Income Taxes - Provision for Income Tax (Benefit) Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Current:
Federal	$ 84,213	$ (64)
State	160	(170)
Total	84,373	(234)
Deferred:
Federal	12,045	211
State	10,487	23
Total	22,532	234
Income tax expense	$ 106,905	$ 0

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations.