accruals [Abstract]
ACCOUNTS PAYABLE AND ACCRUED EXPENSES	7. Accounts Payable and Accrued Expenses

	Accounts payable and accrued expenses consist of the following:

		December 31,
		2014		2013
		(In thousands)
	Accounts payable	$	999	$	1,407
	Accrued employee compensation and related taxes		5,759		4,609
	Accrued external research and development and sales expense		3,020		1,778
	Accrued license fees		3,165		348
	Accrued legal		262		456
	Accrued sales allowances		2,368		1,918
	Other accrued liabilities		1,800		2,026
		$	17,373	$	12,542

Longterm_Obligations

Long-term Obligations	12 Months Ended
Long-term Obligations	Dec. 31, 2014
Debt Disclosure [Abstract]
Long-term Obligations	8. Long-term Obligations

	Long-term obligations and note payable consists of the following:

			December 31,
			2014			2013
			(In thousands)
	Note payable		$	82,165		$	81,516
	Obligations under equipment loan			—			931
	Total			82,165			82,447
	Less: current portion			—			-468
	Long-term obligations		$	82,165		$	81,979

	Estimated future payments under the Company's note payable as of December 31, 2014, are as follows:

			(In thousands)
	2015		$	10,327
	2016			11,812
	2017			27,192
	2018			70,778
	2019 and thereafter			—
	Total estimated future payments			120,109
	Less: amount representing interest			-35,637
	Present value of estimated future payments			84,472
	Less: current portion			—
	Less: unamortized portion of discount and deferred interest expense			-2,307
	Long-term obligations and note payable		$	82,165

	These amounts represent projected future principal and interest payments to HealthCare Royalty Partners (HC Royalty) based on current LFRP projections, which are subject to uncertainties based on the timing and amounts of cash receipts under the LFRP. The estimated 2015 amount represents substantially all interest payments. The Company records interest expense on a quarterly basis as incurred and interest payable is recorded on the Company’s consolidated balance sheet as a current liability.

	Note Payable - HealthCare Royalty Partners

	The Company has a loan agreement with an affiliate of HC Royalty with aggregate principal of $84.5 million as of December 31, 2014, consisting of a $22.8 million Tranche A Loan and a $61.7 million Tranche B Loan (collectively, the Loan). The Loan bears interest at a rate of 12% per annum, payable quarterly. The Loan will mature in August 2018, and can be repaid without penalty beginning in August 2015.

	In connection with the Loan, the Company entered into a security agreement granting HC Royalty a security interest in the intellectual property related to the LFRP and the revenues generated by the Company through the licenses of the intellectual property related to the LFRP. The security agreement does not apply to the Company's internal drug development or to any of the Company's co-development programs for ecallantide.

	Under the terms of the agreement, the Company is required to repay the Loan based on the annual net LFRP receipts. Until September 30, 2016, required payments are equal to the sum of 75% of the first $15.0 million in specified annual LFRP receipts and 25% of specified annual LFRP receipts over $15.0 million. After September 30, 2016, and until the maturity date or the complete repayment of the Loan, HC Royalty will receive 90% of all included LFRP receipts. If the HC Royalty portion of LFRP receipts for any quarter exceeds the interest for that quarter, then the principal balance will be reduced. Any unpaid principal will be due upon the maturity of the Loan. If the HC Royalty portion of LFRP revenues for any quarterly period is insufficient to cover the cash interest due for that period, the deficiency may be added to the outstanding principal or paid in cash by the Company. After five years from the dates of the Tranche A Loan and the Tranche B Loan, respectively, the Company must repay to HC Royalty all additional accumulated principal above the original loan amounts of $21.7 million and $58.8 million, respectively.

	Tranche A Loan

	Under the terms of the agreement, the Company received a loan of $20 million (Tranche A Loan) in 2011 and a commitment to refinance amounts outstanding under the Original Loans (defined below) in 2012.

	Upon execution of the Tranche A Loan, the terms of the Original Loans were determined to be modified under ASC 470. During the years ended December 31, 2014, 2013 and 2012, interest expense on the Loan is being recorded in the Company’s financial statements at an effective interest rate of 12.5%, 12.6% and 13.0%, respectively.

	Upon modification of the Original Loans, the note payable balance related to the Tranche A Loan was reduced by $193,000 to reflect payment of the lender’s legal fees in conjunction with the Tranche A Loan; these fees are being accreted over the life of the Loan, through August 2018.

	Tranche B Loan

	In 2012, the Company completed a second closing under the agreement of approximately $57.6 million, the Tranche B loan, which refinanced the Original Loans on the same terms as the Tranche A Loan.

	Original Loans

	In connection with the Original Loans, the Company issued affiliates of HC Royalty warrants to purchase 500,000 shares of the Company’s common stock. In 2008, the Company issued warrants to purchase 250,000 shares of the Company’s common stock at an exercise price of $5.50 per share. This warrant became exercisable in 2009 and could be exercised through August 2016. The Company estimated the relative fair value of the warrant to be $853,000 on the date of issuance, using the Black-Scholes valuation model, assuming a volatility factor of 83.64%, risk-free interest rate of 4.07%, an eight-year expected term and an expected dividend yield of zero. In 2009, the Company issued HC Royalty a second warrant to purchase 250,000 shares of the Company’s common stock at an exercise price of $2.87 per share. This warrant became exercisable in 2010 and could be exercised through August 2016. The Company estimated the relative fair value of the warrant to be $477,000 on the date of issuance, using the Black-Scholes valuation model, assuming a volatility factor of 85.98%, risk-free interest rate of 2.77%, a seven-year, four-month expected term and an expected dividend yield of zero. The relative fair values of the warrants as of the date of issuance are recorded in additional paid-in capital on the Company's consolidated balance sheets. In 2013, HC Royalty executed their right to complete a cashless exercise of their warrants to purchase shares of the Company’s common stock issued in conjunction with the Original Loans. As a result, 233,438 shares were issued to HC Royalty and no warrants remain outstanding under this agreement.

	The cash proceeds from the Original Loans were recorded as a note payable on the Company's consolidated balance sheet. The note payable balance was reduced by $1.3 million for the fair value of the warrants issued, and by $580,000 for payment of HC Royalty’s legal fees in conjunction with the Original Loans. Subsequent to the modification of the debt arrangement in 2011, the unamortized portion of these amounts is being accreted over the life of the Loan through August 2018.


	The Loan principal balance was $84.5 million at December 31, 2014 and 2013. For financial reporting purposes, the Loan is adjusted for discounts associated with the debt issuance, including warrants and fees. Activity under the Loan is presented for financial reporting purposes, as follows:

			2014			2013
			(in thousands)
	Balance, January 1		$	81,516		$	78,061
	Accretion of discount			198			198
	Loan activity:
Interest Expense			10,588			10,447
Payments applied to principal			—			—
Payments applied to interest			-8,978			-5,378
Accrued interest payable			-1,159			-1,812
Balance, December 31		$	82,165		$	81,516

The estimated fair value of the note payable was $83.0 million at December 31, 2014 which was calculated based on level 3 inputs due to the limited availability of comparable data points. The note payable was valued using expected cash flows discounted at our estimate of the currently available market interest rate.

Obligations Under Equipment Loan Arrangements

In 2012, the Company entered into an equipment lease line of credit for up to $3 million with Silicon Valley Bank. When drawn, the note bore interest at a 6% annual rate. The Company drew down $1.4 million from this line during 2012, which was being financed over a 3-year term. As of December 31, 2013, the outstanding balance of this loan was $931,000. The loan was fully paid in September 2014.

Operating Leases

In 2012, the Company relocated its operations to Burlington, Massachusetts. The premises, consisting of approximately 45,000 rentable square feet of office and laboratory facilities, serve as the Company’s principal offices and corporate headquarters. The term of the lease is ten years, and the Company has rights to extend the term for an additional five years at fair market value subject to specified terms and conditions. The aggregate minimum lease commitment over the ten-year term of the new lease is approximately $15.0 million. The Company has provided the landlord a Letter of Credit of $1.1 million to secure its obligations under the lease for which the Company has restricted cash recorded in the accompanying consolidated balance sheet. Under the terms of the lease agreement, the landlord has provided the Company with a tenant improvement allowance of $2.6 million, and a loan totaling $671,000, which was used towards the cost of leasehold improvements. As of December 31, 2014 and 2013 the outstanding balance of the loan was $527,000 and $580,000. The Company has capitalized approximately $4.5 million in leasehold improvements associated with the Burlington facility. Costs reimbursed under the tenant improvement allowance have been recorded as deferred rent and are being amortized as a reduction to rent expense over the lease term.

Gross minimum future lease payments under the Company's non-cancelable operating leases as of December 31, 2014 are as follows:

		(In thousands)
2015		$	1,613
2016			1,693
2017			1,701
2018			1,764
2019			1,678
Thereafter			3,674
Total		$	12,123

Rent expense for the years ended December 31, 2014, 2013, and 2012 was approximately $1.5 million, $1.5 million and $1.6 million, respectively.

