Income Taxes - Reconciliation of Income Taxes Based on U.S. Federal Statutory Rate (Detail)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S federal statutory income tax rate	21.00%	21.00%	21.00%
Change in valuation allowance, exclusive of state	(1.30%)	1.80%	(1.10%)
State taxes, net of federal taxes, exclusive of tax reform	0.20%	(13.60%)	0.10%
Non-U.S. earnings taxed at different rates	1.40%	3.00%	0.30%
GILTI	(0.10%)	0.00%	0.00%
Goodwill impairment	(12.70%)	0.00%	(17.70%)
Nondeductible asset loss	0.00%	(2.20%)	(0.20%)
Research and development tax credit	0.40%	2.20%	0.30%
Change in uncertain tax positions	2.20%	4.30%	0.50%
Impact of tax reform:
Toll charge, net of foreign tax credit	0.00%	0.00%	0.70%
Remeasurement of deferred taxes pursuant to tax reform	0.00%	0.00%	(1.20%)
Impact of 2019 Treasury regulations	0.00%	(18.40%)	0.00%
CARES Act	2.70%	0.00%	0.00%
Divestiture of business segment, exclusive of tax reform	0.00%	0.00%	(1.10%)
Return to provision	(0.50%)	(0.20%)	(1.00%)
Taxes on unremitted foreign earnings	(3.90%)	(2.20%)	0.00%
Restructuring gain	(2.60%)	0.00%	0.00%
Other adjustments, net	(0.90%)	3.30%	0.10%
Effective tax rate	5.90%	(1.00%)	0.70%

Effective Income Tax Rate Reconciliation, CARES Act

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Effective Income Tax Rate Reconciliation, Global Intangible Low-Taxed Income, Percent

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Effective income tax rate reconciliation, impact of tax reform percent.

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Effective Income Tax Rate Reconciliation, Impact of Treasury Regulations, Percent

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Effective Income Tax Rate Reconciliation, Return to Provision

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Effective income tax rate reconciliation, toll charge, net of foreign tax credit, 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 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 attributable to disposition of a business not qualifying as a discontinued operation.

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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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