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Fair Value Measurements - Additional Information (Detail) (USD $)
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9 Months Ended | |
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Sep. 30, 2013
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Dec. 31, 2012
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| Fair Value Disclosures [Abstract] | ||
| Warrant liability | $ 548,000 | $ 3,422,000 |
| Maximum maturity period of cash and cash equivalents | 90 days | |
| Maximum maturity period of short-term investments | 1 year | |
| Other than temporary impairments to investment in marketable securities | $ 0 |
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- Definition
Maximum maturity period of cash and cash equivalents. No definition available.
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- Definition
Maximum maturity period of short term investments. No definition available.
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- Details
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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
This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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