Keryx Biopharmaceuticals (KERX) 10-K 13 Mar 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Mar. 01, 2014	Jun. 28, 2013
Document Type	'10-K	'	'
Amendment Flag	'false	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'FY	'	'
Trading Symbol	'KERX	'	'
Entity Registrant Name	'KERYX BIOPHARMACEUTICALS INC	'	'
Entity Central Index Key	'0001114220	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Filer Category	'Accelerated Filer	'	'
Entity Common Stock, Shares Outstanding	'	90,912,023	'
Entity Public Float	'	'	$597,771,011

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current assets:	'	'
Cash and cash equivalents	$55,696	$14,677
Other current assets	1,232	430
Total current assets	56,928	15,107
Property, plant and equipment, net	349	56
Goodwill	3,208	3,208
Other assets, net	281	198
Total assets	60,766	18,569
Current liabilities:	'	'
Accounts payable and accrued expenses	14,004	7,212
Accrued compensation and related liabilities	1,324	827
Total current liabilities	15,328	8,039
Other liabilities	38	36
Total liabilities	15,366	8,075
Commitments and contingencies (Notes 14 and 15)	'	'
Stockholders' equity:	'	'
Preferred stock, $0.001 par value per share (5,000,000 shares authorized, no shares issued and outstanding)	'	'
Common stock, $0.001 par value per share (130,000,000 and 95,000,000 shares authorized, 82,723,145 and 72,002,949 shares issued, 82,643,197 and 71,923,001 shares outstanding at December 31, 2013 and 2012, respectively)	83	72
Additional paid-in capital	485,014	403,387
Treasury stock, at cost, 79,948 shares at December 31, 2013 and 2012, respectively	-357	-357
Accumulated deficit	-439,340	-392,608
Total stockholders' equity	45,400	10,494
Total liabilities and stockholders' equity	$60,766	$18,569

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Preferred stock, par value	$0.00	$0.00
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	'	'
Preferred stock, shares outstanding	'	'
Common stock, par value	$0.00	$0.00
Common stock, shares authorized	130,000,000	95,000,000
Common stock, shares issued	82,723,145	72,002,949
Common stock, shares outstanding	82,643,197	71,923,001
Treasury stock, shares	79,948	79,948

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue:	'	'	'
License revenue	$7,000	'	$5,000
Total revenue	7,000	'	5,000
Research and development:	'	'	'
Non-cash compensation	2,347	662	803
Other research and development	32,387	19,369	26,209
Total research and development	34,734	20,031	27,012
General and administrative:	'	'	'
Non-cash compensation	3,606	1,505	1,289
Other general and administrative	15,743	5,543	5,448
Total general and administrative	19,349	7,048	6,737
Total operating expenses	54,083	27,079	33,749
Operating loss	-47,083	-27,079	-28,749
Interest and other income, net	351	1,719	380
Loss from continuing operations before income taxes	-46,732	-25,360	-28,369
Income taxes	'	'	'
Loss from continuing operations	-46,732	-25,360	-28,369
Gain from discontinued operations	'	'	246
Loss before extraordinary gain	-46,732	-25,360	-28,123
Extraordinary gain	'	2,639	'
Net loss	($46,732)	($22,721)	($28,123)
Basic and diluted net loss per common share:	'	'	'
Continuing operations	($0.58)	($0.36)	($0.42)
Discontinued operations	'	'	'	[1]
Extraordinary gain	'	$0.04	'
Basic and diluted net loss per common share	($0.58)	($0.32)	($0.42)
Weighted average shares used in computing basic and diluted net loss per common share	81,009,561	71,633,464	67,370,354
[1]	Amount less than one cent per share.

Consolidated_Statements_of_Sto

Consolidated Statements of Stockholders' Equity (USD $)	Total		Common stock		Additional paid-in capital	Treasury stock	Accumulated deficit
In Thousands, except Share data
Beginning Balance at Dec. 31, 2010	$23,248		$62		$365,307	($357)	($341,764)
Beginning Balance (in shares) at Dec. 31, 2010	'		61,521,483		'	79,948	'
Issuance of common stock in public offering (net of offering costs of $5,640 in 2013 and $2,266 in 2011) (in shares)	'		7,021,277		'	'	'
Issuance of common stock in public offering (net of offering costs of $5,640 in 2013 and $2,266 in 2011)	30,734		7		30,727	'	'
Issuance of restricted stock (in Shares)	'		206,450		'	'	'
Issuance of restricted stock	'	[1]	'	[1]	'	'	'
Forfeiture of restricted stock (in shares)	'		-28,338		'	'	'
Forfeiture of restricted stock	'	[1]	'	[1]	'	'	'
Issuance of common stock in connection with the exercise of options (in shares)	'		2,382,027		'	'	'
Issuance of common stock in connection with the exercise of options	3,096		2		3,094	'	'
Compensation in respect of options and restricted stock granted to employees, directors and third-parties	2,092		'		2,092	'	'
Net loss	-28,123		'		'	'	-28,123
Ending Balance at Dec. 31, 2011	31,047		71		401,220	-357	-369,887
Ending Balance (in shares) at Dec. 31, 2011	'		71,102,899		'	79,948	'
Issuance of restricted stock (in Shares)	'		997,300		'	'	'
Issuance of restricted stock	1		1		'	'	'
Forfeiture of restricted stock (in shares)	'		-97,250		'	'	'
Forfeiture of restricted stock	'	[1]	'	[1]	'	'	'
Compensation in respect of options and restricted stock granted to employees, directors and third-parties	2,167		'		2,167	'	'
Net loss	-22,721		'		'	'	-22,721
Ending Balance at Dec. 31, 2012	10,494		72		403,387	-357	-392,608
Ending Balance (in shares) at Dec. 31, 2012	'		72,002,949		'	79,948	'
Issuance of common stock in public offering (net of offering costs of $5,640 in 2013 and $2,266 in 2011) (in shares)	'		9,469,100		'	'	'
Issuance of common stock in public offering (net of offering costs of $5,640 in 2013 and $2,266 in 2011)	74,753		10		74,743	'	'
Issuance of restricted stock (in Shares)	'		831,020		'	'	'
Issuance of restricted stock	1		1		'	'	'
Forfeiture of restricted stock (in shares)	'		-23,737		'	'	'
Forfeiture of restricted stock	'	[1]	'	[1]	'	'	'
Issuance of common stock in connection with the exercise of options (in shares)	'		443,813		'	'	'
Issuance of common stock in connection with the exercise of options	931		'	[1]	931	'	'
Compensation in respect of options and restricted stock granted to employees, directors and third-parties	5,953		'		5,953	'	'
Net loss	-46,732		'		'	'	-46,732
Ending Balance at Dec. 31, 2013	$45,400		$83		$485,014	($357)	($439,340)
Ending Balance (in shares) at Dec. 31, 2013	'		82,723,145		'	79,948	'
[1]	Amount less than one thousand dollars.

Consolidated_Statements_of_Sto1

Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $)	1 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	4-May-11	Dec. 31, 2013	Dec. 31, 2011
Issuance of common stock in public offering, offering costs	$2,300	$5,640	$2,266

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES	'	'	'
Net loss	($46,732)	($22,721)	($28,123)
Gain from discontinued operations	'	'	246
Extraordinary gain	'	2,639	'
Loss from continuing operations	-46,732	-25,360	-28,369
Adjustments to reconcile loss from continuing operations to cash flows used in operating activities of continuing operations:	'	'	'
Stock compensation expense	5,953	2,167	2,092
Depreciation and amortization	54	35	47
Changes in assets and liabilities, net of effects of acquisitions:	'	'	'
(Increase) decrease in other current assets	-802	104	-334
Decrease (increase) in accrued interest receivable	'	7	-7
Increase in security deposits	'	'	-51
(Increase) decrease in other assets	-83	11	-21
Increase (decrease) in accounts payable and accrued expenses	6,792	-1,658	3,592
Increase (decrease) in accrued compensation and related liabilities	497	-70	228
Increase in other liabilities	2	1	'
Net cash used in operating activities of continuing operations	-34,319	-24,763	-22,823
Net cash provided by operating activities of discontinued operations	'	'	1
Net cash used in operating activities	-34,319	-24,763	-22,822
CASH FLOWS FROM INVESTING ACTIVITIES	'	'	'
Purchases of property, plant and equipment	-346	-24	-57
Investment in held-to-maturity short-term securities	-24,403	-11,263	-9,941
Proceeds from maturity of held-to-maturity short-term securities	24,403	15,475	5,830
Net cash (used in) provided by investing activities	-346	4,188	-4,168
CASH FLOWS FROM FINANCING ACTIVITIES	'	'	'
Proceeds from public offerings, net	74,753	'	30,734
Proceeds from exercise of options	931	'	3,096
Net cash provided by financing activities	75,684	'	33,830
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	41,019	-20,575	6,840
Cash and cash equivalents at beginning of year	14,677	35,252	28,412
CASH AND CASH EQUIVALENTS AT END OF YEAR	$55,696	$14,677	$35,252

