Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Taxes [Line Items]
Income tax expense	$ 13,596	$ 11,644
Effective tax rate	25.30%	22.50%
Excess tax expense (benefits) from discrete items	$ 500
Effect of reporting discrete items during the period	1.00%
Unfavorable effect from income tax accrual adjustment relating to return to provision true ups		$ 1,800
Statutory Effective Tax Rate [Member]
Income Taxes [Line Items]
U.S. federal statutory rate	21.00%
State income tax rate, net of federal benefit	3.60%

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other deductions.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit allocated to Income or Loss from extraordinary items.

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Amount of increase (decrease) to previously recorded tax expense. Includes, but is not limited to, significant settlements of income tax disputes, and unusual tax positions or infrequent actions taken by the entity, including tax assessment reversal, and IRS tax settlement.

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Income taxes.

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