Cash Proceeds Along with Fair Value Disclosures Related to Grants, Exercises, and Vested Options (Detail) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | |
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Mar. 31, 2018 |
Mar. 31, 2017 |
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | ||
| Proceeds from stock options exercised | $ 2 | |
| Weighted-average fair value of options granted during period | $ 0.29 | $ 1.05 |
| Total fair value of shares vested during the period | $ 520 | $ 334 |
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- References No definition available.
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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