Restructuring_Charges

Restructuring Charges	12 Months Ended
Restructuring Charges	Dec. 31, 2014
Disclosure Text Block [Abstract]
Restructuring Charges	9. Restructuring Charges

	In 2012, the Company realigned its business structure and implemented a number of strategic and operational initiatives. As part of these initiatives, a workforce reduction was implemented. As a result of the restructuring, during the year ended December 31, 2012, the Company recorded charges of approximately $1.4 million, which included severance and benefits related charges of approximately $1.2 million, outplacement costs of approximately $120,000, stock compensation expense of $55,000 for amendments to the exercise schedules to certain options and other exit costs of $90,000. All restructuring costs were paid as of December 31, 2012.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stockholders' Equity	10. Stockholders' Equity

	Sale of Common and Preferred Stock

	In March 2014, the Company issued 9,200,000 shares of common stock at $9.25 per share in an underwritten public offering. Net proceeds from the offering were approximately $79.7 million, after deducting offering expenses.

	In October 2013, the Company issued 10,615,385 shares of common stock at $6.50 per share in an underwritten public offering. Net proceeds from the offering were approximately $64.7 million, after deducting offering expenses.

	In May 2013, the Company issued 8,901,675 shares of common stock at $2.30 per share and 41,418 shares of Series 1 convertible preferred stock at $230 per share in a registered direct offering. Each share of Series 1 convertible preferred stock was convertible into 100 shares of common stock, provided, however, that the holder was prohibited from converting Series 1 convertible preferred stock into shares of common stock if, as a result of such conversion, the holder, together with affiliates, would own more than 9.99% of the total shares of the Company’s common stock then issued and outstanding. Net proceeds from the offering were approximately $29.1 million, after deducting offering expenses. In February 2014, all shares of preferred stock outstanding were converted into 4,141,800 shares of common stock. The Company has no remaining preferred stock outstanding.

	Equity Incentive Plan

	The Company's 1995 Equity Incentive Plan (the Equity Plan), as amended, is an equity plan under which equity awards, including awards of restricted stock, restricted stock units (RSUs) and incentive and nonqualified stock options to purchase shares of common stock may be granted to employees, consultants and directors of the Company by action of the Compensation Committee of the Board of Directors. Options are granted at the current fair market value on the date of grant, generally vest ratably over a 48-month period, and expire within ten years from date of grant. RSUs are valued at the current fair market value on the date of grant, and generally vest annually in equal installments over a four-year period. The Equity Plan is intended to attract and retain employees and to provide an incentive for employees, consultants and directors to assist the Company to achieve long-range performance goals and to enable them to participate in the long-term growth of the Company.

	In February 2014, the Company’s Board of Directors amended the Equity Plan to increase the number of shares of common stock approved for issuance under the plan and this amendment was approved by the Company’s stockholders in May 2014. At December 31, 2014, a total of 10,372,949 shares were available for future grants under the Equity Plan.

	Employee Stock Purchase Plan

	The Company's 1998 Employee Stock Purchase Plan (the Purchase Plan) allows employees to purchase shares of the Company's common stock at a discount from fair market value. Under the Purchase Plan, eligible employees may purchase shares during six-month offering periods commencing on June 1 and December 1 of each year at a price per share of 85% of the lower of the fair market value price per share on the first or last day of each six-month offering period. Participating employees may elect to have up to 10% of their base pay withheld and applied toward the purchase of such shares, subject to the limitation of 875 shares per participant per quarter. The rights of participating employees under the Purchase Plan terminate upon voluntary withdrawal from the Purchase Plan at any time or upon termination of employment. In February 2014, the Company’s Board of Directors amended the Purchase Plan to increase the number of shares of common stock approved for issuance under the plan and this amendment was approved by the Company’s stockholders in May 2014.

	The compensation expense recognized in connection with the Plan for the years ended December 31, 2014, 2013 and 2012 was approximately $ 176,000, $310,000 and $91,000, respectively. There were 65,208, 94,979 and 93,974 shares purchased under the Plan during the years ended December 31, 2014, 2013 and 2012, respectively. At December 31, 2014, a total of 702,752 shares were reserved and available for issuance under this Plan.

	Stock-Based Compensation Expense

	The Company measures compensation cost for all stock awards at fair value on date of grant and recognition of compensation over the service period for awards expected to vest. The fair value of stock options was determined using the Black-Scholes valuation model. Such value is recognized as expense over the service period, net of estimated forfeitures and adjusted for actual forfeitures. The estimation of stock options that will ultimately vest requires significant judgment. The Company considers many factors when estimating expected forfeitures, including historical experience. Actual results and future changes in estimates may differ substantially from the Company's current estimates.

	The following table reflects stock compensation expense recorded, net of amounts capitalized into inventory:

			Year Ended December 31,
			2014			2013			2012
			(in thousands)
	Compensation expense related to:
	Equity incentive plan		$	7,107		$	5,131		$	3,549
	Employee stock purchase plan			176			310			91
			$	7,283		$	5,441		$	3,640
	Stock-based compensation expense charged to:
	Research and development		$	2,788		$	1,671		$	839

	Selling, general and administrative		$	4,495		$	3,770		$	2,746

	Restructuring charges		$	—		$	—		$	55

	Stock-based compensation of $69,000, $9,000 and $23,000, which has been excluded from the chart above, was capitalized into inventory for the each of the years ended December 31, 2014, 2013 and 2012, respectively. Capitalized stock-based compensation is recognized into cost of product sales when the related product is sold.

	Stock-based compensation expense for the year ended December 31, 2014, 2013 and 2012 included $77,000, $1.6 million and $467,000, respectively, related to the modification of certain stock options. The 2013 expense included $1.1 million recognized in relation to the extension of exercisability and vesting of options held by a former executive officer.

	Valuation Assumptions for Stock Options

	For the years ended December 31, 2014, 2013 and 2012, 2,899,459, 3,617,150 and 5,897,221 stock options were granted, respectively. The fair value of each option was estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:

			Year Ended December 31,
			2014		2013		2012
	Expected Option Term (in years)		8-Jun		6 – 8		6 – 8
	Risk-free interest rate		1.9% - 2.47%		0.99% - 2.21%		0.86% - 1.37%
	Expected dividend yield		0		0		0
	Volatility factor		66% - 72%		70% - 73%		70% - 73%


	Valuation Assumptions for Employee Stock Purchase Plans

	The fair value of shares issued under the employee stock purchase plan was estimated on the commencement date of each offering period using the Black-Scholes option-pricing model with the following assumptions:

			Year Ended December 31,
			2014		2013		2012
Expected Option Term (in years)		0.5		0.5		0.5
Risk-free interest rate		0.04% - 0.07%		0.06% - 0.10%		0.09% - 0.12%
Expected dividend yield		0		0		0
Volatility factor		47% - 68%		46% - 81%		45% - 54%

Expected volatilities are based on historical volatilities of our common stock; the expected life represents the weighted average period of time that options granted are expected to be outstanding giving consideration to vesting schedules and our historical exercise and cancellation patterns; and the risk-free rate is based on the United States Treasury yield curve in effect at the time of grant for periods corresponding with the expected life of the option.

Stock Option Activity

The following table summarizes stock option activity for the year ended December 31, 2014:


		Number of		Weighted-Avg.			Weighted-Avg.		Aggregate
		Options		Exercise Price			Remaining		Intrinsic Value
							Contractual Life		(in thousands)
Outstanding as of December 31, 2013		10,628,879		$	2.47		6.99		$	53,978
Granted at fair market value		2,899,459		$	9.61
Exercised		-1,448,810		$	2.63
Forfeited		-455,046		$	5.05
Expired		-37,403		$	10.98
Outstanding as of December 31, 2014		11,587,079		$	4.11		6.85		$	115,324

Exercisable as of December 31, 2014		7,055,503		$	2.84		5.8		$	79,179

Vested and unvested expected to vest as of December 31, 2014		11,573,431		$	4.11		6.84		$	115,156

The aggregate intrinsic value in the table above represents the total intrinsic value of the options outstanding, options exercisable and options vested and unvested which are expected to vest, based on the Company’s common stock closing price of $14.06 as of December 31, 2014, which would have been received by the option holders had all option holders exercised their options and sold the underlying common stock as of that date.

The weighted average grant date fair values of options, as determined under ASC 718, granted during the years ended December 31, 2014, 2013 and 2012 were $6.16, $2.06 and $1.00 per share, respectively. The total intrinsic value of options exercised during years ended December 31, 2014, 2013 and 2012 was approximately $10.9 million, $5.4 million, and $375,000, respectively. The total cash received from employees as a result of employee stock option exercises during the years ended December 31, 2014, 2013 and 2012 was approximately $3.8 million, $5.1 million, and $1.3 million, respectively.

As of December 31, 2014 future compensation cost related to non-vested stock options is approximately $19.2 million and will be recognized over an estimated weighted average period of approximately 2.42 years.


