Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
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Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2017 |
Sep. 30, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
| Share-based compensation expense | $ 709 | $ 787 | $ 2,071 | $ 2,329 |
| Related tax benefits on non-qualified stock options | $ 291 | $ 313 | ||
| Number of shares, stock options exercised (shares) | 10,625 | 2,375 | 22,125 | 42,584 |
| Stock option awards [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
| Related tax benefits on non-qualified stock options | $ 666 | |||
| Restricted stock awards [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
| Related tax benefits on non-qualified stock options | $ 182 | |||
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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 total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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