Organization_and_Summary_of_Si

Organization and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Organization and Summary of Significant Accounting Policies	'
	NOTE 1 - ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	DESCRIPTION OF BUSINESS
	We are a biopharmaceutical company focused on the acquisition, development and commercialization of pharmaceutical products for the treatment of renal disease. Currently, our only drug candidate is ZerenexTM (ferric citrate coordination complex), an oral, ferric iron-based compound. Our New Drug Application (“NDA”), for the treatment of hyperphosphatemia (elevated phosphate levels) in patients with chronic kidney disease (“CKD”) on dialysis, is currently under review by the Food and Drug Administration (“FDA”) with an assigned Prescription Drug User Fee Act (“PDUFA”) goal date of June 7, 2014. In addition, in March 2014, we submitted a Marketing Authorization Application (“MAA”) with the European Medicines Agency (“EMA”) seeking the approval of Zenerex as a treatment for hyperphosphatemia in patients with CKD, including dialysis and non-dialysis dependent CKD.
	We own a 100% interest in each of ACCESS Oncology, Inc. (“ACCESS Oncology”), Neryx Biopharmaceuticals, Inc., and Accumin Diagnostics, Inc. (“ADI”), all inactive U.S. corporations incorporated in the State of Delaware. Most of our biopharmaceutical development and substantially all of our administrative operations during 2013, 2012 and 2011 were conducted in the U.S.
	LIQUIDITY AND CAPITAL RESOURCES
	Except for 2009, we have incurred substantial operating losses since our inception, and expect to continue to incur operating losses for the foreseeable future and may never become profitable. As of December 31, 2013, we have an accumulated deficit of $439.3 million.
	Our major sources of cash have been proceeds from various public and private offerings of our common stock, option and warrant exercises, interest income, and from the upfront and milestone payments from our Sublicense Agreement with Japan Tobacco Inc. (“JT”) and Torii Pharmaceutical Co., Ltd. (“Torii”) and miscellaneous payments from our other prior licensing activities. We have not yet commercialized any drug candidate and cannot be sure if we will ever be able to do so. Even if we commercialize a drug candidate, we may not become profitable. Our ability to achieve profitability depends on a number of factors, including our ability to complete our development efforts, obtain regulatory approval for our drug candidate, successfully complete any post-approval regulatory obligations and successfully manufacture and commercialize our drug candidate alone or in partnership. We may continue to incur substantial operating losses even if we begin to generate revenues from our drug candidate, if approved.
	In January 2013, we raised approximately $74.8 million, net of underwriting discounts and offering expenses of approximately $5.6 million, in an underwritten public offering. In January 2014, we raised approximately $107.6 million, net of underwriting discounts and offering expenses of approximately $7.5 million, in an underwritten public offering. We have a shelf registration statement on Form S-3 filed and declared effective by the Securities and Exchange Commission in August 2013, which provides for the offering of up to $150 million of common stock and warrants in the aggregate. Subsequent to the underwritten public offerings that were completed in January 2013 and January 2014, there remains approximately $34.9 million of our common stock and warrants available for sale on this shelf registration statement.
	We currently expect that our existing capital resources combined with future anticipated cash flows will be sufficient to operate our business plan. The actual amount of cash that we will need to operate is subject to many factors, including, but not limited to, the timing and expenditures associated with the build-up of prelaunch/launch inventory and capacity expansion, the timing and expenditures associated with the respective regulatory review processes for our U.S. NDA and EU MAA filings, the timing and expenditures associated with pre-commercial/commercial activities related to Zerenex, and the timing, design and conduct of clinical trials for Zerenex. We may depend upon significant additional financings to provide the cash necessary to execute our current operations, including the commercialization of Zerenex.
	Our common stock is listed on the NASDAQ Capital Market and trades under the symbol “KERX.”
	CORPORATE
	In September 2013, the Board of Directors increased the total number of board members to seven and appointed Daniel P. Regan as a director to fill the newly-created position.
	In February 2014, Greg Madison was appointed as Executive Vice President and Chief Operating Officer.
	RECENTLY ISSUED ACCOUNTING STANDARDS
	None.
	PRINCIPLES OF CONSOLIDATION
	The consolidated financial statements include our financial statements and those of our wholly-owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation.
	USE OF ESTIMATES
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the applicable reporting period. Actual results could differ from those estimates. Such differences could be material to the financial statements.
	CASH AND CASH EQUIVALENTS
	We treat liquid investments with original maturities of three months or less when purchased as cash and cash equivalents.
	INVESTMENT SECURITIES
	We were not invested in investment securities at December 31, 2013 and 2012, respectively.
	PROPERTY, PLANT AND EQUIPMENT
	Property, plant and equipment are stated at historical cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets:
		Estimated
		useful life
		(years)
	Office furniture and equipment	7-Mar
	Computers, software and related equipment	3
	Leasehold improvements are amortized over the shorter of their useful life or the remaining term of the lease exclusive of renewal options.
	PATENT COSTS
	We expense patent maintenance costs as incurred. We have classified our patent expenses in other general and administrative.
	REVENUE RECOGNITION
	We recognize license revenue in accordance with the revenue recognition guidance of the FASB Accounting Standards Codification (the “Codification”). We analyze each element of our licensing agreement to determine the appropriate revenue recognition. The terms of the license agreement may include payments to us of non-refundable up-front license fees, milestone payments if specified objectives are achieved, and/or royalties on product sales. We recognize revenue from upfront payments over the period of significant involvement under the related agreements unless the fee is in exchange for products delivered or services rendered that represent the culmination of a separate earnings process and no further performance obligation exists under the contract. We recognize milestone payments as revenue upon the achievement of specified milestones only if (1) the milestone payment is non-refundable, (2) substantive effort is involved in achieving the milestone, (3) the amount of the milestone is reasonable in relation to the effort expended or the risk associated with achievement of the milestone, and (4) the milestone is at risk for both parties. If any of these conditions are not met, we defer the milestone payment and recognize it as revenue over the estimated period of performance under the contract (see Note 9 – License Agreements).
	Other revenue consists of fees and payments arising from technology transfer, termination and settlement agreements related to our prior license agreements. Other revenues are recognized at the time such fees and payments are earned.
	RESEARCH AND DEVELOPMENT COSTS
	Research and development costs are expensed as incurred. Pre-approval inventory expenditures are recorded as research and development expense as incurred. The capitalization of inventory for our product candidate will commence when it is probable that our product will be approved for commercial marketing. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and amortized over the period that the goods are delivered or the related services are performed, subject to an assessment of recoverability. We make estimates of costs incurred in relation to external clinical research organizations (“CROs”) and clinical site costs. We analyze the progress of clinical trials, including levels of patient enrollment, invoices received and contracted costs when evaluating the adequacy of the amount expensed and the related prepaid asset and accrued liability. Significant judgments and estimates must be made and used in determining the accrued balance and expense in any accounting period. We review and accrue CRO expenses and clinical trial study expenses based on work performed and rely upon estimates of those costs applicable to the stage of completion of a study. Accrued CRO costs are subject to revisions as such trials progress to completion. Revisions are charged to expense in the period in which the facts that give rise to the revision become known. With respect to clinical site costs, the financial terms of these agreements are subject to negotiation and vary from contract to contract. Payments under these contracts may be uneven, and depend on factors such as the achievement of certain events, the successful recruitment of patients, the completion of portions of the clinical trial or similar conditions. The objective of our policy is to match the recording of expenses in our financial statements to the actual services received and efforts expended. As such, expense accruals related to clinical site costs are recognized based on our estimate of the degree of completion of the event or events specified in the specific clinical study or trial contract.
	INCOME TAXES
	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, operating losses and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. If the likelihood of realizing the deferred tax assets or liability is less than “more likely than not,” a valuation allowance is then created.
	We, and our subsidiaries, file income tax returns in the U.S. federal jurisdiction and in various states. We have tax net operating loss carryforwards that are subject to examination for a number of years beyond the year in which they were generated for tax purposes. Since a portion of these net operating loss carryforwards may be utilized in the future, many of these net operating loss carryforwards will remain subject to examination.
	We are continuing our practice of recognizing interest and penalties related to uncertain income tax positions in income tax expense.
	STOCK - BASED COMPENSATION
	We recognize all share-based payments to employees and to non-employee directors for service on our board of directors as compensation expense in the consolidated financial statements based on the grant date fair values of such payments. Stock-based compensation expense recognized each period is based on the value of the portion of share-based payment awards that is ultimately expected to vest during the period. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.
	For share-based payments to consultants and other third-parties, compensation expense is determined at the “measurement date.” The expense is recognized over the vesting period of the award. Until the measurement date is reached, the total amount of compensation expense remains uncertain. We record compensation expense based on the fair value of the award at the reporting date. The awards to consultants and other third-parties are then revalued, or the total compensation is recalculated based on the then current fair value, at each subsequent reporting date.
	BASIC AND DILUTED NET LOSS PER COMMON SHARE
	Basic net loss per share is computed by dividing the losses allocable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss per share does not reflect the effect of shares of common stock to be issued upon the exercise of stock options and warrants, as their inclusion would be anti-dilutive. The options outstanding as of December 31, 2013, 2012 and 2011, which are not included in the computation of net loss per share amounts, were 3,845,370, 3,401,671 and 3,517,000, respectively. No warrants were outstanding during each of these periods.
	SEGMENT REPORTING
	Following the discontinuation of the Services segment in December 2011, we have determined that we operate in only one reportable segment: the Products segment.
	ACQUISITIONS
	We adopted ASC Topic 805, Business Combinations, as of January 1, 2009. The adoption of ASC Topic 805 was effective on a prospective basis. Prior to the adoption of ASC Topic 805, we accounted for acquired businesses using the purchase method of accounting which required that the assets acquired and liabilities assumed be recorded at the date of acquisition at their respective fair values. Our consolidated financial statements and results of operations through 2008 reflected an acquired business after the completion of the acquisition and were not retroactively restated. The cost to acquire a business, including transaction costs, was allocated to the underlying net assets of the acquired business in proportion to their respective fair values. Any excess of the purchase price over the estimated fair values of the net assets acquired was recorded as goodwill. Any excess of the net assets acquired over the purchase price represented negative goodwill.
	IMPAIRMENT
	Long lived assets are reviewed for an impairment loss when circumstances indicate that the carrying value of long-lived tangible and intangible assets with finite lives may not be recoverable. Management’s policy in determining whether an impairment indicator exists, a triggering event, comprises measurable operating performance criteria as well as qualitative measures. If an analysis is necessitated by the occurrence of a triggering event, we make certain assumptions in determining the impairment amount. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future cash flows expected to be generated by the asset or used in its disposal. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized.
	Goodwill is reviewed for impairment annually, or when events arise that could indicate that an impairment exists. We test for goodwill impairment using a two-step process. The first step compares the fair value of the reporting unit with the unit’s carrying value, including goodwill. When the carrying value of the reporting unit is greater than fair value, the unit’s goodwill may be impaired, and the second step must be completed to measure the amount of the goodwill impairment charge, if any. In the second step, the implied fair value of the reporting unit’s goodwill is compared with the carrying amount of the unit’s goodwill. If the carrying amount is greater than the implied fair value, the carrying value of the goodwill must be written down to its implied fair value. As of December 31, 2011, 2012 and 2013, management conducted its annual assessments of goodwill and concluded that there were no impairments. We will continue to perform impairment tests annually, at December 31, and whenever events or changes in circumstances suggest that the carrying value of an asset may not be recoverable.
	CONCENTRATIONS OF CREDIT RISK
	We do not have significant off-balance-sheet risk or credit risk concentrations. We maintain our cash and cash equivalents and held-to-maturity investments, when applicable, with multiple financial institutions that invest in investment-grade securities with average maturities of less than twelve months. See Note 3 – Investment Securities and Note 4 – Fair Value Measurements.

Cash_and_Cash_Equivalents

Cash and Cash Equivalents	12 Months Ended
	Dec. 31, 2013
Cash and Cash Equivalents	'
	NOTE 2 - CASH AND CASH EQUIVALENTS
	(in thousands)	31-Dec-13		31-Dec-12
	Money market funds	$	29,904	$	7,137
	Checking and bank deposits		25,792		7,540
	Total	$	55,696	$	14,677
	A significant portion of our cash is maintained in Federal Deposit Insurance Corporation (“FDIC”) insured accounts at credit qualified financial institutions. At times, such amounts may exceed the FDIC insurance limits. At December 31, 2013, uninsured cash balances totaled approximately $55.4 million.

Investment_Securities

Investment Securities	12 Months Ended
	Dec. 31, 2013
Investment Securities	'
	NOTE 3 - INVESTMENT SECURITIES
	We were not invested in investment securities at December 31, 2013 and 2012, respectively.

Fair_Value_Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2013
Fair Value Measurements	'
	NOTE 4 - FAIR VALUE MEASUREMENTS
	We measure certain financial assets and liabilities at fair value on a recurring basis in the financial statements. The hierarchy ranks the quality and reliability of inputs, or assumptions, used in the determination of fair value and requires financial assets and liabilities carried at fair value to be classified and disclosed in one of the following three categories:
		•		Level 1 – quoted prices in active markets for identical assets and liabilities;
		•		Level 2 – inputs other than Level 1 quoted prices that are directly or indirectly observable; and
		•		Level 3 – unobservable inputs that are not corroborated by market data.
	We review investment securities for impairment and to determine the classification of the impairment as temporary or other-than-temporary. Losses are recognized in our consolidated statement of operations when a decline in fair value is determined to be other-than-temporary. We review our investments on an ongoing basis for indications of possible impairment. Once identified, the determination of whether the impairment is temporary or other-than-temporary requires significant judgment.
	The following table provides the fair value measurements of applicable financial assets as of December 31, 2013 and 2012:
			Financial assets at fair value
			as of December 31, 2013
	(in thousands)		Level 1		Level 2		Level 3
	Money market funds (1)		$	29,904	$	—	$	—
	Total		$	29,904	$	—	$	—
			Financial assets at fair value
			as of December 31, 2012
	(in thousands)		Level 1		Level 2		Level 3
	Money market funds (1)		$	7,137	$	—	$	—
	Total		$	7,137	$	—	$	—
	-1	Included in cash and cash equivalents on our consolidated balance sheet. The carrying amount of money market funds is a reasonable estimate of fair value.

Property_Plant_and_Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment	'
	NOTE 5 - PROPERTY, PLANT AND EQUIPMENT
	(in thousands)	31-Dec-13			31-Dec-12
	Leasehold improvements	$	32		$	20
	Office furniture and equipment		556			329
	Computers, software and related equipment		638			530
			1,226			879
	Accumulated depreciation and amortization		(877	)		(823	)
	Net book value	$	349		$	56
	Depreciation expense for the years ended December 31, 2013, 2012 and 2011 was approximately $54,000, $35,000 and $47,000, respectively. The following table summarizes depreciation expense for the years ended December 31, 2013, 2012 and 2011.
		For the year ended December 31
	(in thousands)	2013			2012			2011
	Depreciation expense:
	Research and development		32			21			28
	General and administrative		22			14			19
	Total	$	54		$	35		$	47

Goodwill

Goodwill	12 Months Ended
	Dec. 31, 2013
Goodwill	'
	NOTE 6 - GOODWILL
	On April 6, 2006, ADI, our wholly-owned subsidiary, completed the acquisition of AccuminTM, a novel, patent protected, diagnostic for the direct measurement of total, intact urinary albumin, from AusAm Biotechnologies, Inc. The purchase price of Accumin was $3,996,000. We accounted for the ADI transaction as a purchase. The excess of the purchase price over the net assets acquired in the ADI transaction represented goodwill of approximately $3,208,000, which was allocated to our Products segment based on the proposed synergies with our then existing drug pipeline activities. In September 2008, we terminated our license agreement related to the ADI product.

Other_Assets

Other Assets	12 Months Ended
	Dec. 31, 2013
Other Assets	'
	NOTE 7 - OTHER ASSETS
	(in thousands)	31-Dec-13			31-Dec-12
	Patents and other indefinite-lived intangible assets	$	352		$	352
	Deposits		163			163
	Deferred registration fees		118			35
			633			550
	Accumulated amortization		(352	)		(352	)
		$	281		$	198
	There were no amortization expenses for the years ended December 31, 2013, 2012 and 2011. We do not expect to record amortization expenses going forward, as all intangible assets are fully amortized.