Restricted Stock Unit Activity

The fair market value of RSUs is expensed over the period of vesting. RSUs generally vest over a four-year period in equal installments on each anniversary of the grant date. The fair value of RSUs was determined based on the closing market price of the underlying stock on the grant date. The following table summarizes our RSU activity:

		Number of	Weighted-Avg.					Aggregate
		Shares	Remaining					Intrinsic Value
			Contractual Life					(in thousands)
Unvested as of December 31, 2013		253,124			1.48
Granted		368,541
Vested		-101,877
Forfeited		-33,614
Unvested as of December 31, 2014		486,174			1.36		$	6,836

Vested and unvested expected to vest as of December 31, 2014		419,036			1.24		$	5,892

Exercisable as of December 31, 2014		—			—		$	—

As of December 31, 2014, there was $2.3 million of total unrecognized compensation cost related to unvested restricted stock units. This expense, net of forfeitures, is expected to be recognized over a weighted average period of approximately 2.53 years.

Employee_Savings_and_Retiremen

Employee Savings and Retirement Plans	12 Months Ended
Employee Savings and Retirement Plans	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Employee Savings and Retirement Plan	11. Employee Savings and Retirement Plans

	The Company has an employee savings and retirement plan (the "Retirement Plan"), qualified under Section 401(k) of the Internal Revenue Code, covering substantially all of the Company's employees. Employees may elect to contribute a portion of their pretax compensation to the Retirement Plan up to the annual maximum allowed under the Retirement Plan. Employees are 100% vested in company matching contributions which have been 50% of employee contributions up to 6% of eligible pay. For the years ended December 31, 2014, 2013 and 2012, the Company's matching contributions amounted to $441,000, $451,000 and $440,000, respectively.

Income_Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes

	Deferred tax assets and deferred tax liabilities are recognized based on temporary differences between the financial reporting and tax basis of assets and liabilities using future enacted rates. A valuation allowance is recorded against deferred tax assets for which the Company determines that it does not meet the criteria under ASC 740.

	The provision for income taxes for continuing operations was calculated at rates different from the United States federal statutory income tax rate for the following reasons: .

			2014		2013		2012
	Statutory federal income taxes		34	%	34	%	34	%
	State income taxes, net of federal benefit		-14.3	%	-4.7	%	-3.3	%
	General business credit		36.2	%	4.5	%	3.8	%
	Stock compensation, including cancellations		-9	%	-0.8	%	-6.8	%
	Other		-0.4	%	1.6	%	-1.7	%
	Federal true up and expiring NOLs and research credits		2.7	%	0.4	%	-8.6	%
	Valuation allowance		-49.2	%	-35	%	-17.4	%
	Effective income tax rate		—	%	—	%	—	%

	The principal components of the Company's deferred tax assets and liabilities are as follows:

			2014		2013			2012
			(In thousands)
	Net Deferred Tax Asset:
	Depreciation and amortization	$	204		$	228		$	255
	Accrued expenses		398			642			303
	Capitalized research and development costs		21,537			23,603			8,192
	Other		1,217			1,339			1,394
	Stock based compensation		3,241			2,575			2,127
	Deferred revenue		2,569			2,928			4,223
	Research credit carryforwards		73,893			67,088			63,259
	Net operating loss carryforwards		116,719			115,531			124,507
	Total gross deferred tax asset		219,778			213,934			204,260
	Valuation allowance		-219,778			-213,934			-204,260
	Net deferred tax asset	$	—		$	—		$	—

	As of December 31, 2014 and 2013, the Company had federal tax net operating loss carryforwards (NOLs) of $348.1 million and $329.2 million, respectively, available to reduce future taxable income, which expire at various times beginning in 2018 through 2034. The Company also had federal research and experimentation and orphan drug credit carryforwards of approximately $68.1 million and $61.6 million as of December 31 2014 and 2013, respectively, available to reduce future tax liabilities which will expire at various dates beginning in 2018 through 2034. The Company had state tax net operating loss carryforwards of approximately $53.5 million and $93.8 million as of December 31, 2014 and 2013, respectively, available to reduce future state taxable income, which will expire at various dates beginning in 2029 through 2034. The Company had state NOLs related to stock compensation in the amount of $5.5 million that is not included in the deferred tax asset. The Company also had state research and development and investment tax credit carryforwards of approximately $8.8 million and $8.3 million as of December 31, 2014 and 2013, respectively, available to reduce future tax liabilities which expire at various dates beginning in 2015 through 2029.

	Included in the NOL carryforward of $348.1 million and $329.2 million are approximately $16.7 million and $8.2 million of tax deductions from the exercise of stock options at December 31, 2014 and 2013, respectively. The Company has also recorded a deferred tax asset of approximately $1.8 million at both December 31, 2014 and 2013 reflecting the benefit of the deduction from the exercise of stock options which has been fully reserved until it is more likely than not that the benefit will be realized. The benefit from these deductions will be recorded as a credit to additional paid-in capital if and when realized through a reduction of taxes paid in cash.

	As required by ASC 740, management of the Company has evaluated the positive and negative evidence bearing upon the reliability of its deferred tax assets, which are comprised principally of NOL carry forwards, research and experimentation credit carryforwards, and capitalized start up expenditures and research and development expenditures amortizable over ten years straight-line. Management has determined at this time that it is more likely than not that the Company will not recognize the benefits of its federal and state deferred tax assets and, as a result, a valuation allowance of approximately $219.8 million and $213.9 million has been established at December 31, 2014 and 2013, respectively.

	The Company accounts for uncertain tax positions using a "more-likely-than-not" threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors that include, but are not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The Company evaluates uncertain tax positions on a quarterly basis and adjusts the level of the liability to reflect any subsequent changes in the relevant facts surrounding the uncertain positions. As of December 31, 2014, the Company had no unrecognized tax benefits or liabilities and had no accrued interest or penalties related to uncertain tax positions.

	Utilization of the NOLs and tax credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that have occurred previously or that could occur in the future, as provided by Section 382 of the Internal Revenue Code of 1986 (Section 382), as well as similar state and foreign provisions. Ownership changes may limit the amount of NOLs and tax credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an ownership change, as defined by Section 382, results from transactions that increase the ownership of 5% shareholders or public groups in the stock of a corporation by more than 50 percent in the aggregate over a three-year period. The Company has completed studies through December 31, 2013, to determine whether any ownership change has occurred since the Company's formation and has determined that transactions have resulted in two ownership changes, as defined by Section 382. There could be additional ownership changes in the future that could further limit the amount of NOLs and tax credit carryforwards that the Company can utilize.

	As of December 31, 2013, the Company’s federal tax NOLs available to reduce future taxable income without limitation are $260.6 million, which expire at various times beginning in 2024 through 2033. The Company’s federal research and experimentation and orphan drug credit carryforward as of December 31, 2013 available to reduce future tax liabilities without limitation are $56.8 million, which will expire at various dates beginning in 2024 through 2033. In addition the Company has NOL and federal tax credits that are restricted and expire at various times beginning in 2018 through 2024. These restricted NOLs and federal tax credits of $67.2 million and $4.8 million, respectively, may be utilized in part, subject to an annual limitation. Ownership changes after December 31, 2013 could further restrict the use of these NOLs and federal tax credits.

	A full valuation allowance has been provided against the Company's NOL carryforwards and research and development credits and, if an adjustment is required, this adjustment would be offset by an adjustment to the valuation allowance. Thus there would be no impact to the consolidated balance sheet or statement of operations if an adjustment were required.

	The tax years 2000 through 2014 remain open to examination by major taxing jurisdictions to which the Company is subject, which are primarily in the United States, as carryforward attributes generated in years past may still be adjusted upon examination by the Internal Revenue Service or state tax authorities if they have or will be used in a future period. The Company is currently not under examination in any jurisdictions for any tax years.

Litigation_and_Contingencies

Litigation and Contingencies	12 Months Ended
Litigation and Contingencies	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Litigation and Contingencies	13. Litigation and Contingencies

	As of December 31, 2014, there were no active legal proceedings that were expected to be material to the Company. The Company makes provisions for claims specifically identified for which it believes the likelihood of an unfavorable outcome is probable and reasonably estimable. The Company records at least the minimum estimated liability related to claims where there is a range of loss and the loss is considered probable and no estimate within the range is better than any other. As additional information becomes available, the Company assesses the potential liability related to its pending claims and revises its estimates. Future revisions in the estimates of the potential liability could materially impact the results of operations and financial position. The Company maintains insurance coverage that limits the exposure for any single claim as well as total amounts incurred per policy year, and it believes that its insurance coverage is adequate. The Company makes every effort to use the best information available in determining the level of liability reserves.

	In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners, and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company does not believe that the outcome of any claims under indemnification arrangements will have a material effect on its financial position, results of operations or cash flows, and it has not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2014.

