Income Taxes (Components of Income Tax Expense (Benefit)) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract]
Total income tax expense (benefit) on continuing operations	$ 114,416	$ (139,531)	$ 222,250	$ 37,976
Income Tax Effects Allocated Directly to Equity [Abstract]
Other comprehensive income (loss)	$ (83,977)	$ 18,822	$ (96,656)	$ 17,335