Discontinued_Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2013
Discontinued Operations	'
	NOTE 8 - DISCONTINUED OPERATIONS
	In December 2011, we ceased the operations of Online Collaborative Oncology Group, which was providing clinical trial management and site recruitment services and ceased all operations related to the Services segment. The results of our Services segment and the related financial positions have been reflected as discontinued operations in the consolidated financial statements. The consolidated financial statements have been reclassified to conform to a discontinued operations presentation for all historical periods presented.
	For the year ended December 31, 2011, we recorded a reversal of previously recorded estimated liabilities associated with our discontinued operations of $246,000. Summarized selected financial information for discontinued operations are as follows:
		For the year ended December 31
	(in thousands)	2013		2012		2011
	Service revenue	$	—	$	—	$	156
	Operating expenses:
	Cost of services		—		—		(90	)
	Total operating income		—		—		246
	Gain from discontinued operations	$	—	$	—	$	246

License_Agreements

License Agreements	12 Months Ended
	Dec. 31, 2013
License Agreements	'
	NOTE 9 - LICENSE AGREEMENTS
	In September 2007, we entered into a Sublicense Agreement with JT and Torii, JT’s pharmaceutical business subsidiary, under which JT and Torii obtained the exclusive sublicense rights for the development and commercialization of ferric citrate in Japan, which is being developed in the U.S. under the trade name Zerenex. JT and Torii are responsible for the future development and commercialization costs in Japan. Effective as of June 8, 2009, we entered into an Amended and Restated Sublicense Agreement (the “Revised Agreement”) with JT and Torii, which, among other things, provided for the elimination of all significant on-going obligations under the sublicense agreement.
	In April 2011, JT and Torii commenced a Phase 3 clinical program of ferric citrate in Japan. Under the terms of the license agreement with JT and Torii, we received a non-refundable milestone payment of $5.0 million in April 2011 for the achievement of the Phase 3 commencement milestone. As a result, we recorded license revenue of $5.0 million in accordance with our revenue recognition policy, which is included in the year ended December 31, 2011.
	In January 2013, JT and Torii filed its NDA with the Japanese Ministry of Health, Labour and Welfare for marketing approval of ferric citrate in Japan for the treatment of hyperphosphatemia in patients with CKD. Under the terms of the license agreement with JT and Torii, we received a non-refundable milestone payment of $7.0 million in January 2013 for the achievement of the NDA filing milestone. As a result, we recorded license revenue of $7.0 million in accordance with our revenue recognition policy, which is included in the year ended December 31, 2013.
	In January 2014, JT and Torii received manufacturing and marketing approval of ferric citrate from the Japanese Ministry of Health, Labour and Welfare. Ferric citrate, to be marketed in Japan by JT’s subsidiary, Torii Pharmaceutical Co., Ltd., under the brand name Riona®, is indicated as an oral treatment for the improvement of hyperphosphatemia in patients with CKD. Under the terms of the license agreement with JT and Torii, Keryx received a non-refundable payment of $10.0 million in February 2014 for the achievement of the marketing approval milestone. Keryx will also receive double-digit tiered royalties on net sales of Riona® in Japan, as well as up to an additional $55.0 million upon the achievement of certain annual net sales milestones.
	On April 2, 2012, we reported that the Phase 3 “X-PECT” (Xeloda® + Perifosine Evaluation in Colorectal cancer Treatment) clinical trial evaluating perifosine (KRX-0401) + capecitabine (Xeloda) in patients with refractory advanced colorectal cancer did not meet the primary endpoint of improving overall survival versus capecitabine + placebo. On May 4, 2012, we executed a License Termination and Technology Transfer Agreement with Aeterna Zentaris GmbH (“Zentaris”), whereby the license agreement for KRX-0401 (perifosine) was terminated, and in exchange for the transfer of the U.S. Investigational New Drug Application, development data, intellectual property and contracts to Zentaris, we will receive a royalty on future net sales, if any, of perifosine in the U.S., Canada and Mexico. Zentaris has assumed all costs related to the Perifosine program going forward.

Contingent_Equity_Rights

Contingent Equity Rights	12 Months Ended
	Dec. 31, 2013
Contingent Equity Rights	'
	NOTE 10 - CONTINGENT EQUITY RIGHTS
	On February 5, 2004, we acquired ACCESS Oncology, a related party, for a purchase price of approximately $19,502,000. The purchase price included our assumption of certain liabilities of ACCESS Oncology equal to approximately $8,723,000, the issuance of shares of our common stock valued at approximately $6,325,000, contingent equity rights valued at approximately $4,004,000 and transaction costs of approximately $450,000.
	At the effective date of the merger, each share of ACCESS Oncology common stock, including shares issuable upon the exercise of options exercised before March 1, 2004, and upon the exercise of outstanding warrants, was converted into the right to share in the contingent equity rights pro rata with the other holders of ACCESS Oncology common stock. Pursuant to the merger agreement, 623,145 shares of our common stock valued at approximately $6,325,000 have been issued to the former preferred stockholders of ACCESS Oncology. An additional 4,433 shares of our common stock are issuable to those preferred stockholders of ACCESS Oncology who have yet to provide the necessary documentation to receive shares of our common stock.
	On December 16, 2009, we announced the initiation of a Phase 3 registration trial of KRX-0401 (perifosine) for the treatment of patients with relapsed / refractory multiple myeloma. The achievement of this event triggered contingent milestone stock consideration payable to the former stockholders of ACCESS Oncology in the amount of an aggregate of 500,000 shares of our common stock valued at $1,365,000.
	Due to the termination of the license for KRX-0401 in May 2012, we were no longer committed to pay to the former stockholders of ACCESS Oncology, Inc. certain contingent equity rights (up to 2,872,422 shares of our common stock). For the year ended December 31, 2012, we recognized a non-cash extraordinary gain of $2.6 million relating to the write-off of the contingent equity rights liability.

Stockholders_Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2013
Stockholders' Equity	'
	NOTE 11 - STOCKHOLDERS’ EQUITY
	Preferred Stock
	Our amended and restated certificate of incorporation authorizes the issuance of up to 5,000,000 shares of preferred stock, $0.001 par value, with rights senior to those of our common stock.
	Common Stock
	On June 18, 2013, at the 2013 Annual Meeting of Stockholders, the Company’s stockholders approved an amendment to the Company’s amended and restated certificate of incorporation increasing the shares of authorized common stock from 95,000,000 shares to 130,000,000 shares $0.001 par value common stock. The number of authorized shares of preferred stock remains unchanged at 5,000,000 shares.
	On January 22, 2014, we announced the pricing of an underwritten public offering, whereby we sold 7,935,000 shares of our common stock at a price of $14.50 per share for gross proceeds of approximately $115.1 million. Net proceeds from this offering were approximately $107.6 million, net of underwriting discounts and offering expenses of approximately $7.5 million. The shares were sold under a Registration Statement (No. 333-190353) on Form S-3, filed by us with the Securities and Exchange Commission. This shelf registration statement on Form S-3, filed and declared effective by the SEC in August 2013, provides for the offering of up to $150 million of common stock and warrants in the aggregate. Subsequent to this underwritten public offering, there remains approximately $34.9 million of our common stock and warrants available for sale on this shelf registration statement. We may offer the securities under our shelf registration statement from time to time in response to market conditions or other circumstances if we believe such a plan of financing is in our best interests and the best interests of our stockholders.
	On January 30, 2013, we announced the pricing of an underwritten public offering, whereby we sold 9,469,100 shares of our common stock at a price of $8.49 per share for gross proceeds of approximately $80.4 million. Net proceeds from this offering were approximately $74.8 million, net of underwriting discounts and offering expenses of approximately $5.6 million. The shares were sold under Registration Statements (Nos. 333-171517 and 333-186332) on Form S-3 and Form S-3MEF, respectively, and filed by us with the Securities and Exchange Commission.
	On May 4, 2011, we announced the pricing of an underwritten registered offering of 7,021,277 shares of our common stock at a price of $4.70 per share for gross proceeds of approximately $33.0 million. Net proceeds from this offering were approximately $30.7 million, net of underwriting discounts and offering expenses of approximately $2.3 million. The shares were sold under a shelf registration statement on Form S-3 (File No. 333-171517) that was previously filed and declared effective by the SEC on January 28, 2011.
	Treasury Stock
	As of December 31, 2013 and 2012, we held a total of 79,948 shares of our common stock in treasury, at a total cost of $357,000.
	Equity Incentive Plans
	We have in effect the following stock option and incentive plans.
	a. The 1999 Stock Option Plan was adopted in November 1999. Under the 1999 Stock Option Plan, our board of directors could grant stock-based awards to directors, consultants and employees. The plan authorizes grants to purchase up to 4,230,000 shares of authorized but unissued common stock. The plan limits the term of each option, to no more than 25 years from the date of the grant, unless otherwise authorized by the board. The plan permits the board of directors or a committee appointed by the board to administer the plan. The administrator has the authority, in its discretion, to determine the terms and conditions of any option granted to a service provider, including the vesting schedule. As of December 31, 2013, no additional shares of our common stock may be issued under the 1999 Stock Option Plan.
	b. The 2004 Long-Term Incentive Plan was adopted in June 2004 by our stockholders. Under the 2004 Long-Term Incentive Plan, the compensation committee of our board of directors is authorized to grant stock-based awards to directors, consultants and employees. The 2004 plan authorizes grants to purchase up to 4,000,000 shares of authorized but unissued common stock. The plan limits the term of each option to no more than 10 years from the date of grant. As of December 31, 2013, up to an additional 244,165 shares may be issued under the 2004 Long-Term Incentive Plan.
	c. The 2007 Incentive Plan was adopted in June 2007 by our stockholders. Under the 2007 Incentive Plan, the compensation committee of our board of directors is authorized to grant stock-based awards to directors, consultants, employees and officers. The 2007 Incentive Plan authorizes grants to purchase up to 6,000,000 shares of authorized but unissued common stock. The plan limits the term of each option to no more than 10 years from the date of grant. As of December 31, 2013, up to an additional 9,837 shares may be issued under the 2007 Incentive Plan.
	d. The 2009 CEO Incentive Plan was adopted in May 2009. Under the 2009 CEO Incentive Plan, our board of directors granted an option to Ron Bentsur, our Chief Executive Officer, to purchase up to 600,000 shares of authorized but unissued common stock. The option has a term of 10 years from the date of grant. As of December 31, 2013, the option is fully vested and exercisable.
	e. The 2013 Incentive Plan was adopted in June 2013 by our stockholders at our 2013 Annual Meeting of Stockholders. Under the 2013 Incentive Plan, the compensation committee of the Company’s board of directors is authorized to grant stock-based awards to directors, officers, employees and consultants. The 2013 Incentive Plan authorizes grants to purchase up to 3,500,000 shares of authorized but unissued common stock. The plan limits the term of each option to no more than 10 years from the date of their grant. As of December 31, 2013, up to an additional 2,871,000 shares may be issued under the 2013 Incentive Plan.
	Total shares available for the issuance of stock options or other stock-based awards under our stock option and incentive plans were 3,125,002 shares at December 31, 2013.
	Stock Options
	The following table summarizes stock option activity for all plans for the years ended December 31, 2013, 2012 and 2011:
		Number			Weighted-		Weighted-		Aggregate
		of shares			average		average		Intrinsic
					exercise		Contractual		Value
					price		Term
	Outstanding at January 1, 2011		7,638,403		$	7.05
	Granted		692,350			4.53
	Exercised		(2,382,027	)		1.3			$	6,604,300
	Forfeited		(98,600	)		4.32
	Expired		(2,333,126	)		13.26
	Outstanding at December 31, 2011		3,517,000			6.4			$	2,139,130
	Granted		521,500			2.36
	Exercised		—			—			$	—
	Forfeited		(266,621	)		7.77
	Expired		(370,208	)		11.02
	Outstanding at December 31, 2012		3,401,671			5.17			$	2,373,509
	Granted		932,366			6.29
	Exercised		(443,813	)		2.1			$	4,614,741
	Forfeited		(44,854	)		8.7
	Expired		—			—
	Outstanding at December 31, 2013		3,845,370		$	5.75		6.2	$	28,361,438
	Vested and expected to vest at December 31, 2013		3,804,543		$	5.76		6.2	$	28,045,772
	Exercisable at December 31, 2013		2,519,162		$	5.74		5	$	18,719,371
	The following table summarizes information about stock options outstanding at December 31, 2013:
		Options outstanding							Options exercisable
	Range of exercise prices	Number			Weighted-		Weighted-		Number		Weighted-
		outstanding			average		average		exercisable		average
					remaining		exercise				exercise
					contractual		price				price
					life (years)
	$ 0.10 - $ 3.00		1,698,612			7	$	1.64		1,078,621	$	1.11
	3.70 - 8.56		1,106,208			7.5		5.74		656,991		4.94
	9.34 - 14.64		1,040,550			3.5		12.48		783,550		12.78
	$ 0.10 - $ 14.64		3,845,370			6.2	$	5.75		2,519,162	$	5.74
	Upon the exercise of stock options, we issue new shares of our common stock. As of December 31, 2013, 77,500 options issued to employees and 50,000 options issued to consultants are unvested, milestone-based options.
	Restricted Stock
	Certain employees, directors and consultants have been awarded restricted stock under the 2004 Long-Term Incentive Plan and 2007 Incentive Plan. The time-vesting restricted stock grants vest primarily over a period of three to four years. The following table summarizes restricted share activity for the years ended December 31, 2013, 2012 and 2011:
		Number			Weighted		Aggregate
		of Shares			Average		Intrinsic
					Grant		Value
					Date Fair
					Value
	Outstanding at January 1, 2011		1,400,694		$	1.63	$	6,415,179
	Granted		206,450			4.49
Vested		(957,225	)		1.2	$	4,650,171
Forfeited		(28,338	)		3.35
Outstanding at December 31, 2011		621,581			3.16	$	1,572,600
Granted		997,300			1.94
Vested		(339,954	)		2.91	$	965,496
Forfeited		(97,250	)		2.33
Outstanding at December 31, 2012		1,181,677			2.27	$	3,095,994
Granted		831,020			7.68
Vested		(568,030	)		2.43	$	4,612,275
Forfeited		(23,737	)		8.52
Outstanding at December 31, 2013		1,420,930		$	5.27	$	18,401,044
As of December 31, 2013, 390,000 and 100,000 shares of restricted stock issued to employees and consultants, respectively, are unvested, milestone-based shares.
On September 14, 2009, we entered in an employment agreement with Ron Bentsur, our Chief Executive Officer, which was amended on January 13, 2012, and further amended on June 11, 2013. The agreement, as amended, terminates on May 20, 2015, subject to certain early termination events. As of December 31, 2013, Mr. Bentsur has been granted a total of 750,000 shares of restricted stock based on the achievement of certain milestone awards described in his employment agreement. In addition, as of December 31, 2013, Mr. Bentsur has the opportunity to earn certain milestone awards as follows:
(1) 500,000 shares of fully vested common stock will be granted to Mr. Bentsur, upon the first to occur of (a) our first commercial sale of Zerenex in the U.S. off an approved NDA, (b) our receipt of the first royalty upon the commercial sale of Zerenex in the U.S. by a partner to whom we have sold exclusive or non-exclusive commercial rights, or (c) our complete outlicensing of the entire product rights of Zerenex in the U.S.
(2) 100,000 shares of restricted stock will be granted to Mr. Bentsur upon each event of our outlicensing Zerenex in a foreign market, other than Japan, resulting in a greater than $10 million non-refundable cash payment to us with a gross deal value to us of at least $50 million. Such restricted stock will vest in equal installments over each of the first three anniversaries of the date of grant, provided that Mr. Bentsur remains an employee during such vesting period.
Stock-Based Compensation
The fair value of stock options granted is estimated at the date of grant using the Black-Scholes pricing model. The expected term of options granted is derived from historical data and the expected vesting period. Expected volatility is based on the historical volatility of our common stock. The risk-free interest rate is based on the U.S. Treasury yield for a period consistent with the expected term of the option in effect at the time of the grant. We have assumed no expected dividend yield, as dividends have never been paid to stock or option holders and will not be paid for the foreseeable future.
Black-Scholes Option Valuation Assumptions	2013		2012	2011
Risk-free interest rates	0.70%		0.60%	1.40%
Dividend yield	—		—	—
Volatility	102.00%		106.30%	115.00%
Weighted-average expected term	3.8 years		4.0 years	4.0 years
The weighted average grant date fair value of options granted was $4.28, $1.73 and $3.43 per option for the years ended December 31, 2013, 2012 and 2011, respectively. We used historical information to estimate forfeitures within the valuation model. As of December 31, 2013, there was $3.3 million and $5.7 million of total unrecognized compensation cost related to non-vested stock options and restricted stock, respectively, which is expected to be recognized over weighted-average periods of 2.2 years and 2.6 years, respectively. These amounts do not include, as of December 31, 2013, 127,500 options outstanding and 490,000 shares of restricted stock outstanding which are milestone-based and vest upon certain corporate milestones, such as FDA approval of our drug candidate and change in control. Stock-based compensation will be measured and recorded if and when it is probable that the milestone will occur.
The following table summarizes stock-based compensation expense information about stock options and restricted stock for the years ended December 31, 2013, 2012 and 2011:
	For the year ended December 31,
(in thousands)	2013			2012		2011
Stock-based compensation expense associated with restricted stock	$	3,859		$	967	$	1,044
Stock-based compensation expense associated with option grants		2,094			1,200		1,048
	$	5,953		$	2,167	$	2,092