Unaudited_Quarterly_Operating_

Unaudited Quarterly Operating Results	12 Months Ended
Unaudited Quarterly Operating Results	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Operating Results	14. Unaudited Quarterly Operating Results

	The following is a summary of unaudited quarterly and annual results of operations for the years ended December 31, 2014 and 2013:

		First		Second		Third		Fourth
	Year ended December 31, 2014	Quarter		Quarter		Quarter		Quarter		Total Year
		(in thousands, except share and per share)
	Revenue	$	14,117	$	19,585	$	21,993	$	26,028	$	81,723
	Income (loss) from operations	$	-3,026	$	-411	$	1,858	$	344	$	-1,235
	Net loss	$	-5,711	$	-3,061	$	-816	$	-2,290	$	-11,878
	Shares used in computing basic and diluted net loss per share		124,618,519		135,873,613		136,282,842		136,533,907		133,367,963
	Basic and diluted net loss per share:	$	-0.05	$	-0.02	$	-0.01	$	-0.02	$	-0.09

		First		Second		Third		Fourth
	Year ended December 31, 2013	Quarter		Quarter		Quarter		Quarter		Total Year
		(in thousands, except share and per share)
	Revenue	$	12,040	$	11,336	$	13,691	$	16,859	$	53,926
	Income (loss) from operations	$	-8,463	$	-5,850	$	-3,641	$	755	$	-17,199
	Net loss	$	-11,193	$	-8,432	$	-6,188	$	-1,964	$	-27,777
	Shares used in computing basic and diluted net loss per share		99,644,227		104,977,247		109,731,276		119,573,601		108,539,613
	Basic and diluted net loss per share:	$	-0.11	$	-0.08	$	-0.06	$	-0.02	$	-0.26

Accounting_Policies_Policies

Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2014

Accounting Policies [Abstract]

Basis of Consolidation

Use of Estimates

Concentration of Credit Risk

Cash and Cash Equivalents

Investments

Inventories

Fixed Assets

Impairment of Long-Lived Assets

Revenue Recognition

Product Sales and Allowances

Under certain arrangements the Company has provided their distributors with extended payment terms. In these circumstances, revenue is not recognized until collectability is reasonably assured.

Fees paid to distributors for inventory maintenance are calculated as a percentage of KALBITOR sales price and accordingly, are classified as a reduction in product sales revenue.

An analysis of the amount of, and change in, reserves related to sales allowances is summarized as follows:

Prompt pay

Government

and other

Patient financial

rebates and

(In thousands)

discounts

assistance

chargebacks

Returns

Total

Balance, as of December 31, 2012

388

165

565

551

1,669

Current provisions relating to sales in current year

2,565

498

2,806

145

6,014

Adjustments relating to prior years

-38

-79

-141

-235

Payments relating to sales in current year

-2,165

-378

-1,380

—

-3,923

Payments/returns relating to sales in prior years

-327

-157

-278

-232

-994

Balance, as of December 31, 2013

484

1,634

323

2,531

Current provisions relating to sales in current year

3,593

443

3,270

267

7,573

Adjustments relating to prior years

-209

-148

Payments relating to sales in current year

-3,154

-385

-1,800

—

-5,339

Payments/returns relating to sales in prior years

-383

-16

-908

-42

-1,349

Balance, as of December 31, 2014

546

143

1,987

592

3,268

Development and License Fee Revenues

Eliminate the use of the residual method and require an entity to allocate arrangement consideration using the selling price hierarchy.

LFRP Milestones

The Company recognized revenue of approximately $4.5 million, $3.1 million and $3.3 million related to milestones under the LFRP for the years ended December 31, 2014, 2013 and 2012, respectively.

Non-LFRP Milestones

Royality Revenues

Royalty Revenue

Cost of Product Sales and Royalties

Cost of royalties is derived from pass-through fees under the Company’s cross license agreement related to royalties from product sales by its LFRP licensees.

Research and Development

Income Taxes

Translation of Foreign Currencies

Share-Based Compensation

Income or Loss Per Share

The weighted average of stock options, restricted stock units and warrants outstanding totaled 12.2 million, 12.2 million and 12.3 million at December 31, 2014, 2013, and 2012, respectively.

Comprehensive Income (Loss)

Business Segments

Recent Accounting Pronouncements

Accounting_Policies_Tables

Accounting Policies (Tables)	12 Months Ended
Accounting Policies (Tables)	Dec. 31, 2014
Accounting Policies [Abstract]
Reserves Related to Sales Allowances	An analysis of the amount of, and change in, reserves related to sales allowances is summarized as follows:

		Prompt pay				Government
		and other		Patient financial		rebates and
	(In thousands)	discounts		assistance		chargebacks		Returns		Total
	Balance, as of December 31, 2012	$	388	$	165	$	565	$	551	$	1,669
	Current provisions relating to sales in current year		2,565		498		2,806		145		6,014
	Adjustments relating to prior years		23		-38		-79		-141		-235
	Payments relating to sales in current year		-2,165		-378		-1,380		—		-3,923
	Payments/returns relating to sales in prior years		-327		-157		-278		-232		-994
	Balance, as of December 31, 2013		484		90		1,634		323		2,531
	Current provisions relating to sales in current year		3,593		443		3,270		267		7,573
	Adjustments relating to prior years		6		11		-209		44		-148
	Payments relating to sales in current year		-3,154		-385		-1,800		—		-5,339
	Payments/returns relating to sales in prior years		-383		-16		-908		-42		-1,349
	Balance, as of December 31, 2014	$	546	$	143	$	1,987	$	592	$	3,268

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
Fair Value Measurements (Tables)	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Financial Assets Measured at Fair Value	Fair values determined by Level 3 inputs are unobservable data points for the asset or liability, and includes situations where there is little, if any, market activity for the asset or liability.

				Quoted		Significant
				Prices in		Other		Significant
		December		Active		Observable		Unobservable
		31,		Markets		Inputs		Inputs
	Description	2014		(Level 1)		(Level 2)		(Level 3)
		(in thousands)
	Assets:
	Money Market Funds	$	15,610	$	15,610	$	—	$	—
	US Treasury Bills and Notes		165,260		—		165,260		—
	Total	$	180,870	$	15,610	$	165,260	$	—

				Quoted		Significant
				Prices in		Other		Significant
		December		Active		Observable		Unobservable
		31,		Markets		Inputs		Inputs
	Description	2013		(Level 1)		(Level 2)		(Level 3)
		(in thousands)
	Assets:
	Money Market Funds	$	55,569	$	55,569	$	—	$	—
	US Treasury Bills and Notes		43,296		—		43,296		—
	Total	$	98,865	$	55,569	$	43,296	$	—

Marketable Securities	The following tables summarize the Company’s marketable securities at December 31, 2014 and 2013:

		December 31, 2014
				Gross		Gross
		Amortized		Unrealized		Unrealized
	Description	Cost		Gains		Losses		Fair Value
		(in thousands)
	US Treasury Bills and Notes (due within 1 year)	$	165,232	$	28	$	—	$	165,260
	Total	$	165,232	$	28	$	—	$	165,260

		December 31, 2013
				Gross		Gross
		Amortized		Unrealized		Unrealized
	Description	Cost		Gains		Losses		Fair Value
		(in thousands)
	US Treasury Bills and Notes (due within 1 year)	$	2,001	$	1	$	—	$	2,002
	US Treasury Bills and Notes (due after 1 year through 2 years)		41,292		2		—		41,294
	Total	$	43,293	$	3	$	—	$	43,296

Inventory_Tables

Inventory (Tables)	12 Months Ended
Inventory (Tables)	Dec. 31, 2014
Inventory Disclosure [Abstract]
Components of Inventory	Inventory consists of the following:

		December 31,
		2014		2013
		(in thousands)
	Raw Materials	$	1,074	$	1,116
	Work in Progress		3,872		5,965
	Finished Goods		2,282		1,281
	Total	$	7,228	$	8,362

Fixed_Assets_Tables

Fixed Assets (Tables)	12 Months Ended
Fixed Assets (Tables)	Dec. 31, 2014
Property Plant And Equipment [Abstract]
Components of Fixed Assets	Fixed assets consist of the following:

		December 31,
		2014		2013
		(In thousands)
	Laboratory equipment	$	4,134	$	3,932
	Furniture and office equipment		944		815
	Software and computers		3,071		2,958
	Leasehold improvements		4,554		4,510
	Total		12,703		12,215
	Less: accumulated depreciation and amortization		-8,072		-7,255
		$	4,631	$	4,960

Accounts_Payable_and_Accrued_E1

Accounts Payable and Accrued Expenses (Tables)	12 Months Ended
Accounts Payable and Accrued Expenses (Tables)	Dec. 31, 2014
Payables And Accruals [Abstract]
Components of Accounts Payable and Accrued Expenses	Accounts payable and accrued expenses consist of the following:

		December 31,
		2014		2013
		(In thousands)
	Accounts payable	$	999	$	1,407
	Accrued employee compensation and related taxes		5,759		4,609
	Accrued external research and development and sales expense		3,020		1,778
	Accrued license fees		3,165		348
	Accrued legal		262		456
	Accrued sales allowances		2,368		1,918
	Other accrued liabilities		1,800		2,026
		$	17,373	$	12,542

Longterm_Obligations_Tables

Long-term Obligations (Tables)	12 Months Ended
Long-term Obligations (Tables)	Dec. 31, 2014
Debt Disclosure [Abstract]
Long-Term Obligations and Note Payable	Long-term obligations and note payable consists of the following:

