Income Taxes - Schedule of Reconciliation of Federal Statutory Rate to Company's Effective Tax Rate (Detail)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal income tax provision at statutory rate	21.00%	21.00%	21.00%
State income taxes, net of federal income tax benefit	0.60%	3.70%	(15.90%)
Foreign income tax rate differential	3.40%	2.00%	(18.90%)
Tax effect of tax credits	(10.20%)	8.20%	1.30%
Provision for (resolution of) tax matters	12.40%	(8.00%)	46.50%
Rate changes due to enacted legislation	0.70%	0.10%	7.20%
Effect of U.S. tax law change	(21.50%)		(7.50%)
Global Intangible Low-taxed Income	7.10%	(9.40%)	33.80%
Stock-based compensation	1.40%	(1.00%)	10.00%
Nondeductible officer's compensation	1.00%	(0.70%)	5.20%
Valuation allowance	11.70%	4.30%	15.70%
Pension termination, settlement and related	5.40%	5.00%
Other	2.80%	1.60%	7.80%
Actual tax rate	35.80%	26.80%	106.20%

Effective income tax rate reconciliation global intangible low-taxed income.

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Effective income tax rate reconciliation nondeductible officer's compensation.

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Effective income tax rate reconciliation pension termination, settlement and related.

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Effective income tax rate reconciliation provisional mandatory transition tax on accumulated foreign earnings due to Tax Cuts and Jobs Act of 2017.

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Effective income tax rate reconciliation tax credits and adjustments.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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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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