Income Taxes - Reconciliation of Pre-Tax Income (Detail)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory tax rate	21.00%	21.00%	35.00%
Foreign rate differential	4.00%		(5.00%)
State taxes, net of federal benefit	3.00%	3.00%	2.00%
Non-deductible expenses	1.00%	2.00%	2.00%
Reserves for uncertain tax positions	1.00%		(2.00%)
Credits and exemptions	(4.00%)	(2.00%)	(3.00%)
Outside basis differences recognized as a result of a legal entity restructuring	(20.00%)
Tax Reform		1.00%	12.00%
Change in valuation allowance		(1.00%)	(2.00%)
Acquisition-related costs		(2.00%)
Other	(1.00%)	1.00%	1.00%
Effective tax rate	5.00%	23.00%	40.00%

Effective income tax rate reconciliation acquisition related costs.

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Effective income tax rate reconciliation, restructuring benefits.

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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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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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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 income tax contingencies. Includes, but not limited to, domestic tax contingency, foreign tax contingency, state and local tax contingency, and other contingencies.

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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