Income Taxes - Schedule of Reconciliation of the U.S. Statutory Income Tax Rate to the Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	3.80%	3.40%	3.10%
Tax-exempt income	(1.30%)	(1.50%)	(2.00%)
Business tax credits	(5.10%)	(5.40%)	(4.10%)
Foreign tax differential	(0.80%)	(0.10%)	(0.60%)
Foreign legal entity restructuring	0.00%	(4.30%)	0.00%
Foreign tax credit (benefits)/ limitations	(0.90%)	2.20%	0.20%
Deferred tax revaluation	0.00%	0.00%	(1.00%)
Litigation expense	0.00%	1.60%	0.30%
Other, net	(0.20%)	0.40%	(0.60%)
Effective tax rate	16.50%	17.30%	16.30%

Effective Income Tax Rate Reconciliation, Litigation Expense, Percent

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Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Limitations, Percent

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Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Deferred Tax Asset, 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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 6.I.Fact.4)
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-Name Accounting Standards Codification
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
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-Section S99
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 6.I.Fact.4)
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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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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 (loss) exempt from income taxes.

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