Income_Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2013
Income Taxes	'
	NOTE 12 - INCOME TAXES
	We account for income taxes under the asset and liability method. Deferred tax assets and liabilities are determined based on differences between the financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. A valuation allowance is established when necessary to reduce deferred tax assets to the amount expected to be realized. In determining the need for a valuation allowance, management reviews both positive and negative evidence, including current and historical results of operations, future income projections and the overall prospects of our business. Based upon management’s assessment of all available evidence, we believe that it is more-likely-than-not that the deferred tax assets will not be realizable; and therefore, a full valuation allowance is established. The valuation allowance for deferred tax assets was $162.8 million and $143.2 million as of December 31, 2013 and 2012, respectively.
	As of December 31, 2013, we have U.S. net operating loss carryforwards (“NOL’s”) of approximately $401.3 million, of which approximately $58.3 million were derived from certain stock option exercises and any such benefit realized will be credited to additional paid in capital. For income tax purposes, these NOL’s will expire in the years 2019 through 2032. Due to our various equity transactions, the utilization of certain NOL’s could be subject to annual limitations imposed by Internal Revenue Code Section 382 relating to the change of control provision and/or the separate return limitation year losses limitation.
	Income tax expense differed from amounts computed by applying the US federal income tax rate of 34% to pretax loss as follows:
		For the year ended
		December 31,
	(in thousands)	2013			2012			2011
	Loss from continuing operations before income taxes, as reported in the consolidated statements of operations	$	(46,732	)	$	(25,360	)	$	(28,369	)
	Computed “expected” tax (benefit) expense		(15,889	)		(8,622	)		(9,645	)
	Increase (decrease) in income taxes resulting from:
	Expected (benefit) expense from state & local taxes		(1,523	)		(827	)		(925	)
	Stock compensation		(1,842	)		905			5,872
	Deferred impact rate change		—			—			19,072
	Permanent differences		66			(196	)		(147	)
	Other		—			—			(2	)
	Prior year true-up		(409	)		(6,450	)		(829	)
	Change in the balance of the valuation allowance for deferred tax assets allocated to income tax expense		19,597			15,190			(13,396	)
		$	—		$	—		$	—
	The significant components of deferred income tax expense (benefit) attributable to loss from operations are as follows:
		For the year ended
		December 31,
	(in thousands)	2013			2012			2011
	Deferred tax (benefit) expense	$	(19,597	)	$	(15,190	)	$	13,396
	Federal deferred tax benefit relating to the exercise of stock options		(—	)		(—	)		(—	)
	Increase (decrease) in the valuation allowance for deferred tax asset		19,597			15,190			(13,396	)
		$	—		$	—		$	—
	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at December 31, 2013 and 2012 are presented below.
	(in thousands)	31-Dec-13			31-Dec-12
	Deferred tax assets (liabilities):
	Net operating loss carryforwards	$	149,510		$	133,677
	Non-cash compensation		7,022			6,478
	Unrealized / realized loss on securities		1,164			1,164
	Capitalized Inventory		3,061			—
	Research and development		2,088			1,684
	Intangible assets due to different amortization methods		(135	)		63
	Accrued expenses		53			100
	Other temporary differences		11			10
	Deferred tax asset, excluding valuation allowance		162,774			143,176
	Less valuation allowance		(162,774	)		(143,176	)
	Net deferred tax assets	$	—		$	—
	We file income tax returns in the U.S federal and various state and local jurisdictions. For federal and state income tax purposes, the 2010, 2011 and 2012 tax years remain open for examination under the normal three year statute of limitations. The statute of limitations for income tax audits in the U.S. will commence upon utilization of net operating losses and will expire three years from the filing of the tax return.
	There was no accrual for uncertain tax positions or for interest and penalties related to uncertain tax positions for 2013, 2012 and 2011. We do not believe that there will be a material change in our unrecognized tax positions over the next twelve months. All of the unrecognized tax benefits, if recognized, would be offset by the valuation allowance.

Interest_and_Other_Income_Net

Interest and Other Income, Net	12 Months Ended
	Dec. 31, 2013
Interest and Other Income, Net	'
	NOTE 13 - INTEREST AND OTHER INCOME, NET
	The components of interest and other income, net are as follows:
		For the year ended December 31,
	(in thousands)	2013		2012		2011
	Interest income	$	190	$	52	$	159
	Other income		161		166		221
	Compensatory damage award, net		—		1,501		—
		$	351	$	1,719	$	380
	In 2012, we recorded other income due to the award of $1.5 million in compensatory damages, net of fees and legal expenses, relating to the statement of claim we filed with the Financial Institution Regulatory Authority against an SEC registered broker-dealer for damages arising from that broker-dealer’s recommendations and purchases of auction rate securities for our cash management account.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies	'
	NOTE 14 - COMMITMENTS AND CONTINGENCIES
	Research and Development Agreements
	We have entered into various research and development agreements (relating to our development of Zerenex) under which we are obligated to make payments of approximately $19,921,000 through 2016. The following table shows future research and development payment obligations by period as of December 31, 2013.
	(in thousands)	2014		2015		2016		2017		2018
	Research and development agreements	$	19,629	$	254	$	38		—		—
	The above table includes a $14,817,000 commitment for inventory build in 2014. The capitalization of inventory for our product candidate will commence when it is probable that our product will be approved for commercial marketing.
	Most of the commitments in the table above are contingent upon our continuing development of Zerenex.
	Leases
	In March and September 2013, we extended our lease on our corporate and executive office located in New York City, adding approximately 6,800 square feet of additional leased space and extending its term through September 30, 2016. We also executed an amendment to our office sharing agreement with a third party for a portion of our leased space through September 29, 2014.
	Total rental expense was approximately $667,000, $537,000 and $538,000 for the years ended December 31, 2013, 2012, and 2011, respectively. We recognized sublet income of $161,000, $166,000 and $221,000 for the years ended December 31, 2013, 2012, and 2011, respectively, related to the office sharing agreement.
	Future minimum lease commitments as of December 31, 2013, in the aggregate total approximately $2,848,000 through September 2016. The following table shows future minimum lease commitments by period as of December 31, 2013.
	(in thousands)	2014		2015		2016		2017		2018
	Operating leases	$	949	$	1,045	$	854		—		—
	The remaining sublet income of $120,600 is not included as an offset to our operating lease obligations in the table above.
	Royalty and Contingent Milestone Payments
	We have licensed the patent rights to Zerenex from a third party. The license agreement requires us to make contingent milestone payments to the licensor of up to $7.0 million over the life of the license, which will be due upon the regulatory approvals of Zerenex in the U.S., EU and Japan. The uncertainty relating to the timing of regulatory approvals prevents us from including the entire commitment in the Research and Development table above. Subsequent to December 31, 2013, we paid a $2.0 million milestone payment to the licensor of Zerenex relating to the marketing approval of ferric citrate in Japan in January 2014, which is not included in the above table. In addition, under the license agreement, we must pay royalties on net sales of Zerenex.

Litigation

Litigation	12 Months Ended
	Dec. 31, 2013
Litigation	'
	NOTE 15 - LITIGATION
	In October 2009, we filed a statement of claim with the Financial Institution Regulatory Authority, or FINRA, to commence an arbitration proceeding against an SEC registered broker-dealer. In this arbitration proceeding, we sought damages arising from that broker-dealer’s recommendations and purchases of auction rate securities for our cash management account. On May 7, 2012, we received the arbitrators’ award, which required the broker-dealer to pay us compensatory damages in the amount of approximately $1.8 million. In June 2012, we received the award, which amounted to, after fees and legal expenses, approximately $1.5 million.
	On February 1, 2013, a lawsuit was filed against us and our chief executive officer on behalf of a putative class of all of our shareholders (other than the defendants) who acquired our shares between June 1, 2009 and April 1, 2012. Smith v. Keryx Biopharmaceuticals, Inc., et al., Case No. 1:13-CV-0755-TPG (S.D.N.Y.). On February 26, 2013, a substantially similar lawsuit was filed against us and our chief executive officer as well as our chief financial officer. Park v. Keryx Biopharmaceuticals, Inc., et al., Case No. 1:13-CV-1307-TPG (S.D.N.Y.). On June 10, 2013, the Court entered an Order consolidating the two lawsuits and appointing a lead plaintiff. The case is now styled In re Keryx Biopharmaceuticals, Inc. Securities Litigation, Case No. 1:13-CV-0755-KBF (S.D.N.Y.). On July 10, 2013, the lead plaintiff filed a Consolidated Amended Complaint that, in substance, repeated the claims alleged in the consolidated lawsuits. The Consolidated Amended Complaint asserts claims against (i) us for alleged violations of Section 10(b) of the Securities Exchange Act of 1934 (“Exchange Act”) and Rule 10b-5 promulgated thereunder and (ii) our chief executive officer for alleged violations of Sections 10(b) and 20(a) of the Exchange Act and Rule 10b-5. The claims in the Consolidated Amended Complaint are premised on general allegations that we and the individual defendant participated directly or indirectly in the preparation and/or issuance of purportedly false and misleading earnings reports, SEC filings, press releases, and other public statements, which allegedly caused our stock to trade at artificially inflated prices. The lead plaintiff seeks an unspecified amount of damages. On August 26, 2013, we filed a motion to dismiss the Consolidated Amended Complaint. On October 10, 2013, lead plaintiff filed an opposition to our motion to dismiss. Our reply in further support of our motion to dismiss was filed on November 12, 2013. On February 14, 2014, the Court entered an Opinion and Order granting the motion to dismiss. The Court entered Judgment for the Defendants on February 24, 2014. We believe the claims made in this action are without merit, and intend to defend the consolidated action vigorously. We cannot, however, predict the outcome or effect, if any, of the lawsuit on our business.

