Share-Based Compensation - Additional Information (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | ||||
|---|---|---|---|---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
Jun. 30, 2019 |
Jun. 30, 2018 |
Mar. 31, 2019 |
Dec. 31, 2018 |
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| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||||
| Intrinsic value represents the excess of the closing stock price related to options outstanding (in usd per share) | $ 22.27 | $ 22.27 | $ 21.27 | $ 19.70 | ||
| Share-based compensation expense | $ 660,000 | $ 930,000 | $ 1,400,000 | $ 1,800,000 | ||
| Related tax benefits on non-qualified stock options | $ 198,000 | $ 262,000 | $ 411,000 | $ 512,000 | ||
| Number of shares, stock options exercised (shares) | 1,250 | 0 | 1,900 | 25,750 | ||
| Stock option awards | ||||||
| Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] | ||||||
| Unrecognized share-based compensation expense | $ 0 | $ 0 | ||||
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- Definition The excess of the closing stock price on the last day of the trading period over the exercise price. No definition available.
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. 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 cost not yet recognized for nonvested award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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