		December 31,
		2014		2013
		(In thousands)
	Note payable	$	82,165	$	81,516
	Obligations under equipment loan		—		931
	Total		82,165		82,447
	Less: current portion		—		-468
	Long-term obligations	$	82,165	$	81,979

Minimum Future Payments under Long-Term Obligations and Note Payable	Estimated future payments under the Company's note payable as of December 31, 2014, are as follows:

		(In thousands)
	2015	$	10,327
	2016		11,812
	2017		27,192
	2018		70,778
	2019 and thereafter		—
	Total estimated future payments		120,109
	Less: amount representing interest		-35,637
	Present value of estimated future payments		84,472
	Less: current portion		—
	Less: unamortized portion of discount and deferred interest expense		-2,307
	Long-term obligations and note payable	$	82,165

Activity under Loan Presented for Financial Reporting Purposes	Activity under the Loan is presented for financial reporting purposes, as follows:

		2014		2013
		(in thousands)
	Balance, January 1	$	81,516	$	78,061
	Accretion of discount		198		198
	Loan activity:
	Interest Expense		10,588		10,447
	Payments applied to principal		—		—
	Payments applied to interest		-8,978		-5,378
	Accrued interest payable		-1,159		-1,812
	Balance, December 31	$	82,165	$	81,516

Gross Minimum Future Lease Payments under Non-Cancelable Operating Leases	Gross minimum future lease payments under the Company's non-cancelable operating leases as of December 31, 2014 are as follows:

		(In thousands)
	2015	$	1,613
	2016		1,693
	2017		1,701
	2018		1,764
	2019		1,678
	Thereafter		3,674
	Total	$	12,123

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
Stockholders' Equity (Tables)	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Compensation Expense	The following table reflects stock compensation expense recorded, net of amounts capitalized into inventory:

		Year Ended December 31,
		2014			2013			2012
		(in thousands)
	Compensation expense related to:
	Equity incentive plan	$	7,107		$	5,131		$	3,549
	Employee stock purchase plan		176			310			91
		$	7,283		$	5,441		$	3,640
	Stock-based compensation expense charged to:
	Research and development	$	2,788		$	1,671		$	839

	Selling, general and administrative	$	4,495		$	3,770		$	2,746

	Restructuring charges	$	—		$	—		$	55

Fair Value of Option	The fair value of each option was estimated on the date of grant using the Black-Scholes option-pricing model with the following assumptions:

		Year Ended December 31,
		2014		2013		2012
	Expected Option Term (in years)	8-Jun		6 – 8		6 – 8
	Risk-free interest rate	1.9% - 2.47%		0.99% - 2.21%		0.86% - 1.37%
	Expected dividend yield	0		0		0
	Volatility factor	66% - 72%		70% - 73%		70% - 73%

Fair Value of Shares Issued under Employee Stock Purchase Plan	The fair value of shares issued under the employee stock purchase plan was estimated on the commencement date of each offering period using the Black-Scholes option-pricing model with the following assumptions:

		Year Ended December 31,
		2014		2013		2012
	Expected Option Term (in years)	0.5		0.5		0.5
	Risk-free interest rate	0.04% - 0.07%		0.06% - 0.10%		0.09% - 0.12%
	Expected dividend yield	0		0		0
	Volatility factor	47% - 68%		46% - 81%		45% - 54%

Stock Options Activity	The following table summarizes stock option activity for the year ended December 31, 2014:


		Number of		Weighted-Avg.			Weighted-Avg.		Aggregate
		Options		Exercise Price			Remaining		Intrinsic Value
							Contractual Life		(in thousands)
	Outstanding as of December 31, 2013	10,628,879		$	2.47		6.99		$	53,978
	Granted at fair market value	2,899,459		$	9.61
	Exercised	-1,448,810		$	2.63
	Forfeited	-455,046		$	5.05
	Expired	-37,403		$	10.98
	Outstanding as of December 31, 2014	11,587,079		$	4.11		6.85		$	115,324

	Exercisable as of December 31, 2014	7,055,503		$	2.84		5.8		$	79,179

	Vested and unvested expected to vest as of December 31, 2014	11,573,431		$	4.11		6.84		$	115,156

Restricted Stock Unit Activity	The following table summarizes our RSU activity:

		Number of	Weighted-Avg.					Aggregate
		Shares	Remaining					Intrinsic Value
			Contractual Life					(in thousands)
	Unvested as of December 31, 2013	253,124			1.48
	Granted	368,541
	Vested	-101,877
	Forfeited	-33,614
	Unvested as of December 31, 2014	486,174			1.36		$	6,836

	Vested and unvested expected to vest as of December 31, 2014	419,036			1.24		$	5,892

	Exercisable as of December 31, 2014	—			—		$	—

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of Effective Income Tax Rate Reconciliation	The provision for income taxes for continuing operations was calculated at rates different from the United States federal statutory income tax rate for the following reasons: .

			2014		2013		2012
	Statutory federal income taxes		34	%	34	%	34	%
	State income taxes, net of federal benefit		-14.3	%	-4.7	%	-3.3	%
	General business credit		36.2	%	4.5	%	3.8	%
	Stock compensation, including cancellations		-9	%	-0.8	%	-6.8	%
	Other		-0.4	%	1.6	%	-1.7	%
	Federal true up and expiring NOLs and research credits		2.7	%	0.4	%	-8.6	%
	Valuation allowance		-49.2	%	-35	%	-17.4	%
	Effective income tax rate		—	%	—	%	—	%

Schedule of Deferred Tax Assets and Liabilities	The principal components of the Company's deferred tax assets and liabilities are as follows:

			2014		2013			2012
			(In thousands)
	Net Deferred Tax Asset:
	Depreciation and amortization	$	204		$	228		$	255
	Accrued expenses		398			642			303
	Capitalized research and development costs		21,537			23,603			8,192
	Other		1,217			1,339			1,394
	Stock based compensation		3,241			2,575			2,127
	Deferred revenue		2,569			2,928			4,223
	Research credit carryforwards		73,893			67,088			63,259
	Net operating loss carryforwards		116,719			115,531			124,507
	Total gross deferred tax asset		219,778			213,934			204,260
	Valuation allowance		-219,778			-213,934			-204,260
	Net deferred tax asset	$	—		$	—		$	—

Unaudited_Quarterly_Operating_1

Unaudited Quarterly Operating Results (Tables)	12 Months Ended
Unaudited Quarterly Operating Results (Tables)	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Summary of Unaudited Quarterly and Annual Results of Operations	The following is a summary of unaudited quarterly and annual results of operations for the years ended December 31, 2014 and 2013:

		First		Second		Third		Fourth
	Year ended December 31, 2014	Quarter		Quarter		Quarter		Quarter		Total Year
		(in thousands, except share and per share)
	Revenue	$	14,117	$	19,585	$	21,993	$	26,028	$	81,723
	Income (loss) from operations	$	-3,026	$	-411	$	1,858	$	344	$	-1,235
	Net loss	$	-5,711	$	-3,061	$	-816	$	-2,290	$	-11,878
	Shares used in computing basic and diluted net loss per share		124,618,519		135,873,613		136,282,842		136,533,907		133,367,963
	Basic and diluted net loss per share:	$	-0.05	$	-0.02	$	-0.01	$	-0.02	$	-0.09

		First		Second		Third		Fourth
	Year ended December 31, 2013	Quarter		Quarter		Quarter		Quarter		Total Year
		(in thousands, except share and per share)
	Revenue	$	12,040	$	11,336	$	13,691	$	16,859	$	53,926
	Income (loss) from operations	$	-8,463	$	-5,850	$	-3,641	$	755	$	-17,199
	Net loss	$	-11,193	$	-8,432	$	-6,188	$	-1,964	$	-27,777
	Shares used in computing basic and diluted net loss per share		99,644,227		104,977,247		109,731,276		119,573,601		108,539,613
	Basic and diluted net loss per share:	$	-0.11	$	-0.08	$	-0.06	$	-0.02	$	-0.26

Nature_of_Business_Additional_

Nature of Business - Additional Information (Detail) (LFRP, Phase 3 Trials)	12 Months Ended
	Dec. 31, 2014
	Product
LFRP \| Phase 3 Trials
Product Information [Line Items]
Number of products to be developed	3

