Income Taxes (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Reconciliation between the statutory United States Federal income tax rate and the Company's effective income tax rate
Statutory rate	35.00%	35.00%	35.00%	35.00%
State taxes	0.90%	2.10%	0.90%	2.10%
Domestic production activities deduction	(2.20%)	(1.50%)	(2.20%)	(1.00%)
Noncontrolling interest in partially-owned subsidiaries	(1.10%)	(1.60%)	(1.20%)	(0.80%)
Tax assessments and settlements	0.00%	1.20%	0.00%	0.60%
Other, net	0.00%	(0.60%)	0.10%	(0.50%)
Effective rate	32.60%	34.60%	32.60%	35.40%