Common Stock - Summary of Stock Options Activity (Detail) - $ / shares |
6 Months Ended | |
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Jun. 30, 2016 |
Jun. 30, 2015 |
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
| Number of Optioned Common Shares, Beginning Balance | 1,479,221 | |
| Number of Optioned Common Shares, Granted | 1,635,250 | |
| Number of Optioned Common Shares, Expired | (16,520) | |
| Stock option exercises, shares | 0 | 0 |
| Number of Optioned Common Shares, Forfeited | (93,764) | |
| Number of Optioned Common Shares, Ending Balance | 3,004,187 | |
| Weighted Average Exercise Price, Beginning Balance | $ 8.78 | |
| Weighted Average Exercise Price, Granted | 0.86 | |
| Weighted Average Exercise Price, Expired | 7.25 | |
| Weighted Average Exercise Price, Forfeited | 5.08 | |
| Weighted Average Exercise Price, Ending Balance | $ 4.59 | |
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- References No definition available.
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- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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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://www.xbrl.org/2003/role/presentationRef
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
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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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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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