Quarterly_Consolidated_Financi

Quarterly Consolidated Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2013
Quarterly Consolidated Financial Data (Unaudited)	'
	NOTE 16 - QUARTERLY CONSOLIDATED FINANCIAL DATA (UNAUDITED)
		2013
		Mar. 31			30-Jun			Sept. 30			Dec. 31
		(in thousands, except per share data)
	Revenue:
	License revenue	$	7,000		$	—		$	—		$	—
	Total revenue		7,000			—			—			—
	Operating expenses:
	Research and development:
	Non-cash compensation		191			243			319			1,594
	Other research and development		6,239			6,934			10,351			8,863
	Total research and development		6,430			7,177			10,670			10,457
	General and administrative:
	Non-cash compensation		390			395			422			2,399
	Other general and administrative		2,338			3,882			4,640			4,883
	Total general and administrative		2,728			4,277			5,062			7,282
	Total operating expenses		9,158			11,454			15,732			17,739
	Operating loss		(2,158	)		(11,454	)		(15,732	)		(17,739	)
	Other income
	Interest and other income, net		103			96			81			71
	Loss before income taxes		(2,055	)		(11,358	)		(15,651	)		(17,668	)
	Income taxes		—			—			—			—
	Net loss	$	(2,055	)	$	(11,358	)	$	(15,651	)	$	(17,668	)
	Basic and diluted net loss per common share	$	(0.03	)	$	(0.14	)	$	(0.19	)	$	(0.21	)
		2012
		Mar. 31			30-Jun			Sept. 30			Dec. 31
		(in thousands, except per share data)
	Operating expenses:
	Research and development:
	Non-cash compensation	$	278		$	73		$	161		$	150
	Other research and development		7,122			3,726			3,768			4,753
	Total research and development		7,400			3,799			3,929			4,903
	General and administrative:
	Non-cash compensation		368			365			384			388
	Other general and administrative		1,408			1,535			1,213			1,387
	Total general and administrative		1,776			1,900			1,597			1,775
	Total operating expenses		9,176			5,699			5,526			6,678
	Operating loss		(9,176	)		(5,699	)		(5,526	)		(6,678	)
	Other income
	Interest and other income, net		62			1,556			51			50
	Loss before income taxes and extraordinary gain		(9,114	)		(4,143	)		(5,475	)		(6,628	)
	Income taxes		—			—			—			—
	Loss before extraordinary gain		(9,114	)		(4,143	)		(5,475	)		(6,628	)
	Extraordinary gain		—			2,639			—			—
	Net loss	$	(9,114	)	$	(1,504	)	$	(5,475	)	$	(6,628	)
	Basic and diluted net loss per common share
	Before extraordinary gain		(0.13	)		(0.06	)		(0.08	)		(0.09	)
	Extraordinary gain		—			0.04			—			—
	Basic and diluted net loss per common share	$	(0.13	)	$	(0.02	)	$	(0.08	)	$	(0.09	)

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2013
Subsequent Events	'
	NOTE 17 - SUBSEQUENT EVENTS
	On January 22, 2014, we announced the pricing of an underwritten public offering, whereby we sold 7,935,000 shares of our common stock at a price of $14.50 per share for gross proceeds of approximately $115.1 million. Net proceeds from this offering were approximately $107.6 million, net of underwriting discounts and offering expenses of approximately $7.5 million. The shares were sold under a Registration Statement (No. 333-190353) on Form S-3, filed by us with the Securities and Exchange Commission.
	In January 2014, our Japanese partner, JT and Torii, received manufacturing and marketing approval of ferric citrate from the Japanese Ministry of Health, Labour and Welfare. Ferric citrate, to be marketed in Japan by JT’s subsidiary, Torii, under the brand name Riona®, is indicated as an oral treatment for the improvement of hyperphosphatemia in patients with CKD. Under the license agreement with JT and Torii, Keryx received a non-refundable payment of $10.0 million in February 2014 for the achievement of the marketing approval milestone. Keryx will also receive double-digit tiered royalties on net sales of Riona® in Japan, as well as up to an additional $55.0 million upon the achievement of certain annual net sales milestones.

Organization_and_Summary_of_Si1

Organization and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Description of Business	'
	DESCRIPTION OF BUSINESS
	We are a biopharmaceutical company focused on the acquisition, development and commercialization of pharmaceutical products for the treatment of renal disease. Currently, our only drug candidate is ZerenexTM (ferric citrate coordination complex), an oral, ferric iron-based compound. Our New Drug Application (“NDA”), for the treatment of hyperphosphatemia (elevated phosphate levels) in patients with chronic kidney disease (“CKD”) on dialysis, is currently under review by the Food and Drug Administration (“FDA”) with an assigned Prescription Drug User Fee Act (“PDUFA”) goal date of June 7, 2014. In addition, in March 2014, we submitted a Marketing Authorization Application (“MAA”) with the European Medicines Agency (“EMA”) seeking the approval of Zenerex as a treatment for hyperphosphatemia in patients with CKD, including dialysis and non-dialysis dependent CKD.
	We own a 100% interest in each of ACCESS Oncology, Inc. (“ACCESS Oncology”), Neryx Biopharmaceuticals, Inc., and Accumin Diagnostics, Inc. (“ADI”), all inactive U.S. corporations incorporated in the State of Delaware. Most of our biopharmaceutical development and substantially all of our administrative operations during 2013, 2012 and 2011 were conducted in the U.S.
Liquidity and Capital Resources	'
	LIQUIDITY AND CAPITAL RESOURCES
	Except for 2009, we have incurred substantial operating losses since our inception, and expect to continue to incur operating losses for the foreseeable future and may never become profitable. As of December 31, 2013, we have an accumulated deficit of $439.3 million.
	Our major sources of cash have been proceeds from various public and private offerings of our common stock, option and warrant exercises, interest income, and from the upfront and milestone payments from our Sublicense Agreement with Japan Tobacco Inc. (“JT”) and Torii Pharmaceutical Co., Ltd. (“Torii”) and miscellaneous payments from our other prior licensing activities. We have not yet commercialized any drug candidate and cannot be sure if we will ever be able to do so. Even if we commercialize a drug candidate, we may not become profitable. Our ability to achieve profitability depends on a number of factors, including our ability to complete our development efforts, obtain regulatory approval for our drug candidate, successfully complete any post-approval regulatory obligations and successfully manufacture and commercialize our drug candidate alone or in partnership. We may continue to incur substantial operating losses even if we begin to generate revenues from our drug candidate, if approved.
	In January 2013, we raised approximately $74.8 million, net of underwriting discounts and offering expenses of approximately $5.6 million, in an underwritten public offering. In January 2014, we raised approximately $107.6 million, net of underwriting discounts and offering expenses of approximately $7.5 million, in an underwritten public offering. We have a shelf registration statement on Form S-3 filed and declared effective by the Securities and Exchange Commission in August 2013, which provides for the offering of up to $150 million of common stock and warrants in the aggregate. Subsequent to the underwritten public offerings that were completed in January 2013 and January 2014, there remains approximately $34.9 million of our common stock and warrants available for sale on this shelf registration statement.
	We currently expect that our existing capital resources combined with future anticipated cash flows will be sufficient to operate our business plan. The actual amount of cash that we will need to operate is subject to many factors, including, but not limited to, the timing and expenditures associated with the build-up of prelaunch/launch inventory and capacity expansion, the timing and expenditures associated with the respective regulatory review processes for our U.S. NDA and EU MAA filings, the timing and expenditures associated with pre-commercial/commercial activities related to Zerenex, and the timing, design and conduct of clinical trials for Zerenex. We may depend upon significant additional financings to provide the cash necessary to execute our current operations, including the commercialization of Zerenex.
	Our common stock is listed on the NASDAQ Capital Market and trades under the symbol “KERX.”
Corporate	'
	CORPORATE
	In September 2013, the Board of Directors increased the total number of board members to seven and appointed Daniel P. Regan as a director to fill the newly-created position.
	In February 2014, Greg Madison was appointed as Executive Vice President and Chief Operating Officer.
Recently Issued Accounting Standards	'
	RECENTLY ISSUED ACCOUNTING STANDARDS
	None.
Principles of Consolidation	'
	PRINCIPLES OF CONSOLIDATION
	The consolidated financial statements include our financial statements and those of our wholly-owned subsidiaries. Intercompany transactions and balances have been eliminated in consolidation.
Use of Estimates	'
	USE OF ESTIMATES
	The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the applicable reporting period. Actual results could differ from those estimates. Such differences could be material to the financial statements.
Cash and Cash Equivalents	'
	CASH AND CASH EQUIVALENTS
	We treat liquid investments with original maturities of three months or less when purchased as cash and cash equivalents.
Investment Securities	'
	INVESTMENT SECURITIES
	We were not invested in investment securities at December 31, 2013 and 2012, respectively.
Property, Plant and Equipment	'
	PROPERTY, PLANT AND EQUIPMENT
	Property, plant and equipment are stated at historical cost. Depreciation is computed using the straight-line method over the estimated useful lives of the assets:
		Estimated
		useful life
		(years)
	Office furniture and equipment	7-Mar
	Computers, software and related equipment	3
	Leasehold improvements are amortized over the shorter of their useful life or the remaining term of the lease exclusive of renewal options.
Patent Costs	'
	PATENT COSTS
	We expense patent maintenance costs as incurred. We have classified our patent expenses in other general and administrative.
Revenue Recognition	'
	REVENUE RECOGNITION
	We recognize license revenue in accordance with the revenue recognition guidance of the FASB Accounting Standards Codification (the “Codification”). We analyze each element of our licensing agreement to determine the appropriate revenue recognition. The terms of the license agreement may include payments to us of non-refundable up-front license fees, milestone payments if specified objectives are achieved, and/or royalties on product sales. We recognize revenue from upfront payments over the period of significant involvement under the related agreements unless the fee is in exchange for products delivered or services rendered that represent the culmination of a separate earnings process and no further performance obligation exists under the contract. We recognize milestone payments as revenue upon the achievement of specified milestones only if (1) the milestone payment is non-refundable, (2) substantive effort is involved in achieving the milestone, (3) the amount of the milestone is reasonable in relation to the effort expended or the risk associated with achievement of the milestone, and (4) the milestone is at risk for both parties. If any of these conditions are not met, we defer the milestone payment and recognize it as revenue over the estimated period of performance under the contract (see Note 9 – License Agreements).
	Other revenue consists of fees and payments arising from technology transfer, termination and settlement agreements related to our prior license agreements. Other revenues are recognized at the time such fees and payments are earned.
Research and Development Costs	'
	RESEARCH AND DEVELOPMENT COSTS
	Research and development costs are expensed as incurred. Pre-approval inventory expenditures are recorded as research and development expense as incurred. The capitalization of inventory for our product candidate will commence when it is probable that our product will be approved for commercial marketing. Nonrefundable advance payments for goods or services that will be used or rendered for future research and development activities are deferred and amortized over the period that the goods are delivered or the related services are performed, subject to an assessment of recoverability. We make estimates of costs incurred in relation to external clinical research organizations (“CROs”) and clinical site costs. We analyze the progress of clinical trials, including levels of patient enrollment, invoices received and contracted costs when evaluating the adequacy of the amount expensed and the related prepaid asset and accrued liability. Significant judgments and estimates must be made and used in determining the accrued balance and expense in any accounting period. We review and accrue CRO expenses and clinical trial study expenses based on work performed and rely upon estimates of those costs applicable to the stage of completion of a study. Accrued CRO costs are subject to revisions as such trials progress to completion. Revisions are charged to expense in the period in which the facts that give rise to the revision become known. With respect to clinical site costs, the financial terms of these agreements are subject to negotiation and vary from contract to contract. Payments under these contracts may be uneven, and depend on factors such as the achievement of certain events, the successful recruitment of patients, the completion of portions of the clinical trial or similar conditions. The objective of our policy is to match the recording of expenses in our financial statements to the actual services received and efforts expended. As such, expense accruals related to clinical site costs are recognized based on our estimate of the degree of completion of the event or events specified in the specific clinical study or trial contract.
Income Taxes	'
	INCOME TAXES
	Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, operating losses and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. If the likelihood of realizing the deferred tax assets or liability is less than “more likely than not,” a valuation allowance is then created.
	We, and our subsidiaries, file income tax returns in the U.S. federal jurisdiction and in various states. We have tax net operating loss carryforwards that are subject to examination for a number of years beyond the year in which they were generated for tax purposes. Since a portion of these net operating loss carryforwards may be utilized in the future, many of these net operating loss carryforwards will remain subject to examination.
	We are continuing our practice of recognizing interest and penalties related to uncertain income tax positions in income tax expense.
Stock - Based Compensation	'
	STOCK - BASED COMPENSATION
	We recognize all share-based payments to employees and to non-employee directors for service on our board of directors as compensation expense in the consolidated financial statements based on the grant date fair values of such payments. Stock-based compensation expense recognized each period is based on the value of the portion of share-based payment awards that is ultimately expected to vest during the period. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates.
	For share-based payments to consultants and other third-parties, compensation expense is determined at the “measurement date.” The expense is recognized over the vesting period of the award. Until the measurement date is reached, the total amount of compensation expense remains uncertain. We record compensation expense based on the fair value of the award at the reporting date. The awards to consultants and other third-parties are then revalued, or the total compensation is recalculated based on the then current fair value, at each subsequent reporting date.
Basic and Diluted Net Loss Per Common Share	'
	BASIC AND DILUTED NET LOSS PER COMMON SHARE
	Basic net loss per share is computed by dividing the losses allocable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss per share does not reflect the effect of shares of common stock to be issued upon the exercise of stock options and warrants, as their inclusion would be anti-dilutive. The options outstanding as of December 31, 2013, 2012 and 2011, which are not included in the computation of net loss per share amounts, were 3,845,370, 3,401,671 and 3,517,000, respectively. No warrants were outstanding during each of these periods.
Segment Reporting	'
	SEGMENT REPORTING
	Following the discontinuation of the Services segment in December 2011, we have determined that we operate in only one reportable segment: the Products segment.
Acquisitions	'
	ACQUISITIONS
	We adopted ASC Topic 805, Business Combinations, as of January 1, 2009. The adoption of ASC Topic 805 was effective on a prospective basis. Prior to the adoption of ASC Topic 805, we accounted for acquired businesses using the purchase method of accounting which required that the assets acquired and liabilities assumed be recorded at the date of acquisition at their respective fair values. Our consolidated financial statements and results of operations through 2008 reflected an acquired business after the completion of the acquisition and were not retroactively restated. The cost to acquire a business, including transaction costs, was allocated to the underlying net assets of the acquired business in proportion to their respective fair values. Any excess of the purchase price over the estimated fair values of the net assets acquired was recorded as goodwill. Any excess of the net assets acquired over the purchase price represented negative goodwill.
Impairment	'
	IMPAIRMENT
	Long lived assets are reviewed for an impairment loss when circumstances indicate that the carrying value of long-lived tangible and intangible assets with finite lives may not be recoverable. Management’s policy in determining whether an impairment indicator exists, a triggering event, comprises measurable operating performance criteria as well as qualitative measures. If an analysis is necessitated by the occurrence of a triggering event, we make certain assumptions in determining the impairment amount. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future cash flows expected to be generated by the asset or used in its disposal. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized.
	Goodwill is reviewed for impairment annually, or when events arise that could indicate that an impairment exists. We test for goodwill impairment using a two-step process. The first step compares the fair value of the reporting unit with the unit’s carrying value, including goodwill. When the carrying value of the reporting unit is greater than fair value, the unit’s goodwill may be impaired, and the second step must be completed to measure the amount of the goodwill impairment charge, if any. In the second step, the implied fair value of the reporting unit’s goodwill is compared with the carrying amount of the unit’s goodwill. If the carrying amount is greater than the implied fair value, the carrying value of the goodwill must be written down to its implied fair value. As of December 31, 2011, 2012 and 2013, management conducted its annual assessments of goodwill and concluded that there were no impairments. We will continue to perform impairment tests annually, at December 31, and whenever events or changes in circumstances suggest that the carrying value of an asset may not be recoverable.
Concentrations of Credit Risk	'
	CONCENTRATIONS OF CREDIT RISK
	We do not have significant off-balance-sheet risk or credit risk concentrations. We maintain our cash and cash equivalents and held-to-maturity investments, when applicable, with multiple financial institutions that invest in investment-grade securities with average maturities of less than twelve months. See Note 3 – Investment Securities and Note 4 – Fair Value Measurements.

