Share-based Compensation - Summary of Information under Plans (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Proceeds from exercise of stock options | $ 570 | $ 288 | $ 1,453 |
| 2007 and 2013 Plan | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Fair value of options vested | 184 | 820 | 2,322 |
| Total intrinsic value of options exercised | 0 | 432 | 1,862 |
| Proceeds from exercise of stock options | $ 0 | $ 288 | $ 1,453 |
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- Definition Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. 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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- Details
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