Accounting_Policies_Additional

Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
Share data in Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Significant Accounting Policies [Line Items]
Available-for-sale investment amortized cost	$165,232,000				$43,293,000				$165,232,000	$43,293,000
Available-for-sale estimated fair value	165,260,000				43,296,000				165,260,000	43,296,000
Unrealized gain on available-for-sale investments	28,000				3,000				28,000	3,000
Stock options and warrants purchase									12.2	12.2	12.3
Revenues	26,028,000	21,993,000	19,585,000	14,117,000	16,859,000	13,691,000	11,336,000	12,040,000	81,723,000	53,926,000	54,650,000
Foreign Exchange
Significant Accounting Policies [Line Items]
Other Expenses									33,000
Other Income										14,000	15,000
Customers Segment Location
Significant Accounting Policies [Line Items]
Percentage of prompt payment discount accrued at the time of sale									100.00%
Standard product warranty description									Although allowances and accruals are recorded at the time of product sale, certain rebates are typically paid out, on average, up to six months or longer after the sale. Reserve estimates are evaluated quarterly and if necessary, adjusted to reflect actual results.
Number of business segment	1
Number of geographic area within which the company operates predominantly	1								1
Not Substantive Milestones
Significant Accounting Policies [Line Items]
Milestones payment receipt									4,500,000	3,100,000	3,300,000
Development Milestones
Significant Accounting Policies [Line Items]
Milestones payment receipt									81,000,000
Regulatory Filing Milestones
Significant Accounting Policies [Line Items]
Milestones payment receipt									67,000,000
Marketing Approval Milestones
Significant Accounting Policies [Line Items]
Milestones payment receipt									96,000,000
Accounts Receivable
Significant Accounting Policies [Line Items]
Number of companies									3	2
Foreign Countries \| Sales Revenue
Significant Accounting Policies [Line Items]
Concentration risk percentage									3.00%	13.00%	13.00%
Maximum
Significant Accounting Policies [Line Items]
Estimated useful life of property plant and equipment									7 years
Minimum
Significant Accounting Policies [Line Items]
Estimated useful life of property plant and equipment									3 years
Walgreens Infusion Services, Inc.
Significant Accounting Policies [Line Items]
Concentration risk percentage									20.00%	26.00%
Walgreens Infusion Services, Inc. \| Sales Revenue
Significant Accounting Policies [Line Items]
Concentration risk percentage									34.00%	38.00%	40.00%
US Bioservices Corporation
Significant Accounting Policies [Line Items]
Concentration risk percentage									21.00%	35.00%
US Bioservices Corporation \| Sales Revenue
Significant Accounting Policies [Line Items]
Concentration risk percentage									28.00%	26.00%	30.00%
Customers \| Substantive Milestones
Significant Accounting Policies [Line Items]
Revenues											327,000
Lilly
Significant Accounting Policies [Line Items]
Concentration risk percentage									27.00%
Unbilled Accounts Receivable	1,700,000								1,700,000
Cash and Cash Equivalents
Significant Accounting Policies [Line Items]
Concentration risk percentage									98.00%	89.00%
Number of financial institution in which financial instruments invested	1								1
Short term investment maturity period									90 days
Short-term Investments \| Maximum
Significant Accounting Policies [Line Items]
Short term investment maturity period									1 year
Short-term Investments \| Minimum
Significant Accounting Policies [Line Items]
Short term investment maturity period									90 days
US Treasury Bills and Notes
Significant Accounting Policies [Line Items]
Available-for-sale investment amortized cost	165,200,000				43,300,000				165,200,000	43,300,000
Available-for-sale estimated fair value	165,300,000								165,300,000
Unrealized gain on available-for-sale investments	$28,000				$3,000				$28,000	$3,000

Reserves_Related_to_Sales_Allo

Reserves Related to Sales Allowances (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Valuation Allowance [Line Items]
Beginning balance	$2,531	$1,669
Current provisions relating to sales in current year	7,573	6,014
Adjustments relating to prior years	-148	-235
Payments relating to sales in current year	-5,339	-3,923
Payments/returns relating to sales in prior years	-1,349	-994
Ending balance	3,268	2,531
Prompt pay and other discounts
Valuation Allowance [Line Items]
Beginning balance	484	388
Current provisions relating to sales in current year	3,593	2,565
Adjustments relating to prior years	6	23
Payments relating to sales in current year	-3,154	-2,165
Payments/returns relating to sales in prior years	-383	-327
Ending balance	546	484
Patient financial assistance
Valuation Allowance [Line Items]
Beginning balance	90	165
Current provisions relating to sales in current year	443	498
Adjustments relating to prior years	11	-38
Payments relating to sales in current year	-385	-378
Payments/returns relating to sales in prior years	-16	-157
Ending balance	143	90
Government rebates and chargebacks
Valuation Allowance [Line Items]
Beginning balance	1,634	565
Current provisions relating to sales in current year	3,270	2,806
Adjustments relating to prior years	-209	-79
Payments relating to sales in current year	-1,800	-1,380
Payments/returns relating to sales in prior years	-908	-278
Ending balance	1,987	1,634
Returns
Valuation Allowance [Line Items]
Beginning balance	323	551
Current provisions relating to sales in current year	267	145
Adjustments relating to prior years	44	-141
Payments relating to sales in current year	0	0
Payments/returns relating to sales in prior years	-42	-232
Ending balance	$592	$323

Significant_Transactions_Addit

Significant Transactions - Additional Information (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2010
Significant Transactions [Line Items]
Revenue	$26,028,000	$21,993,000	$19,585,000	$14,117,000	$16,859,000	$13,691,000	$11,336,000	$12,040,000	$81,723,000	$53,926,000	$54,650,000
Common stock, shares issued	136,662,175				121,704,480				136,662,175	121,704,480
CMIC Co., Ltd, (CMIC)
Significant Transactions [Line Items]
Revenue										2,600,000	755,000
Deferred revenue					2,000,000					2,000,000
CMIC Co., Ltd, (CMIC) \| Up-front Payment Arrangement
Significant Transactions [Line Items]
Collaboration arrangement payment												4,000,000
Sigma Tau
Significant Transactions [Line Items]
Reduction to development and license fee revenue										1,100,000
Deferred revenue, revenue recognized										85,000	204,000
Sigma Tau \| Contract Termination
Significant Transactions [Line Items]
Common stock, shares issued	271,665								271,665
Consideration contractually obligated to pay contingent upon future sales									500,000
Compensation received during the next ten years in relation to the license or supply of ecallantide									5,000,000
Sigma Tau \| Development Services
Significant Transactions [Line Items]
Collaboration arrangement payment									7,000,000
Common stock, shares issued	787,647								787,647
Reimbursement from collaboration arrangement									3,800,000
Common stock aggregate purchase price	3,000,000								3,000,000
CVie Therapeutics
Significant Transactions [Line Items]
Collaboration arrangement receivable									11,000,000
Revenue									105,000	172,000
Deferred revenue	723,000				828,000				723,000	828,000
CVie Therapeutics \| Up-front Payment Arrangement
Significant Transactions [Line Items]
Collaboration arrangement payment									1,000,000
Novellus Plan
Significant Transactions [Line Items]
Deferred revenue					500,000					500,000
Novellus Plan \| Up-front Payment Arrangement
Significant Transactions [Line Items]
Collaboration arrangement payment										500,000
Collaboration arrangement receivable										$5,200,000

Financial_Assets_Measured_at_F

Financial Assets Measured at Fair Value (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	$180,870	$98,865
Quoted Prices in Active Markets (Level 1)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	15,610	55,569
Significant Other Observable Inputs (Level 2)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	165,260	43,296
Significant Unobservable Inputs (Level 3)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	0	0
Money Market Funds
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	15,610	55,569
Money Market Funds \| Quoted Prices in Active Markets (Level 1)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	15,610	55,569
Money Market Funds \| Significant Other Observable Inputs (Level 2)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	0	0
Money Market Funds \| Significant Unobservable Inputs (Level 3)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	0	0
US Treasury Bill Securities
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	165,260	43,296
US Treasury Bill Securities \| Quoted Prices in Active Markets (Level 1)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	0	0
US Treasury Bill Securities \| Significant Other Observable Inputs (Level 2)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	165,260	43,296
US Treasury Bill Securities \| Significant Unobservable Inputs (Level 3)
Financial Assets Measured at Fair Value [Line Items]
Assets fair value disclosure Recurring	$0	$0

Marketable_Securities_Detail

Marketable Securities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Marketable Securities [Line Items]
Amortized Cost	$165,232,000	$43,293,000
Gross Unrealized Gains	28,000	3,000
Gross Unrealized Losses	0	0
Fair Value	165,260,000	43,296,000
Due In One Year Or Less
Marketable Securities [Line Items]
Amortized Cost	165,232,000	2,001,000
Gross Unrealized Gains	28,000	1,000
Gross Unrealized Losses	0	0
Fair Value	165,260,000	2,002,000
Due After One Year Through Two Years
Marketable Securities [Line Items]
Amortized Cost		41,292,000
Gross Unrealized Gains		2,000
Gross Unrealized Losses		0
Fair Value		$41,294,000

Inventory_Additional_Informati

Inventory - Additional Information (Detail) (USD $)	12 Months Ended
Inventory - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Inventory [Line Items]
Production Costs, Period Cost	$400,000
Other Noncurrent Assets
Inventory [Line Items]
Inventory classified as non-current	$2,700,000	$5,500,000

Components_of_Inventory_Detail

Components of Inventory (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Inventory [Line Items]
Raw Materials	$1,074	$1,116
Work in Progress	3,872	5,965
Finished Goods	2,282	1,281
Total	$7,228	$8,362

