Cash Proceeds Along with Fair Value Disclosures Related to Grants, Exercises, and Vesting Options (Detail) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |||
| Proceeds from stock options exercised | $ 4 | $ 2 | |
| Weighted-average fair value of options granted per share | $ 0.29 | $ 1.51 | $ 1.38 |
| Total fair value of shares vested during the year | $ 227 | $ 587 | $ 1,191 |
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- References No definition available.
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- Definition Amount of cash inflow from exercise of option under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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