Income Taxes (Details)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Reconciliation between the statutory United States Federal income tax rate and the Company's effective income tax rate
Statutory rate	35.00%	35.00%
State taxes	1.20%	0.90%
Domestic production activities deduction	(2.10%)	(2.20%)
Noncontrolling interest in partially-owned subsidiaries	(1.00%)	(1.20%)
Other, net	0.40%	0.10%
Effective rate	33.50%	32.60%

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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