Income Taxes - Schedule of Reconciliation of the U.S. Statutory Income Tax Rate to the Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
U.S. federal income tax rate	21.00%	35.00%	35.00%
State taxes, net of federal benefit	3.00%	1.90%	2.00%
Tax-exempt income	(2.10%)	(4.50%)	(6.10%)
Business tax credits	(6.90%)	(6.80%)	(13.60%)
Foreign tax differential	(0.60%)	(7.40%)	(7.70%)
Transition tax	0.00%	15.70%	0.00%
Deferred tax revaluation	(1.10%)	(6.80%)	0.00%
Foreign designated earnings	(0.00%)	(0.70%)	(6.80%)
Foreign capital transactions	(0.00%)	(0.00%)	(4.30%)
Litigation expense	0.30%	0.00%	1.40%
Other, net	(0.30%)	(1.50%)	(0.90%)
Effective tax rate	13.30%	24.90%	(1.00%)

Effective Income Tax Rate Reconciliation, Deduction, Foreign Capital Investment, Percent

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Effective Income Tax Rate Reconciliation, Litigation Expense, 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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Effective Income Tax Rate Reconciliation, Tax Cuts and Jobs Act of 2017, Transition Tax on Accumulated Foreign Earnings, 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 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 the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to deduction for extraterritorial income exclusion.

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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 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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