Fixed_Assets_Additional_Inform

Fixed Assets - Additional Information (Detail) (USD $)	12 Months Ended
Fixed Assets - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fixed Assets [Line Items]
Depreciation expense	$868,000	$859,000	$1,100,000
Fixed assets retirement	$53,000	$7,000,000

Components_of_Fixed_Assets_Det

Components of Fixed Assets (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Fixed Assets [Line Items]
Laboratory equipment	$4,134	$3,932
Furniture and office equipment	944	815
Software and computers	3,071	2,958
Leasehold improvements	4,554	4,510	4,500
Total	12,703	12,215
Less: accumulated depreciation and amortization	-8,072	-7,255
Property, plant and equipment, Net	$4,631	$4,960

Components_of_Accounts_Payable

Components of Accounts Payable and Accrued Expenses (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Accounts Payable and Accrued Liabilities [Line Items]
Accounts payable	$999	$1,407
Accrued employee compensation and related taxes.	5,759	4,609
Accrued license fees	3,165	348
Accrued legal	262	456
Accounts payable and accrued expenses	17,373	12,542
Research and Development Operations
Accounts Payable and Accrued Liabilities [Line Items]
Accounts payable	3,020	1,778
Sales Allowances
Accounts Payable and Accrued Liabilities [Line Items]
Accounts payable	2,368	1,918
Other Accrued Liabilities
Accounts Payable and Accrued Liabilities [Line Items]
Accounts payable	$1,800	$2,026

LongTerm_Obligations_Additiona

Long-Term Obligations - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	Dec. 31, 2014	Dec. 31, 2013	sqft	Dec. 31, 2011
Debt Disclosure [Line Items]
Principal amount of Loan	$527,000	$580,000
Proceed from unsecured loan			671,000
Decrease in note payable	198,000	198,000
Fair value of note payable	83,000,000
Lease agreement term			10 years
Rentable square feet of office and laboratory facilities			45,000
Aggregate minimum lease commitment over payment lease term	12,123,000		15,000,000
Letter of Credit given to landlord to secure lease obligation			1,100,000
Capitalized leasehold improvements	4,554,000	4,510,000	4,500,000
Operating Leases
Debt Disclosure [Line Items]
Operating Leases, Rent Expense	1,500,000	1,500,000	1,600,000
Maximum
Debt Disclosure [Line Items]
Tenant improvement allowance			2,600,000
Tranche A and Tranche B Loans (Original Loan) \| Warrant
Debt Disclosure [Line Items]
Decrease in note payable	1,300,000
Extended Term
Debt Disclosure [Line Items]
Lease agreement term			5 years
Healthcare Royalty Partners
Debt Disclosure [Line Items]
Loan principal balance	84,500,000	84,500,000
Class of Warrant or Right, Outstanding	500,000
Healthcare Royalty Partners \| Legal Fee
Debt Disclosure [Line Items]
Decrease in note payable	580,000
Healthcare Royalty Partners \| Tranche A and Tranche B Loans (Original Loan)
Debt Disclosure [Line Items]
Debt instrument maturity date	30-Sep-16
Percentage of required payment for partial repayment of debt	90.00%
Healthcare Royalty Partners \| Tranche A and Tranche B Loans (Original Loan) \| Phase 3 Trials
Debt Disclosure [Line Items]
Percentage of required payment for partial repayment of debt	75.00%
Annual net LFRP receipts amount used as a basis for repayment of loan	15,000,000
Healthcare Royalty Partners \| Tranche A and Tranche B Loans (Original Loan) \| Group Two
Debt Disclosure [Line Items]
Percentage of required payment for partial repayment of debt	25.00%
Healthcare Royalty Partners \| Tranche A and Tranche B Loans (Original Loan) \| Group Two \| Minimum
Debt Disclosure [Line Items]
Annual net LFRP receipts amount used as a basis for repayment of loan	15,000,000
Healthcare Royalty Partners \| Tranche A Loan
Debt Disclosure [Line Items]
Principal amount of Loan	21,700,000
Healthcare Royalty Partners \| Tranche B Loan
Debt Disclosure [Line Items]
Principal amount of Loan	58,800,000
Stock Issued During Period, Shares, Conversion of Convertible Securities	233,438
Healthcare Royalty Partners \| Tranche B Loan \| Loan One
Debt Disclosure [Line Items]
Class of Warrant or Right, Outstanding	250,000
Class of Warrant or Right, Exercise Price of Warrants or Rights	$5.50
Warrants and Rights Outstanding	853,000
Fair Value Assumptions, Expected Volatility Rate	83.64%
Fair Value Assumptions, Risk Free Interest Rate	4.07%
Fair Value Assumptions, Expected Term	8 years
Fair Value Assumptions, Expected Dividend Rate	0.00%
Healthcare Royalty Partners \| Tranche B Loan \| Loan Two
Debt Disclosure [Line Items]
Class of Warrant or Right, Outstanding	250,000
Class of Warrant or Right, Exercise Price of Warrants or Rights	$2.87
Warrants and Rights Outstanding	477,000
Fair Value Assumptions, Expected Volatility Rate	85.98%
Fair Value Assumptions, Risk Free Interest Rate	2.77%
Fair Value Assumptions, Expected Term	7 years 4 months 24 days
Fair Value Assumptions, Expected Dividend Rate	0.00%
Healthcare Royalty Partners \| Refinanced Term Loan \| Tranche A Loan \| Legal Fee
Debt Disclosure [Line Items]
Decrease in note payable	193,000
Healthcare Royalty Partners \| Refinanced Term Loan \| Tranche A Loan \| Second Affiliated
Debt Disclosure [Line Items]
Proceed from unsecured loan				20,000,000
Effective interest rate	12.50%	12.60%	13.00%
Healthcare Royalty Partners \| Refinanced Term Loan \| Tranche B Loan \| Second Affiliated
Debt Disclosure [Line Items]
Proceed from unsecured loan			57,600,000
Healthcare Royalty Partners \| LFRP \| Tranche A and Tranche B Loans (Original Loan)
Debt Disclosure [Line Items]
Debt Instrument, Maturity, Month and Year	Aug-18
Interest on lease	12.00%
Healthcare Royalty Partners \| LFRP \| Tranche A Loan
Debt Disclosure [Line Items]
Secured Loan	22,800,000
Healthcare Royalty Partners \| LFRP \| Tranche B Loan
Debt Disclosure [Line Items]
Secured Loan	61,700,000
Silicon Valley Bank \| Equipment lease
Debt Disclosure [Line Items]
Interest on lease			6.00%
Line of credit, maximum borrowing capacity			3,000,000
Line of credit		931,000
Lease agreement term			3 years
Silicon Valley Bank \| Equipment lease \| Negotiable Order of Withdrawal Accounts
Debt Disclosure [Line Items]
Line of credit			$1,400,000

LongTerm_Obligations_and_Note_

Long-Term Obligations and Note Payable (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Note payable	$82,165	$81,516	$78,061
Obligations under equipment loan	0	931
Total	82,165	82,447
Less: current portion	0	-468
Long-term obligations	$82,165	$81,979

Estimated_Future_Payments_Unde

Estimated Future Payments Under Company's Note Payable (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
2015	$10,327
2016	11,812
2017	27,192
2018	70,778
2019 and thereafter	0
Total estimated future payments	120,109
Less: amount representing interest	-35,637
Present value of estimated future payments	84,472
Less: current portion	0	-468
Less: unamortized portion of discount and deferred interest expense	-2,307
Long-term obligations and note payable	$82,165

Activity_under_Loan_Presented_

Activity under Loan Presented for Financial Reporting Purposes (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Beginning balance	$81,516	$78,061
Accretion of discount	198	198
Loan activity:
Interest Expense	10,588	10,447
Payments applied to principal	0	0
Payments applied to interest	-8,978	-5,378
Accrued interest payable	-1,159	-1,812
Ending balance	$82,165	$81,516

Gross_Minimum_Future_Lease_Pay

Gross Minimum Future Lease Payments under Non-Cancelable Operating Leases (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2012
Debt Instrument [Line Items]
2015	$1,613
2016	1,693
2017	1,701
2018	1,764
2019	1,678
Thereafter	3,674
Total	$12,123	$15,000

Restructuring_Charges_Addition

Restructuring Charges - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$0	$0	$1,440,000
Date of completion of restructuring costs			31-Dec-12
Charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges			1,400,000
Severance and Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges			1,200,000
Outplacement Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges			120,000
Stock Compensation Expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges			55,000
Other Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$90,000

