Income Taxes - Reconciliation between the statutory U.S. Federal income tax rate and the Company's effective income tax rate	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Statutory rate	35.00%	35.00%	35.00%
Effect of Tax Cuts and Jobs Act	(128.00%)	(0.00%)	(0.00%)
State taxes	1.30%	1.40%	1.20%
Domestic production activities deduction	(0.00%)	(0.00%)	(1.40%)
Noncontrolling interest in partially-owned subsidiaries	(1.00%)	(1.30%)	(0.80%)
Settlements with tax authorities	(1.10%)	(0.10%)	(0.00%)
Equity compensation	0.50%	0.00%	0.00%
Changes in valuation allowances and reserves	1.80%	0.30%	0.00%
Other, net	(0.30%)	0.40%	0.00%
Effective rate	(91.80%)	35.70%	34.00%

Effective Income Tax Reconciliation, Equity Compensation

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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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-Publisher FASB
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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 attributable to noncontrolling interest income (loss) exempt from income taxes.

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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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