Organization_and_Summary_of_Si2

Organization and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Property Plant and Equipment Useful Life	'
	Depreciation is computed using the straight-line method over the estimated useful lives of the assets:
		Estimated
		useful life
		(years)
	Office furniture and equipment	7-Mar
	Computers, software and related equipment	3

Cash_and_Cash_Equivalents_Tabl

Cash and Cash Equivalents (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Cash and Cash Equivalents	'
	(in thousands)	31-Dec-13		31-Dec-12
	Money market funds	$	29,904	$	7,137
	Checking and bank deposits		25,792		7,540
	Total	$	55,696	$	14,677

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Measurements of Financial Assets	'
	The following table provides the fair value measurements of applicable financial assets as of December 31, 2013 and 2012:
			Financial assets at fair value
			as of December 31, 2013
	(in thousands)		Level 1		Level 2		Level 3
	Money market funds (1)		$	29,904	$	—	$	—
	Total		$	29,904	$	—	$	—
			Financial assets at fair value
			as of December 31, 2012
	(in thousands)		Level 1		Level 2		Level 3
	Money market funds (1)		$	7,137	$	—	$	—
	Total		$	7,137	$	—	$	—
	-1	Included in cash and cash equivalents on our consolidated balance sheet. The carrying amount of money market funds is a reasonable estimate of fair value.

Property_Plant_and_Equipment_T

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment	'
	(in thousands)	31-Dec-13			31-Dec-12
	Leasehold improvements	$	32		$	20
	Office furniture and equipment		556			329
	Computers, software and related equipment		638			530
			1,226			879
	Accumulated depreciation and amortization		(877	)		(823	)
	Net book value	$	349		$	56
Schedule of Depreciation Expense	'
	The following table summarizes depreciation expense for the years ended December 31, 2013, 2012 and 2011.
		For the year ended December 31
	(in thousands)	2013			2012			2011
	Depreciation expense:
	Research and development		32			21			28
	General and administrative		22			14			19
	Total	$	54		$	35		$	47

Other_Assets_Tables

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Other Assets, Noncurrent	'
	(in thousands)	31-Dec-13			31-Dec-12
	Patents and other indefinite-lived intangible assets	$	352		$	352
	Deposits		163			163
	Deferred registration fees		118			35
			633			550
	Accumulated amortization		(352	)		(352	)
		$	281		$	198

Discontinued_Operations_Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Disposal Groups, Including Discontinued Operations, Income Statement	'
	Summarized selected financial information for discontinued operations are as follows:
		For the year ended December 31
	(in thousands)	2013		2012		2011
	Service revenue	$	—	$	—	$	156
	Operating expenses:
	Cost of services		—		—		(90	)
	Total operating income		—		—		246
	Gain from discontinued operations	$	—	$	—	$	246

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2013
Summary of Stock Option Activity	'
	The following table summarizes stock option activity for all plans for the years ended December 31, 2013, 2012 and 2011:
		Number			Weighted-		Weighted-		Aggregate
		of shares			average		average		Intrinsic
					exercise		Contractual		Value
					price		Term
	Outstanding at January 1, 2011		7,638,403		$	7.05
	Granted		692,350			4.53
	Exercised		(2,382,027	)		1.3			$	6,604,300
	Forfeited		(98,600	)		4.32
	Expired		(2,333,126	)		13.26
	Outstanding at December 31, 2011		3,517,000			6.4			$	2,139,130
	Granted		521,500			2.36
	Exercised		—			—			$	—
	Forfeited		(266,621	)		7.77
	Expired		(370,208	)		11.02
	Outstanding at December 31, 2012		3,401,671			5.17			$	2,373,509
	Granted		932,366			6.29
	Exercised		(443,813	)		2.1			$	4,614,741
	Forfeited		(44,854	)		8.7
	Expired		—			—
	Outstanding at December 31, 2013		3,845,370		$	5.75		6.2	$	28,361,438
	Vested and expected to vest at December 31, 2013		3,804,543		$	5.76		6.2	$	28,045,772
	Exercisable at December 31, 2013		2,519,162		$	5.74		5	$	18,719,371
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range	'
	The following table summarizes information about stock options outstanding at December 31, 2013:
		Options outstanding							Options exercisable
	Range of exercise prices	Number			Weighted-		Weighted-		Number		Weighted-
		outstanding			average		average		exercisable		average
					remaining		exercise				exercise
					contractual		price				price
					life (years)
	$ 0.10 - $ 3.00		1,698,612			7	$	1.64		1,078,621	$	1.11
	3.70 - 8.56		1,106,208			7.5		5.74		656,991		4.94
	9.34 - 14.64		1,040,550			3.5		12.48		783,550		12.78
	$ 0.10 - $ 14.64		3,845,370			6.2	$	5.75		2,519,162	$	5.74
Summary of Restricted Share Activity	'
	The following table summarizes restricted share activity for the years ended December 31, 2013, 2012 and 2011:
		Number			Weighted		Aggregate
		of Shares			Average		Intrinsic
					Grant		Value
					Date Fair
					Value
	Outstanding at January 1, 2011		1,400,694		$	1.63	$	6,415,179
	Granted		206,450			4.49
	Vested		(957,225	)		1.2	$	4,650,171
	Forfeited		(28,338	)		3.35
	Outstanding at December 31, 2011		621,581			3.16	$	1,572,600
	Granted		997,300			1.94
	Vested		(339,954	)		2.91	$	965,496
	Forfeited		(97,250	)		2.33
	Outstanding at December 31, 2012		1,181,677			2.27	$	3,095,994
	Granted		831,020			7.68
	Vested		(568,030	)		2.43	$	4,612,275
	Forfeited		(23,737	)		8.52
	Outstanding at December 31, 2013		1,420,930		$	5.27	$	18,401,044
Black-Scholes Option Valuation Assumptions	'
	Black-Scholes Option Valuation Assumptions	2013		2012	2011
	Risk-free interest rates	0.70%		0.60%	1.40%
	Dividend yield	—		—	—
	Volatility	102.00%		106.30%	115.00%
	Weighted-average expected term	3.8 years		4.0 years	4.0 years
Schedule of Share Based Compensation Expense	'
	The following table summarizes stock-based compensation expense information about stock options and restricted stock for the years ended December 31, 2013, 2012 and 2011:
		For the year ended December 31,
	(in thousands)	2013			2012		2011
	Stock-based compensation expense associated with restricted stock	$	3,859		$	967	$	1,044
	Stock-based compensation expense associated with option grants		2,094			1,200		1,048
		$	5,953		$	2,167	$	2,092

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Effective Income Tax Rate Reconciliation	'
	Income tax expense differed from amounts computed by applying the US federal income tax rate of 34% to pretax loss as follows:
		For the year ended
		December 31,
	(in thousands)	2013			2012			2011
	Loss from continuing operations before income taxes, as reported in the consolidated statements of operations	$	(46,732	)	$	(25,360	)	$	(28,369	)
	Computed “expected” tax (benefit) expense		(15,889	)		(8,622	)		(9,645	)
	Increase (decrease) in income taxes resulting from:
	Expected (benefit) expense from state & local taxes		(1,523	)		(827	)		(925	)
	Stock compensation		(1,842	)		905			5,872
	Deferred impact rate change		—			—			19,072
	Permanent differences		66			(196	)		(147	)
	Other		—			—			(2	)
	Prior year true-up		(409	)		(6,450	)		(829	)
	Change in the balance of the valuation allowance for deferred tax assets allocated to income tax expense		19,597			15,190			(13,396	)
		$	—		$	—		$	—
Schedule of Components of Income Tax Expense (Benefit)	'
	The significant components of deferred income tax expense (benefit) attributable to loss from operations are as follows:
		For the year ended
		December 31,
	(in thousands)	2013			2012			2011
	Deferred tax (benefit) expense	$	(19,597	)	$	(15,190	)	$	13,396
	Federal deferred tax benefit relating to the exercise of stock options		(—	)		(—	)		(—	)
	Increase (decrease) in the valuation allowance for deferred tax asset		19,597			15,190			(13,396	)
		$	—		$	—		$	—
Schedule of Deferred Tax Assets and Liabilities	'
	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities at December 31, 2013 and 2012 are presented below.
	(in thousands)	31-Dec-13			31-Dec-12
	Deferred tax assets (liabilities):
	Net operating loss carryforwards	$	149,510		$	133,677
	Non-cash compensation		7,022			6,478
	Unrealized / realized loss on securities		1,164			1,164
	Capitalized Inventory		3,061			—
	Research and development		2,088			1,684
	Intangible assets due to different amortization methods		(135	)		63
	Accrued expenses		53			100
	Other temporary differences		11			10
	Deferred tax asset, excluding valuation allowance		162,774			143,176
	Less valuation allowance		(162,774	)		(143,176	)
	Net deferred tax assets	$	—		$	—

Interest_and_Other_Income_Net_

Interest and Other Income, Net (Tables)	12 Months Ended
	Dec. 31, 2013
Schedule of Other Nonoperating Income (Expense)	'
	The components of interest and other income, net are as follows:
		For the year ended December 31,
	(in thousands)	2013		2012		2011
	Interest income	$	190	$	52	$	159
	Other income		161		166		221
	Compensatory damage award, net		—		1,501		—
		$	351	$	1,719	$	380

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Contractual Obligations, Fiscal Year Maturity Schedule	'
	The following table shows future research and development payment obligations by period as of December 31, 2013.
	(in thousands)	2014		2015		2016		2017		2018
	Research and development agreements	$	19,629	$	254	$	38		—		—
Schedule of Future Minimum Rental Payments for Operating Leases	'
	The following table shows future minimum lease commitments by period as of December 31, 2013.
	(in thousands)	2014		2015		2016		2017		2018
	Operating leases	$	949	$	1,045	$	854		—		—

Quarterly_Consolidated_Financi1

Quarterly Consolidated Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Consolidated Financial Data	'
		2013
		Mar. 31			30-Jun			Sept. 30			Dec. 31
		(in thousands, except per share data)
	Revenue:
	License revenue	$	7,000		$	—		$	—		$	—
	Total revenue		7,000			—			—			—
	Operating expenses:
	Research and development:
	Non-cash compensation		191			243			319			1,594
	Other research and development		6,239			6,934			10,351			8,863
	Total research and development		6,430			7,177			10,670			10,457
	General and administrative:
	Non-cash compensation		390			395			422			2,399
	Other general and administrative		2,338			3,882			4,640			4,883
	Total general and administrative		2,728			4,277			5,062			7,282
	Total operating expenses		9,158			11,454			15,732			17,739
	Operating loss		(2,158	)		(11,454	)		(15,732	)		(17,739	)
	Other income
	Interest and other income, net		103			96			81			71
	Loss before income taxes		(2,055	)		(11,358	)		(15,651	)		(17,668	)
	Income taxes		—			—			—			—
	Net loss	$	(2,055	)	$	(11,358	)	$	(15,651	)	$	(17,668	)
	Basic and diluted net loss per common share	$	(0.03	)	$	(0.14	)	$	(0.19	)	$	(0.21	)
		2012
		Mar. 31			30-Jun			Sept. 30			Dec. 31
		(in thousands, except per share data)
	Operating expenses:
	Research and development:
	Non-cash compensation	$	278		$	73		$	161		$	150
	Other research and development		7,122			3,726			3,768			4,753
	Total research and development		7,400			3,799			3,929			4,903
	General and administrative:
	Non-cash compensation		368			365			384			388
	Other general and administrative		1,408			1,535			1,213			1,387
	Total general and administrative		1,776			1,900			1,597			1,775
	Total operating expenses		9,176			5,699			5,526			6,678
	Operating loss		(9,176	)		(5,699	)		(5,526	)		(6,678	)
	Other income
	Interest and other income, net		62			1,556			51			50
	Loss before income taxes and extraordinary gain		(9,114	)		(4,143	)		(5,475	)		(6,628	)
	Income taxes		—			—			—			—
	Loss before extraordinary gain		(9,114	)		(4,143	)		(5,475	)		(6,628	)
	Extraordinary gain		—			2,639			—			—
	Net loss	$	(9,114	)	$	(1,504	)	$	(5,475	)	$	(6,628	)
	Basic and diluted net loss per common share
	Before extraordinary gain		(0.13	)		(0.06	)		(0.08	)		(0.09	)
	Extraordinary gain		—			0.04			—			—
	Basic and diluted net loss per common share	$	(0.13	)	$	(0.02	)	$	(0.08	)	$	(0.09	)

