Income Taxes - Reconciliation of Statutory Federal Income Tax Rate (Details)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Statutory federal income tax rate	21.00%	35.00%	35.00%
State income taxes, net of federal effect	3.20%	2.30%	2.90%
Unconsolidated affiliate tax	0.10%	0.90%	4.20%
Tax expense (benefit) due to federal tax reform	1.20%	(20.30%)	0.00%
Excess tax benefit from share-based awards	(2.20%)	(3.60%)	0.00%
Sale of business	1.30%	0.00%	0.00%
Domestic production activities deduction	(0.00%)	(2.00%)	(3.00%)
Other, net	(0.30%)	(0.70%)	(0.50%)
Effective income tax rate	24.30%	11.60%	38.60%

Effective Income Tax Rate Reconciliation, Equity in Earnings (Losses) of Equity Method Investments

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Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Percent

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Effective Income Tax Reconciliation, Share-based Compensation, Excess Tax Benefit, 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 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 qualified production activity.

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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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