Fair Value Measurements - Significant Assumptions Used in Valuation of Warrant Derivative Liability (Detail) (USD $)	9 Months Ended
Sep. 30, 2013
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Remaining Term of Warrants	5 years
Warrant Derivative Liability [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Exercise price	$ 1.63
Stock price	$ 2.89
Volatility	75.00%
Remaining Term of Warrants	1 year 4 months 28 days
Risk-free interest rate	0.20%

Fair Value Assumptions Stock Price

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- Definition

Agreed upon price for the exchange of the underlying asset.

+ 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 (e)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

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- Definition

Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Risk-free interest rate assumption used in valuing an instrument.

+ References

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- Definition

Weighted average expected volatility of stock price.

+ References

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