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Debt - Healthcare Royalty Financing Agreement Narrative (Details) (USD $)	0 Months Ended			3 Months Ended				12 Months Ended			0 Months Ended
	May 16, 2014	Jul. 27, 2012	Jul. 18, 2011	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jul. 18, 2011
Debt Instrument [Line Items]
Long-term debt interest expense								$ 2,750,000us-gaap_InterestExpenseDebt	$ 5,672,000us-gaap_InterestExpenseDebt	$ 6,708,000us-gaap_InterestExpenseDebt
Common stock issued and sold to Healthcare Royalty, amount				153,000us-gaap_CommonStockValue				153,000us-gaap_CommonStockValue	139,000us-gaap_CommonStockValue
Common stock issued and sold to Healthcare Royalty, shares				153,362,000us-gaap_CommonStockSharesIssued				153,362,000us-gaap_CommonStockSharesIssued	138,927,000us-gaap_CommonStockSharesIssued
Warrant exercisable to Healthcare Royalty, shares			225,000
Warrant exercisable to Healthcare Royalty, (usd per share)			$ 9.00invest_InvestmentWarrantsExercisePrice
Period For Warrant Term		5 years	10 years
Change in fair value of embedded derivatives								(14,000)	759,000	(147,000)
Loss on extinguishment of debt	1,254,000			0	0	(1,254,000)	0	(1,254,000)	0	0
Embedded Derivative Liabilities [Member]
Debt Instrument [Line Items]
Fair value of embedded derivatives	247,000			233,000				233,000
Healthcare Royalty Financing Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, outstanding			30,000,000								30,000,000
Common stock issued and sold to Healthcare Royalty, amount			1,500,000								1,500,000
Common stock issued and sold to Healthcare Royalty, shares			388,601								388,601
Common stock issued and sold to Healthcare Royalty, (usd per share)			$ 3.86								3.86
Net product sales amount received			10,000,000
Number of fixed payments			3
Fixed payment for Jan 31, 2015			10,000,000								10,000,000
Fixed payment for Jan 31, 2016				10,000,000				10,000,000
Fixed payment for Jan 31, 2017				10,000,000				10,000,000
Borrowed internal rate of return	17.00%
Repayments of Debt	40,041,000
Aggregate net proceed from financing agreement			29,485,000
Financing discounts			476,000								476,000
Healthcare Royalty Financing Agreement [Member] \| Embedded Derivative Liabilities [Member]
Debt Instrument [Line Items]
Financing discounts			605,000								605,000
Healthcare Royalty Financing Agreement [Member] \| Common Stock Warrant Liabilities [Member]
Debt Instrument [Line Items]
Change in fair value								378,000	(307,000)
Financing discounts			790,000								790,000
Healthcare Royalty Financing Agreement [Member] \| Scenario 1 [Member]
Debt Instrument [Line Items]
Net product sales amount received			75,000,000
Terminate payment base amount								52,500,000
Borrowed internal rate of return								19.00%
Healthcare Royalty Financing Agreement [Member] \| Scenario 1 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Revenue interest rate											5.00%
Healthcare Royalty Financing Agreement [Member] \| Scenario 1 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Revenue interest rate											5.75%
Healthcare Royalty Financing Agreement [Member] \| Scenario 2 [Member]
Debt Instrument [Line Items]
Revenue interest rate											2.50%
Net product sales amount received			75,000,000
Healthcare Royalty Financing Agreement [Member] \| Scenario 3 [Member]
Debt Instrument [Line Items]
Revenue interest rate											0.50%
Net product sales amount received			$ 150,000,000