Income Taxes - Reconciliation Of Federal Statutory Rate To Effective Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	35.00%	35.00%
Increases (decreases) in the rate resulting from:
State income taxes, net of federal income tax impact	1.40%	4.30%	3.70%
Foreign income taxes	(0.10%)	(8.20%)	(4.30%)
Valuation allowance	(0.50%)	(1.90%)	0.50%
Tax Reform and other prior period adjustments	0.40%	(60.20%)	0.00%
Goodwill and intangible asset impairment charges	(14.00%)	0.00%	0.00%
Other	(1.30%)	4.40%	2.10%
Effective income tax rate	6.90%	(26.60%)	37.00%

Effective Income Tax Rate Reconciliation, Increases (Decrease) [Abstract]

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Effective Income Tax Rate Reconciliation,Tax Cuts and Jobs Act of 2017, Percent

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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 changes in the valuation allowance for deferred tax assets.

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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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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