Income Taxes (Components of Income Tax Expense (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CurrentIncomeTaxExpenseBenefitContinuingOperationsAbstract
CurrentFederalTaxExpenseBenefit	$ 36,759	$ 26,637	$ 32,230
CurrentStateAndLocalTaxExpenseBenefit	0	0	0
Current Income Tax Expense (Benefit)	36,759	26,637	32,230
DeferredIncomeTaxExpenseBenefitContinuingOperationsAbstract
DeferredFederalIncomeTaxExpenseBenefit	295,613	196,997	(198,293)
DeferredStateAndLocalIncomeTaxExpenseBenefit	0	0	0
Deferred Income Tax Expense (Benefit)	295,613	196,997	(198,293)
Total income tax expense (benefit) on continuing operations	332,372	223,634	(166,063)
IncomeTaxEffectsAllocatedDirectlyToEquityAbstract
Other comprehensive income (loss)	(41,149)	(7,218)	(16,240)
AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensation	4,354	5,730	0
Total income taxes	$ 295,577	$ 222,146	$ (182,303)