Stockholders_Equity_Additional

Stockholders' Equity - Additional Information (Detail) (USD $)	1 Months Ended			12 Months Ended
	Mar. 31, 2014	Oct. 31, 2013	31-May-13	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 28, 2014
Stockholders Equity Note [Line Items]
Common stock, shares issued	9,200,000	10,615,385	8,901,675
Common stock, per share	$9.25	$6.50	$2.30
Proceed from offering	$79,700,000	$64,700,000	$29,100,000
Number of common stock issued upon conversion of preferred stock			41,418				4,141,800
Compensation expense				7,283,000	5,441,000	3,640,000
Share-based Compensation				7,283,000	5,441,000	3,640,000
Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period				2,899,459	3,617,150	5,897,221
Closing Price Per Share				$14.06
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				2 years 5 months 1 day
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$6.16	$2.06	$1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				10,900,000	5,400,000	375,000
Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options				3,800,000	5,100,000	1,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options				19,200,000
Common Shares Issuable On Conversion Of Preferred Stock			100
Preferred Stock Par Or Stated Value Per Share			$230	$0.01	$0.01
Equity Method Investment, Ownership Percentage			9.99%
Employee Stock Purchase Plans
Stockholders Equity Note [Line Items]
Percentage of price per share				85.00%
Employee stock purchase plan offering period				6 months
Contribution of employee in percentage				10.00%
Contribution of employee in shares				875
Compensation expense				176,000	310,000	91,000
Number of shares purchased in period				65,208	94,979	93,974
Number of shares reserved and available for issuance				702,752
1995 Equity Incentive Plan (the Equity Plan)
Stockholders Equity Note [Line Items]
Compensation expense				7,107,000	5,131,000	3,549,000
Number of shares reserved and available for issuance				10,372,949
Stock Compensation Plan
Stockholders Equity Note [Line Items]
Stock based compensation capitalized into inventory				69,000	9,000	23,000
Share-based Compensation				77,000	1,600,000	467,000
Stock Compensation Plan \| Former Executive Officer
Stockholders Equity Note [Line Items]
Share-based Compensation					1,100,000
Stock Options \| 1995 Equity Incentive Plan (the Equity Plan)
Stockholders Equity Note [Line Items]
Vesting period				48 months
Non Vested Restricted Stock
Stockholders Equity Note [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				$2,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				2 years 6 months 11 days

Stock_Compensation_Expense_Det

Stock Compensation Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expenses	$7,283	$5,441	$3,640
Allocation of stock-based compensation expense	0	0	55
Research and Development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocation of stock-based compensation expense	2,788	1,671	839
Selling, General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocation of stock-based compensation expense	4,495	3,770	2,746
Equity Incentive Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expenses	7,107	5,131	3,549
Employee Stock Purchase Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Compensation expenses	$176	$310	$91

Fair_Value_of_Option_Detail

Fair Value of Option (Detail) (Employee Stock Option)	12 Months Ended
Fair Value of Option (Detail) (Employee Stock Option)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate, minimum	1.90%	0.99%	0.86%
Risk-free interest rate, maximum	2.47%	2.21%	1.37%
Volatility factor, minimum	66.00%	70.00%	70.00%
Volatility factor, maximum	72.00%	73.00%	73.00%
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected Option Term (in years)	6 years	6 years	6 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected Option Term (in years)	8 years	8 years	8 years

Fair_Value_of_Shares_Issued_un

Fair Value of Shares Issued under Employee Stock Purchase Plan (Detail) (Employee Stock Purchase Plan)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected Option Term (in years)	6 months	6 months	6 months
Risk-free interest rate, minimum	0.04%	0.06%	0.09%
Risk-free interest rate, maximum	0.07%	0.10%	0.12%
Expected dividend yield	0.00%	0.00%	0.00%
Volatility factor, minimum	47.00%	46.00%	45.00%
Volatility factor, maximum	68.00%	81.00%	54.00%

Stock_Options_Activity_Detail

Stock Options Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Options
Beginning balance	10,628,879
Granted/Awarded	2,899,459	3,617,150	5,897,221
Exercised	-1,448,810
Forfeited	-455,046
Expired	-37,403
Ending balance	11,587,079	10,628,879
Exercisable at end of year	7,055,503
Vested and unvested expected to vest at end of year	11,573,431
Weighted Average Exercise Price
Beginning balance	$2.47
Granted at fair market value	$9.61
Exercised	$2.63
Forfeited	$5.05
Expired	$10.98
Ending balance	$4.11	$2.47
Exercisable at end of year	$2.84
Vested and unvested expected to vest at end of year	$4.11
Weighted Average Remaining Contractual Life
Outstanding at end of period	6 years 10 months 6 days	6 years 11 months 26 days
Exercisable at end of period	5 years 9 months 18 days
Vested and unvested expected to vest at end of period	6 years 10 months 2 days
Aggregate Intrinsic Value
Outstanding at end of period	$53,978
Outstanding at end of period	115,324	53,978
Exercisable at end of period	79,179
Vested and unvested expected to vest at end of period	$115,156

Summary_of_Restricted_Stock_Un

Summary of Restricted Stock Unit Activity (Detail) (Restricted Stock Units (RSUs), USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Restricted Stock Units (RSUs)
Number of Shares
Beginning balance	253,124
Granted	368,541
Vested	-101,877
Forfeited	-33,614
Ending balance	486,174	253,124
Vested and unvested expected to vest	419,036
Exercisable	0
Weighted-Avg. Remaining Contractual Life
Unvested, Outstanding	1 year 4 months 10 days	1 year 5 months 23 days
Vested and unvested expected to vest	1 year 2 months 26 days
Exercisable	0 years
Aggregate Intrinsic Value
Unvested at ending of year	$6,836
Vested and unvested expected to vest	5,892
Exercisable	$0

Employee_Savings_and_Retiremen1

Employee Savings and Retirement Plans - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension And Other Postretirement Benefits Disclosure [Line Items]
Employers discretionary matching contributions in percentage	100.00%
Company matching contributions in percentage	50.00%
Eligible pay in percentage for employee contributions	6.00%
Company's matching contributions amount	$441,000	$451,000	$440,000

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Deferred tax asset, exercise of stock options	$1,800,000	$1,800,000
Deferred tax assets valuation allowance	219,778,000	213,934,000	204,260,000
Federal tax net operating loss carryforward	348,100,000	329,200,000
Federal research and experimentation and orphan drug credit carryforward	68,100,000	61,600,000
State and Local Income Tax Expense (Benefit), Continuing Operations	53,500,000	93,800,000
Net Operating Loss related to stock compensation	5,500,000
Maximum
Income Taxes [Line Items]
Open Tax Year	2014
Minimum
Income Taxes [Line Items]
Open Tax Year	2000
Federal Tax
Income Taxes [Line Items]
Federal tax net operating loss carryforward	260,600,000
Federal research and experimentation and orphan drug credit carryforward	56,800,000
Restricted NOLs	67,200,000
Federal tax credits	4,800,000
Stock Option
Income Taxes [Line Items]
Federal tax net operating loss carryforward	16,700,000	8,200,000
Research and Development Credit Carryforwards
Income Taxes [Line Items]
Federal research and experimentation and orphan drug credit carryforward	$8,800,000	$8,300,000

Provision_for_Income_Taxes_for

Provision for Income Taxes for Continuing Operations (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation Of Statutory Federal Tax Rate [Line Items]
Statutory federal income taxes	34.00%	34.00%	34.00%
State income taxes, net of federal benefit	-14.30%	-4.70%	-3.30%
General business credit	36.20%	4.50%	3.80%
Stock compensation, including cancellations	-9.00%	-0.80%	-6.80%
Other	-0.40%	1.60%	-1.70%
Federal true up and expiring NOLs and research credits	2.70%	0.40%	-8.60%
Valuation allowance	-49.20%	-35.00%	-17.40%
Effective income tax rate	0.00%	0.00%	0.00%

Components_of_Deferred_Tax_Ass

Components of Deferred Tax Assets and Liabilities (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Deferred Tax Asset:
Depreciation and amortization	$204	$228	$255
Accrued expenses	398	642	303
Capitalized research and development costs	21,537	23,603	8,192
Other	1,217	1,339	1,394
Stock based compensation	3,241	2,575	2,127
Deferred revenue	2,569	2,928	4,223
Research credit carryforwards	73,893	67,088	63,259
Net operating loss carryforwards	116,719	115,531	124,507
Total gross deferred tax asset	219,778	213,934	204,260
Valuation allowance	-219,778	-213,934	-204,260
Net deferred tax asset	$0	$0	$0

Summary_of_Unaudited_Quarterly

Summary of Unaudited Quarterly and Annual Results of Operations (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information [Line Items]
Revenues	$26,028	$21,993	$19,585	$14,117	$16,859	$13,691	$11,336	$12,040	$81,723	$53,926	$54,650
Income (loss) from operations	344	1,858	-411	-3,026	755	-3,641	-5,850	-8,463	-1,235	-17,199	-18,885
Net loss	($2,290)	($816)	($3,061)	($5,711)	($1,964)	($6,188)	($8,432)	($11,193)	($11,878)	($27,777)	($29,265)
Shares used in computing basic and diluted net loss per share	136,533,907	136,282,842	135,873,613	124,618,519	119,573,601	109,731,276	104,977,247	99,644,227	133,367,963	108,539,613	98,991,056
Basic and diluted net loss per share:	($0.02)	($0.01)	($0.02)	($0.05)	($0.02)	($0.06)	($0.08)	($0.11)	($0.09)	($0.26)	($0.30)