Organization_and_Summary_of_Si3

Organization and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)

1 Months Ended

12 Months Ended

1 Months Ended

Sep. 30, 2013

Aug. 31, 2013

4-May-11

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Jan. 30, 2013

Jan. 22, 2014

Jan. 22, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Person

Segment

Maximum

Public offering

Subsequent Event

Subsequent Event

Access Oncology, Inc

Neryx Biopharmaceuticals, Inc

Accumin Diagnostics, Inc

Public offering

Organization Consolidation And Presentation Of Financial Statements [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

Ownership interest

'

'

'

'

'

'

'

'

'

'

100.00%

100.00%

100.00%

Accumulated deficit

'

'

'

($439,340,000)

($392,608,000)

'

'

'

'

'

'

'

'

Proceeds from public offering, net

'

'

30,700,000

74,753,000

'

30,734,000

'

74,753,000

'

107,600,000

'

'

'

Underwriting discounts and offering expenses

'

'

2,300,000

5,640,000

'

2,266,000

'

5,640,000

'

7,500,000

'

'

'

Shelf registration statements, offering maximum amount of common stock and warrant

'

$150,000,000

'

'

'

'

'

'

$34,900,000

'

'

'

'

Number of board members

7

'

'

'

'

'

'

'

'

'

'

'

'

Liquid investments, original maturities

'

'

'

'

'

'

'3 months

'

'

'

'

'

'

Option outstanding, not included in computation of net loss per share amount

'

'

'

3,845,370

3,401,671

3,517,000

'

'

'

'

'

'

'

Number of warrants outstanding

'

'

'

0

0

0

'

'

'

'

'

'

'

Number of reportable segments

'

'

'

1

'

'

'

'

'

'

'

'

'

Property_Plant_and_Equipment_U

Property Plant and Equipment Useful Life (Detail)	12 Months Ended
	Dec. 31, 2013
Office Furniture and Equipment | Minimum	'
Property, Plant and Equipment [Line Items]	'
Property, Plant and Equipment, Useful Life	'3 years
Office Furniture and Equipment | Maximum	'
Property, Plant and Equipment [Line Items]	'
Property, Plant and Equipment, Useful Life	'7 years
Computers, Software and Related Equipment	'
Property, Plant and Equipment [Line Items]	'
Property, Plant and Equipment, Useful Life	'3 years

Cash_And_Cash_Equivalents_Deta

Cash And Cash Equivalents (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Cash and Cash Equivalents [Line Items]	'	'
Money market funds	$29,904	$7,137
Checking and bank deposits	25,792	7,540
Total	$55,696	$14,677

Cash_And_Cash_Equivalents_Addi

Cash And Cash Equivalents - Additional Information (Detail) (USD $)	Dec. 31, 2013
In Millions, unless otherwise specified
Cash and Cash Equivalents [Line Items]	'
FDIC uninsured amount	$55.40

Fair_Value_Measurements_of_Fin

Fair Value Measurements of Financial Assets (Detail) (Level 1, USD $)	Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Financial assets at fair value	$29,904		$7,137
Money market funds	'		'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'		'
Financial assets at fair value	$29,904	[1]	$7,137	[1]
[1]	Included in cash and cash equivalents on our consolidated balance sheet. The carrying amount of money market funds is a reasonable estimate of fair value.

Property_Plant_and_Equipment_D

Property, Plant and Equipment (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Property, Plant and Equipment, Gross	$1,226	$879
Accumulated depreciation and amortization	-877	-823
Net book value	349	56
Leasehold improvements	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, Plant and Equipment, Gross	32	20
Office Furniture and Equipment	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, Plant and Equipment, Gross	556	329
Computers, Software and Related Equipment	'	'
Property, Plant and Equipment [Line Items]	'	'
Property, Plant and Equipment, Gross	$638	$530

Property_Plant_and_Equipment_A

Property, Plant and Equipment - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'
Depreciation	$54	$35	$47

Schedule_of_Depreciation_Expen

Schedule of Depreciation Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]	'	'	'
Depreciation	$54	$35	$47
Research and Development Expense	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Depreciation	32	21	28
General and Administrative Expense	'	'	'
Property, Plant and Equipment [Line Items]	'	'	'
Depreciation	$22	$14	$19

Goodwill_Additional_Informatio

Goodwill - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Apr. 06, 2006	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]	'	'	'
Business acquisition, date of acquisition agreement	'	6-Apr-06	'
Business acquisition purchase price	$3,996	'	'
Business Acquisition, purchase price allocation, goodwill amount	$3,208	$3,208	$3,208

Schedule_of_Other_Assets_Detai

Schedule of Other Assets (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Other Noncurrent Assets [Line Items]	'	'
Other assets gross	$633	$550
Accumulated amortization	-352	-352
Other assets, net	281	198
Patents and other indefinite-lived intangible assets	'	'
Other Noncurrent Assets [Line Items]	'	'
Other assets gross	352	352
Deposits	'	'
Other Noncurrent Assets [Line Items]	'	'
Other assets gross	163	163
Deferred registration fees	'	'
Other Noncurrent Assets [Line Items]	'	'
Other assets gross	$118	$35

Other_Assets_Additional_Inform

Other Assets - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Other Assets [Line Items]	'	'	'
Amortization expenses	$0	$0	$0

Discontinued_Operations_Additi

Discontinued Operations - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2011
Discontinued Operations [Line Items]	'
Reversal of previously recorded estimated liabilities associated with our discontinued operations	$246

Schedule_of_Disposal_Groups_In

Schedule of Disposal Groups, Including Discontinued Operations, Income Statement (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2011
Discontinued Operations [Line Items]	'
Service revenue	$156
Operating expenses:	'
Cost of services	-90
Total operating income	246
Gain from discontinued operations	$246

License_Agreements_Additional_

License Agreements - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended		1 Months Ended
	Jan. 31, 2013	Apr. 30, 2011	Mar. 31, 2013	Dec. 31, 2013	Dec. 31, 2011	Feb. 28, 2014	Jan. 31, 2014
						Subsequent Event	Subsequent Event
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]	'	'	'	'	'	'	'
License agreements, non-refundable milestone payment received	$7,000,000	$5,000,000	'	'	'	$10,000,000	'
License revenue	'	'	7,000,000	7,000,000	5,000,000	'	'
License agreements, potential milestone receivable	'	'	'	'	'	$55,000,000	$55,000,000

Contingent_Equity_Rights_Addit

Contingent Equity Rights - Additional Information (Detail) (USD $)	1 Months Ended		3 Months Ended	12 Months Ended			1 Months Ended
	4-May-11	Apr. 06, 2006	Jun. 30, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 16, 2009	Feb. 05, 2004
							Access Oncology, Inc	Access Oncology, Inc
Business Acquisition [Line Items]	'	'	'	'	'	'	'	'
Purchase price	'	$3,996,000	'	'	'	'	'	$19,502,000
Certain liabilities valued	'	'	'	'	'	'	'	8,723,000
Issuance of shares of common stock valued	'	'	'	'	'	'	'	6,325,000
Contingent equity rights valued	'	'	'	'	'	'	'	4,004,000
Transaction costs	'	'	'	'	'	'	'	450,000
Stock issued for acquisition	'	'	'	'	'	'	'	623,145
Stock issued for acquisition value	'	'	'	'	'	'	'	6,325,000
Stock issuable for stockholders	'	'	'	'	'	'	'	4,433
Stock issued during period, shares, new issues	7,021,277	'	'	'	'	'	500,000	'
Stock issued during period, value, new issues	'	'	'	74,753,000	'	30,734,000	1,365,000	'
Common stock rights outstanding shares maximum	'	'	'	2,872,422	'	'	'	'
Termination of license, non-cash extraordinary gain recognized	'	'	$2,639,000	'	$2,639,000	'	'	'

Stockholders_Equity_Additional

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

1 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

1 Months Ended

Aug. 31, 2013

4-May-11

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Jun. 18, 2013

Jun. 18, 2013

Jun. 18, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Jan. 22, 2014

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Jan. 30, 2013

Jan. 22, 2014

Before Amendment

After Amendment

Chief Executive Officer

Employee Stock Option

Restricted Stock

Restricted Stock

Restricted Stock

Restricted Stock

Restricted Stock

Stock Option

Stock Option

Stock Option

Stock Option

Subsequent Event

Maximum

Minimum

Stock Option Plan 1999

Stock Option Plan 1999

Long Term Incentive Plan 2004

Long Term Incentive Plan 2004

Incentive Plan 2007

Incentive Plan 2007

Incentive Plan 2013

Incentive Plan 2013

Unvested Milestone-Based Options

Unvested Milestone-Based Options

Unvested milestone-based employee awards

Unvested milestone based consultant awards

CEO Incentive Plan 2009

Milestone-based and vest upon certain corporate milestones

Milestone-based and vest upon certain corporate milestones

Scenario 1

Scenario 2

Scenario 2

Public offering

Public offering

Chief Executive Officer

Maximum

Maximum

Maximum

Maximum

Employee Stock Option

Non Employee Stock Options

Restricted Stock

Restricted Stock

Restricted Stock

Stock Option

Maximum

Subsequent Event

Stockholders Equity Note [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred stock, shares authorized

'

'

5,000,000

5,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred stock, par value

'

'

$0.00

$0.00

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common stock, shares authorized

'

'

130,000,000

95,000,000

'

'

95,000,000

130,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Common stock, par value

'

'

$0.00

$0.00

'

$0.00

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock issued during period, shares, new issues

'

7,021,277

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

9,469,100

7,935,000

Share price

'

$4.70

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$8.49

$14.50

Proceeds from issuance of common stock, gross

'

$33,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$80,400,000

$115,100,000

Proceeds from issuance of common stock, net

'

30,700,000

74,753,000

'

30,734,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

74,753,000

107,600,000

Underwriting discounts and offering expenses

'

2,300,000

5,640,000

'

2,266,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,640,000

7,500,000

Shelf registration statements, offering maximum amount of common stock and warrant

150,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

34,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Treasury stock, shares

'

'

79,948

79,948

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Treasury stock, value

'

'

357,000

357,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Plan authorizes grants to purchase common stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

4,230,000

'

4,000,000

'

6,000,000

'

3,500,000

'

'

'

'

'

600,000

'

'

'

'

'

'

'

Share based compensation arrangement by share based payment award contractual term

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'25 years

'

'10 years

'

'10 years

'

'10 years

'

'

'

'

'10 years

'

'

'

'

'

'

'

Shares available for the issuance of stock options

'

'

3,125,002

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0

'

244,165

'

9,837

'

2,871,000

'

'

'

'

'

'

'

'

'

'

'

'

Number of options

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3,845,370

3,401,671

3,517,000

7,638,403

'

'

'

'

'

'

'

'

'

'

'

77,500

50,000

'

'

'

'

127,500

'

'

'

'

'

Stock awards vesting period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'4 years

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'3 years

'

'

Restricted stock issued

'

'

'

'

'

'

'

'

'

'

1,420,930

1,181,677

621,581

1,400,694

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

390,000

100,000

'

490,000

'

'

'

'

'

'

Number of shares of restricted stock granted

'

'

'

'

'

'

'

'

'

'

'

'

'

'

750,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Employment agreement, termination date

'

'

'

'

'

'

'

'

'2015-05-20

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Number of shares of restricted stock to be granted

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000

100,000

'

'

'

Minimum non-refundable cash payment from outlicensing Zerenex in foreign market other than Japan to trigger granting of 100,000 shares of restricted stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

10,000,000

'

'

'

Gross deal value from outlicensing Zerenex in foreign market other than Japan to trigger granting of 100,000 shares of restricted stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50,000,000

'

'

'

Weighted average grant date fair value of options granted

'

'

$4.28

$1.73

$3.43

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total unrecognized compensation cost related to non-vest stock options

'

'

3,300,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Total unrecognized compensation cost related to restricted stock

'

'

'

'

'

'

'

'

'

'

$5,700,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Weighted average recognition periods for unrecognized compensation cost

'

'

'

'

'

'

'

'

'

'2 years 2 months 12 days

'2 years 7 months 6 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Summary_of_Stock_Option_Activi

