Stockholders' Equity (Deficit) - Reconciliation of Warrant Liability Measured at Fair Value (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Equity [Abstract] | |||
| Beginning Balance | $ 3,961 | $ 23,421 | $ 32,558 |
| Initial fair value of common stock warrant related to February 2015 offering | 14,693 | ||
| Exercise of warrants | (17) | (10,116) | (11,462) |
| Change in common stock warrant value | (16,773) | (9,344) | 2,325 |
| Ending Balance | $ 1,864 | $ 3,961 | $ 23,421 |
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- References No definition available.
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Value of preferred stock and warrants for common stock issued. No definition available.
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