Stockholders' Equity - Outstanding Warrants to Purchase Shares of Common Stock (Detail) |
9 Months Ended |
|---|---|
|
Sep. 30, 2018
$ / shares
shares
| |
| Class Of Warrant Or Right [Line Items] | |
| Warrants Outstanding, December 31, 2017 | 3,331,735 |
| Issued | 190,000 |
| Exercised | 0 |
| Warrants Outstanding, September 30, 2018 | 3,521,735 |
| 2017 Private Placement Warrants | |
| Class Of Warrant Or Right [Line Items] | |
| Warrants Outstanding, December 31, 2017 | 2,954,462 |
| Issued | 0 |
| Exercised | 0 |
| Warrants Outstanding, September 30, 2018 | 2,954,462 |
| Weighted Average Exercise Price | $ / shares | $ 6.84 |
| 2017 Warrants | |
| Class Of Warrant Or Right [Line Items] | |
| Warrants Outstanding, December 31, 2017 | 377,273 |
| Issued | 0 |
| Exercised | 0 |
| Warrants Outstanding, September 30, 2018 | 377,273 |
| Weighted Average Exercise Price | $ / shares | $ 39.82 |
| 2018 Warrants | |
| Class Of Warrant Or Right [Line Items] | |
| Warrants Outstanding, December 31, 2017 | 0 |
| Issued | 190,000 |
| Exercised | 0 |
| Warrants Outstanding, September 30, 2018 | 190,000 |
| Weighted Average Exercise Price | $ / shares | $ 9.58 |
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- Definition Class of warrant or right exercised during period. No definition available.
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- Definition Class of warrant or right issued during period. No definition available.
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- Definition Exercise price per share or per unit of warrants or rights outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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