Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
3 Months Ended | 6 Months Ended | |
|---|---|---|---|
Jun. 30, 2017 |
Jun. 30, 2017 |
Dec. 31, 2016 |
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| Class Of Warrant Or Right [Line Items] | |||
| Warrants to purchase shares of common stock | 8.3 | 8.3 | |
| February 2015 Warrants | |||
| Class Of Warrant Or Right [Line Items] | |||
| Warrants to purchase shares of common stock | 8.3 | 8.3 | 8.3 |
| Warrant exercise price | $ 3.62 | $ 3.62 | $ 3.62 |
| February 2015 Warrants | Warrants | |||
| Class Of Warrant Or Right [Line Items] | |||
| Change in fair value of common stock warrants | $ (0.9) | $ (0.2) |
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- Definition Exercise price per share or per unit of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Number of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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