Share-based Compensation - Share-Based Compensation Expense and Related Tax Benefits (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||
| Share-based compensation expense | $ 2,893 | $ 3,008 | $ 2,241 |
| Related tax benefits | $ 1,179 | $ 1,191 | $ 755 |
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- References 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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