Income Taxes - Difference of Income Taxes from Statutory Federal Income Tax Rates (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal U.S. income tax rate	21.00%	35.00%	35.00%
State income taxes, net of federal tax benefit	4.70%	3.70%	4.20%
Permanent book/tax differences	0.60%	0.40%	0.50%
Non-U.S. income taxed at different rates, net of foreign tax credits	2.00%	(0.00%)	(0.60%)
Federal tax credits	(1.70%)	(1.30%)	(0.80%)
Tax impact of uncertain tax positions	0.80%	0.20%	0.00%
Valuation allowance release, net	0.00%	0.00%	(0.10%)
Tax effects of TCJA	0.40%	6.50%	0.00%
Other, net	(1.20%)	(0.60%)	(0.20%)
Effective tax rate	26.60%	43.90%	38.00%

Effective Income Tax Rate Reconciliation, Nondeductible Expense, Permanent Difference, Percent

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Effective income tax rate reconciliation tax impact of uncertain tax position

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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 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.

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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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