MidCap Secured Loan Facility - Schedule of Fair Value of Warrants Based Upon the Black Scholes Valuation Model Assumptions (Detail) (USD $)	12 Months Ended
Dec. 31, 2014
Debt Disclosure [Abstract]
Market price of stock	$ 4.41us-gaap_SharePrice
Term of warrant	5 years
Volatility	81.05%
Risk free interest rate	2.90%

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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

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=36462937&loc=d3e19207-110258

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- Definition

Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

+ References

+ Details

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- Definition

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

+ References

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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