Income Taxes - Components of the Company's Income Tax Expense (Benefit) (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current taxes:
Federal	$ 26,247	$ 23,700	$ 39,569
State	7,288	7,083	5,914
Deferred taxes	1,148	3,155	4,383
Total income taxes	$ 34,683	$ 33,938	$ 49,866

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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