Income Taxes - Reconciliation of the Federal Statutory Tax Rate to Total Provisions (Detail)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Taxes computed at statutory rate	21.00%	21.00%	21.00%	21.00%
State income taxes, net of federal income tax benefit	(3.36%)	3.16%	2.52%
Federal research credit	(0.79%)	(0.34%)	(0.14%)
Equity in losses of foreign joint venture	0.64%	0.19%	0.08%
Impairment on investment in foreign joint venture	11.20%
Tax loss on investment in foreign joint venture	(22.73%)
Foreign rate differential	1.15%		(0.07%)
Noncontrolling interests	(2.88%)	(1.18%)	(0.78%)
Tax Reform Act			0.18%
CARES Act NOL carryback	(5.77%)
Other, net	1.49%	0.27%	0.38%
Provision for income taxes	(0.06%)	23.10%	23.17%

Effective income tax rate reconciliation cares act net operating loss carryback.

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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 tax law, primarily the change in enacted tax rate.

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Effective income tax rate reconciliation equity in losses of foreign joint venture.

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Effective income tax rate reconciliation impairment on investment in foreign joint venture.

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Effective income tax rate reconciliation tax loss on investment in foreign joint venture.

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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 attributable to noncontrolling interest income (loss) exempt from income taxes.

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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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