Fair Value of Warrants - Summary of Derivative Warrant Activity (Detail) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
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| Class of Warrants Outstanding [Roll Forward] | ||
| Beginning balance | $ 178 | $ 248 |
| Fair value of warrants exchanged for stock | (10) | |
| Change in fair value of warrants | (167) | (70) |
| Ending balance | 1 | 178 |
| 2016 Offerings | ||
| Class of Warrants Outstanding [Roll Forward] | ||
| Beginning balance | 178 | 225 |
| Fair value of warrants exchanged for stock | (10) | |
| Change in fair value of warrants | (167) | (47) |
| Ending balance | 1 | 178 |
| 2017 Offerings | ||
| Class of Warrants Outstanding [Roll Forward] | ||
| Beginning balance | 0 | 23 |
| Fair value of warrants exchanged for stock | 0 | |
| Change in fair value of warrants | 0 | (23) |
| Ending balance | $ 0 | $ 0 |
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- Definition Change In Fair Value Of Warrant Liability No definition available.
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- Definition Class of Warrants Outstanding [Roll Forward] No definition available.
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- Definition Warrants and Rights, Exchanged No definition available.
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- Definition Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price. No definition available.
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- Details
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- Details
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