Reconciliation between Federal Statutory Rate and Effective 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%
State taxes, net of federal income tax benefit	2.60%	2.20%	2.40%
Tax effects of foreign operations	(0.50%)	(1.20%)	(0.80%)
Tax benefit from settlement of employee equity awards	(0.10%)	(1.90%)	(0.00%)
Enactment of the TCJA-17	(0.60%)	(1.70%)	(0.00%)
Other items	0.90%	0.20%	0.20%
Impact of income attributable to noncontrolling interests	(0.40%)	(0.60%)	(1.40%)
Effective tax rate	22.90%	32.00%	35.40%

Effective income tax rate reconciliation enactment of tax cuts and jobs act of two thousand seveen teen.

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Effective income tax rate reconciliation impact of income attributable to noncontrolling interest.

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Effective income tax rate reconciliation tax benefit from settlement of employee equity awards.

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

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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 state and local income tax expense (benefit), net of federal tax expense (benefit).

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