Differentiation between Federal Statutory Tax Rate and Overall Effective Tax Rate (Detail)	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Income Tax Rate Reconciliation [Line Items]
Statutory provision	35.00%	35.00%	35.00%	35.00%
State taxes, net of federal benefit	1.20%	2.30%	1.60%	1.10%
City taxes	0.20%	0.10%	0.20%	0.10%
Foreign effective tax rates different from US statutory rate	(9.20%)	(14.40%)	(10.10%)	(13.00%)
Tax reserve				(1.50%)
Prior Year related state tax payment			0.60%
Valuation Reserve Adjustment			(1.80%)
Tax related to repatriation	(10.80%)	390.50%	(4.00%)	128.20%
Effective Income Tax Rate	16.40%	413.50%	21.50%	149.90%

Effective Income Tax Rate Reconciliation, City Income Taxes, Percent

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Income Tax Rate Reconciliation [Line Items]

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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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-Publisher FASB
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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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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 revisions of previously reported income tax expense.

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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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