Common Stock - Summary of Stock Options Activity (Detail) - $ / shares |
6 Months Ended | |
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Jun. 30, 2019 |
Jun. 30, 2018 |
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
| Number of Optioned Common Shares, Beginning Balance | 665,585 | |
| Number of Optioned Common Shares, Granted | 345,350 | 0 |
| Number of Optioned Common Shares, Ending Balance | 1,010,935 | |
| Weighted Average Exercise Price, Beginning Balance | $ 15.65 | |
| Weighted Average Exercise Price, Granted | 1.73 | |
| Weighted Average Exercise Price, Ending Balance | $ 10.90 | |
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- References No definition available.
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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