Common Stock - Summary of Stock Options Activity (Detail) |
12 Months Ended |
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Dec. 31, 2018
$ / shares
shares
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
| Number of Optioned Common Shares, Beginning Balance | shares | 111,578 |
| Number of Optioned Common Shares, Granted | shares | 554,400 |
| Number of Optioned Common Shares, Forfeited | shares | (393) |
| Number of Optioned Common Shares, Ending Balance | shares | 665,585 |
| Weighted Average Exercise Price, Beginning Balance | $ / shares | $ 80.01 |
| Weighted Average Exercise Price, Granted | $ / shares | 2.81 |
| Weighted Average Exercise Price, Forfeited | $ / shares | 160.79 |
| Weighted Average Exercise Price, Ending Balance | $ / shares | $ 15.65 |
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- References No definition available.
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- Definition The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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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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