Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:
Federal									$ (81,784)	$ (3,493)	$ (310)
State									10,537	8,395	15,140
Total current									(71,247)	4,902	14,830
Deferred:
Federal									279,973	200,322	159,566
State									21,865	28,280	16,626
Total deferred									301,838	228,602	176,192
Total income tax expense									230,591	233,504	191,022
Less: income tax expense (benefit) on discontinued operations										(3,813)	7,418
Income tax expense - continuing operations	$ 9,167	$ 131,912	$ 77,043	$ 12,469	$ 18,157	$ 147,116	$ 76,689	$ (4,645)	$ 230,591	$ 237,317	$ 183,604