|
Common Stock - Summary of Outstanding Warrants (Detail) (USD $)
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9 Months Ended |
|---|---|
|
Sep. 30, 2014
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|
Series A Warrants [Member]
|
|
| Class of Warrant or Right [Line Items] | |
| Total Outstanding and Exercisable | 2,779,933 |
| Exercise price per Share | $ 4.00 |
| Expiration Date | 2019-07 |
|
Series B Warrants [Member]
|
|
| Class of Warrant or Right [Line Items] | |
| Total Outstanding and Exercisable | 670,269 |
| Exercise price per Share | $ 4.00 |
| Expiration Date | 2019-07 |
|
Stock warrants [Member]
|
|
| Class of Warrant or Right [Line Items] | |
| Total Outstanding and Exercisable | 1,587,301 |
| Exercise price per Share | $ 20.00 |
| Expiration Date | 2015-10 |
|
Pre-Funded Series B Warrants [Member]
|
|
| Class of Warrant or Right [Line Items] | |
| Total Outstanding and Exercisable | 1,340,538 |
| Exercise price per Share | $ 0.01 |
| Expiration Date | 2019-07 |