Summary of Stock Option Activity (Detail) (Stock Option, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock Option	'	'	'
Number of shares	'	'	'
Outstanding at beginning of period	3,401,671	3,517,000	7,638,403
Granted	932,366	521,500	692,350
Exercised	-443,813	'	-2,382,027
Forfeited	-44,854	-266,621	-98,600
Expired	'	-370,208	-2,333,126
Outstanding at end of period	3,845,370	3,401,671	3,517,000
Vested and expected to vest at December 31, 2013	3,804,543	'	'
Exercisable at December 31, 2013	2,519,162	'	'
Weighted-average exercise price	'	'	'
Outstanding at beginning of period	$5.17	$6.40	$7.05
Granted	$6.29	$2.36	$4.53
Exercised	$2.10	'	$1.30
Forfeited	$8.70	$7.77	$4.32
Expired	'	$11.02	$13.26
Outstanding at end of period	$5.75	$5.17	$6.40
Vested and expected to vest at December 31, 2013	$5.76	'	'
Exercisable at December 31, 2013	$5.74	'	'
Weighted-average contractual term	'	'	'
Outstanding	'6 years 2 months 12 days	'	'
Vested and expected to vest at December 31, 2013	'6 years 2 months 12 days	'	'
Exercisable at December 31, 2013	'5 years	'	'
Aggregate intrinsic value	'	'	'
Outstanding at beginning of period	$2,373,509	$2,139,130	'
Exercised	4,614,741	'	6,604,300
Outstanding at end of period	28,361,438	2,373,509	2,139,130
Vested and expected to vest at December 31, 2013	28,045,772	'	'
Exercisable at December 31, 2013	$18,719,371	'	'

Stock_Options_Outstanding_Deta

Stock Options Outstanding (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Options outstanding, Range of exercise prices, Lower Limit	$0.10
Options outstanding, Range of exercise prices, Upper Limit	$14.64
Options outstanding, Number outstanding	3,845,370
Options outstanding, Weighted - average remaining contractual life	'6 years 2 months 12 days
Options outstanding, Weighed - average exercise price	$5.75
Options exercisable, Number exercisable	2,519,162
Options exercisable, Weighed - average exercise price	$5.74
$0.10 - $ 3.00	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Options outstanding, Range of exercise prices, Lower Limit	$0.10
Options outstanding, Range of exercise prices, Upper Limit	$3
Options outstanding, Number outstanding	1,698,612
Options outstanding, Weighted - average remaining contractual life	'7 years
Options outstanding, Weighed - average exercise price	$1.64
Options exercisable, Number exercisable	1,078,621
Options exercisable, Weighed - average exercise price	$1.11
$3.70 - $8.56	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Options outstanding, Range of exercise prices, Lower Limit	$3.70
Options outstanding, Range of exercise prices, Upper Limit	$8.56
Options outstanding, Number outstanding	1,106,208
Options outstanding, Weighted - average remaining contractual life	'7 years 6 months
Options outstanding, Weighed - average exercise price	$5.74
Options exercisable, Number exercisable	656,991
Options exercisable, Weighed - average exercise price	$4.94
$9.34 -14.64	'
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]	'
Options outstanding, Range of exercise prices, Lower Limit	$9.34
Options outstanding, Range of exercise prices, Upper Limit	$14.64
Options outstanding, Number outstanding	1,040,550
Options outstanding, Weighted - average remaining contractual life	'3 years 6 months
Options outstanding, Weighed - average exercise price	$12.48
Options exercisable, Number exercisable	783,550
Options exercisable, Weighed - average exercise price	$12.78

Summary_of_Restricted_Share_Ac

Summary of Restricted Share Activity (Detail) (Restricted Stock, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restricted Stock	'	'	'
Number of shares	'	'	'
Outstanding at beginning of period	1,181,677	621,581	1,400,694
Granted	831,020	997,300	206,450
Vested	-568,030	-339,954	-957,225
Forfeited	-23,737	-97,250	-28,338
Outstanding at end of period	1,420,930	1,181,677	621,581
Weighted average grant date fair value	'	'	'
Outstanding at beginning of period	$2.27	$3.16	$1.63
Granted	$7.68	$1.94	$4.49
Vested	$2.43	$2.91	$1.20
Forfeited	$8.52	$2.33	$3.35
Outstanding at end of period	$5.27	$2.27	$3.16
Aggregate intrinsic value	'	'	'
Outstanding at beginning of period	$3,095,994	$1,572,600	$6,415,179
Vested	$4,612,275	$965,496	$4,650,171
Outstanding at end of period	$18,401,044	$3,095,994	$1,572,600

Black_Scholes_Option_Valuation

Black Scholes Option Valuation Assumptions (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Risk-free interest rates	0.70%	0.60%	1.40%
Dividend yield	'	'	'
Volatility	102.00%	106.30%	115.00%
Weighted-average expected term	'3 years 9 months 18 days	'4 years	'4 years

Summary_of_Share_Based_Compens

Summary of Share Based Compensation Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'	'
Stock-based compensation expense associated with restricted stock	$3,859	$967	$1,044
Stock-based compensation expense associated with option grants	2,094	1,200	1,048
Stock compensation expense	$5,953	$2,167	$2,092

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]	'	'	'
Valuation allowance for deferred tax assets	$162,774,000	$143,176,000	'
Net operating loss carryforwards	401,300,000	'	'
Stock option exercises value included in U.S. net operating loss carryforwards	58,300,000	'	'
US Federal income tax rate	34.00%	'	'
Unrecognized tax benefits, accrued interest and penalties	$0	$0	$0
Minimum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration period	'2019	'	'
Maximum	'	'	'
Income Taxes [Line Items]	'	'	'
Net operating loss carryforwards, expiration period	'2032	'	'

Effective_Income_Tax_Rate_Reco

Effective Income Tax Rate Reconciliation (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Effective Tax Rate Reconciling Items [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Loss from continuing operations before income taxes, as reported in the consolidated statements of operations	($17,668)	($15,651)	($11,358)	($2,055)	($6,628)	($5,475)	($4,143)	($9,114)	($46,732)	($25,360)	($28,369)
Computed "expected" tax (benefit) expense	'	'	'	'	'	'	'	'	-15,889	-8,622	-9,645
Increase (decrease) in income taxes resulting from:	'	'	'	'	'	'	'	'	'	'	'
Expected (benefit) expense from state & local taxes	'	'	'	'	'	'	'	'	-1,523	-827	-925
Stock compensation	'	'	'	'	'	'	'	'	-1,842	905	5,872
Deferred impact rate change	'	'	'	'	'	'	'	'	'	'	19,072
Permanent differences	'	'	'	'	'	'	'	'	66	-196	-147
Other	'	'	'	'	'	'	'	'	'	'	-2
Prior year true-up	'	'	'	'	'	'	'	'	-409	-6,450	-829
Change in the balance of the valuation allowance for deferred tax assets allocated to income tax expense	'	'	'	'	'	'	'	'	19,597	15,190	-13,396
Income taxes	'	'	'	'	'	'	'	'	'	'	'

Significant_Components_of_Defe

Significant Components of Deferred Income Tax Expense (Benefit) (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Components Of Income Tax Expense [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Deferred tax (benefit) expense	'	'	'	'	'	'	'	'	($19,597)	($15,190)	$13,396
Federal deferred tax benefit relating to the exercise of stock options	'	'	'	'	'	'	'	'	'	'	'
Increase (decrease) in the valuation allowance for deferred tax asset	'	'	'	'	'	'	'	'	19,597	15,190	-13,396
Income taxes	'	'	'	'	'	'	'	'	'	'	'

Deferred_Tax_Assets_and_Deferr

Deferred Tax Assets and Deferred Tax Liabilities (Detail) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred tax assets (liabilities):	'	'
Net operating loss carryforwards	$149,510	$133,677
Non-cash compensation	7,022	6,478
Unrealized / realized loss on securities	1,164	1,164
Capitalized Inventory	3,061	'
Research and development	2,088	1,684
Intangible assets due to different amortization methods	-135	63
Accrued expenses	53	100
Other temporary differences	11	10
Deferred tax asset, excluding valuation allowance	162,774	143,176
Less valuation allowance	-162,774	-143,176
Net deferred tax assets	'	'

Components_of_Interest_and_Oth

Components of Interest and Other Income, Net (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Component Of Other Expense Income Nonoperating [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Interest income	'	'	'	'	'	'	'	'	$190	$52	$159
Other income	'	'	'	'	'	'	'	'	161	166	221
Compensatory damage award, net	'	'	'	'	'	'	'	'	'	1,501	'
Interest and other income, net	$71	$81	$96	$103	$50	$51	$1,556	$62	$351	$1,719	$380

Interest_and_Other_Income_Net_1

Interest and Other Income, Net - Additional Information (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2012
Component Of Other Expense Income Nonoperating [Line Items]	'
Compensatory damage award, net	$1,501

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2014	Dec. 31, 2013	Dec. 31, 2013
	sqft				Subsequent Event	Remaining	Research and Development Expense
Commitments and Contingencies [Line Items]	'	'	'	'	'	'	'
Contractual obligation	'	'	'	'	'	'	$19,921,000
Other Commitment	'	14,817,000	'	'	'	'	'
Additional square feet leased	6,800	'	'	'	'	'	'
Rental expense	'	667,000	537,000	538,000	'	'	'
Recognized sublet income	'	161,000	166,000	221,000	'	120,600	'
Operating leases, future minimum payments due	'	2,848,000	'	'	'	'	'
Maximum contingent milestone payments	'	7,000,000	'	'	'	'	'
Milestone payments	'	'	'	'	$2,000,000	'	'

Future_Research_and_Developmen

Future Research and Development Payment Obligations (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Contractual Obligation [Line Items]	'
2014	$19,629
2015	254
2016	$38

Future_Minimum_Lease_Commitmen

Future Minimum Lease Commitments (Detail) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Operating Leased Assets [Line Items]	'
2014	$949
2015	1,045
2016	$854

Litigation_Additional_Informat

Litigation - Additional Information (Detail) (USD $)	1 Months Ended
In Millions, unless otherwise specified	Jun. 30, 2012	7-May-12
Commitments Contingencies And Litigation [Line Items]	'	'
Loss contingency, damages awarded, value	'	$1.80
Proceeds from legal settlements	$1.50	'

Quarterly_Consolidated_Financi2

Quarterly Consolidated Financial Data (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenue:	'	'	'	'	'	'	'	'	'	'	'
License revenue	'	'	'	$7,000	'	'	'	'	$7,000	'	$5,000
Total revenue	'	'	'	7,000	'	'	'	'	7,000	'	5,000
Research and development:	'	'	'	'	'	'	'	'	'	'	'
Non-cash compensation	1,594	319	243	191	150	161	73	278	2,347	662	803
Other research and development	8,863	10,351	6,934	6,239	4,753	3,768	3,726	7,122	32,387	19,369	26,209
Total research and development	10,457	10,670	7,177	6,430	4,903	3,929	3,799	7,400	34,734	20,031	27,012
General and administrative:	'	'	'	'	'	'	'	'	'	'	'
Non-cash compensation	2,399	422	395	390	388	384	365	368	3,606	1,505	1,289
Other general and administrative	4,883	4,640	3,882	2,338	1,387	1,213	1,535	1,408	15,743	5,543	5,448
Total general and administrative	7,282	5,062	4,277	2,728	1,775	1,597	1,900	1,776	19,349	7,048	6,737
Total operating expenses	17,739	15,732	11,454	9,158	6,678	5,526	5,699	9,176	54,083	27,079	33,749
Operating loss	-17,739	-15,732	-11,454	-2,158	-6,678	-5,526	-5,699	-9,176	-47,083	-27,079	-28,749
Other income	'	'	'	'	'	'	'	'	'	'	'
Interest and other income, net	71	81	96	103	50	51	1,556	62	351	1,719	380
Loss before income taxes	-17,668	-15,651	-11,358	-2,055	-6,628	-5,475	-4,143	-9,114	-46,732	-25,360	-28,369
Income taxes	'	'	'	'	'	'	'	'	'	'	'
Loss before extraordinary gain	'	'	'	'	-6,628	-5,475	-4,143	-9,114	-46,732	-25,360	-28,123
Extraordinary gain	'	'	'	'	'	'	2,639	'	'	2,639	'
Net loss	($17,668)	($15,651)	($11,358)	($2,055)	($6,628)	($5,475)	($1,504)	($9,114)	($46,732)	($22,721)	($28,123)
Basic and diluted net loss per common share	'	'	'	'	'	'	'	'	'	'	'
Before extraordinary gain	'	'	'	'	($0.09)	($0.08)	($0.06)	($0.13)	'	'	'
Extraordinary gain	'	'	'	'	'	'	$0.04	'	'	$0.04	'
Basic and diluted net loss per common share	($0.21)	($0.19)	($0.14)	($0.03)	($0.09)	($0.08)	($0.02)	($0.13)	($0.58)	($0.32)	($0.42)

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (USD $)	1 Months Ended			12 Months Ended		1 Months Ended
	Jan. 31, 2013	Apr. 30, 2011	4-May-11	Dec. 31, 2013	Dec. 31, 2011	Feb. 28, 2014	Jan. 31, 2014	Jan. 30, 2013	Jan. 22, 2014
						Subsequent Event	Subsequent Event	Public offering	Public offering
									Subsequent Event
Subsequent Event [Line Items]	'	'	'	'	'	'	'	'	'
Shares issued in public offering	'	'	7,021,277	'	'	'	'	9,469,100	7,935,000
Share price	'	'	$4.70	'	'	'	'	$8.49	$14.50
Proceeds from public offering, gross	'	'	$33,000,000	'	'	'	'	$80,400,000	$115,100,000
Proceeds from public offering, net	'	'	30,700,000	74,753,000	30,734,000	'	'	74,753,000	107,600,000
Underwriting discounts and offering expenses	'	'	2,300,000	5,640,000	2,266,000	'	'	5,640,000	7,500,000
License agreements, non-refundable milestone payment received	7,000,000	5,000,000	'	'	'	10,000,000	'	'	'
License agreements, potential milestone receivable	'	'	'	'	'	$55,000,000	$55,000,000	'	'