Summary of Restricted Stock and Restricted Stock Unit Award Activity (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock unit awards that vested during the period	115,072
Fair value of restricted shares that vested during the period	$ 2,477	$ 8,700
Compensation expense recognized during the period	8,946	5,403
Income tax benefit (cost) related to restricted stock awards	$ 55	$ 2,620
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock unit awards that vested during the period	15,230	117,500
Fair value of restricted shares that vested during the period	$ 314	$ 3,634
Accumulated dividends paid upon vesting of restricted stock unit awards	62	563
Compensation expense recognized during the period	1,629	3,029
Income tax benefit (cost) related to restricted stock awards	$ (306)	$ 526

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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