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Fair Value of Financial Instruments - Rollforward of Level 3 (Details) - Significant Unobservable Inputs (Level 3) - Warrant Liability - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 3,372	$ 6,371
Change in fair value of warrant liability included in earnings	(1,473)	(3,009)
Issuance of common stock on warrant exercise	0	(13)
Gain on settlement of warrants	0	(37)
Ending balance	$ 1,899	$ 3,312

X

- Definition

Warrant Liability, Reduction, Transferred to Equity

+ References

No definition available.

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X

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 820



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)(1)



-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 820



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)(2)



-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 820



-SubTopic 10



-Section 50



-Paragraph 2



-Subparagraph (c)



-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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