Stock Based Compensation - Summary of Activity Related to PSUs (Detail) - $ / shares |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| PSUs granted | 0 | 0 | 0 |
| Performance Shares [Member] | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Number of Options, Outstanding | 1,153,617 | ||
| PSUs granted | 0 | ||
| PSUs forfeited | (111,960) | ||
| PSUs vested | (90,000) | ||
| Number of Options, Outstanding | 951,657 | 1,153,617 | |
| Weighted Average Grant Date Fair Value, Outstanding | $ 3.66 | ||
| Weighted Average Grant Date Fair Value, PSUs granted | 0 | ||
| Weighted Average Grant Date Fair Value, PSUs forfeited | 2.62 | ||
| Weighted Average Grant Date Fair Value, PSUs vested | 13.82 | ||
| Weighted Average Grant Date Fair Value, Outstanding | $ 2.65 | $ 3.66 | |
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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 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 The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 grant-date fair value of non-vested options forfeited. No definition available.
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- Definition Weighted average grant-date fair value of non-vested options outstanding. No definition available.
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- Definition Number of options vested. No definition available.
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- Definition Weighted average grant-date fair value of options vested. No definition available.
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- Details
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