Income Taxes (Schedule Of Income Tax Expense/(Benefit)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Current Income Tax Expense (Benefit) [Abstract]
U.S. federal	$ 657	$ (605)	$ 13
Non-U.S.	52	93	80
U.S. state	19	(22)	(137)
Total current	728	(534)	(44)
Deferred Income Tax Expense (Benefit) [Abstract]
U.S. federal	1,209	1,856	969
Non-U.S.	(13)	(8)	(13)
U.S. state	83	68	284
Total deferred	1,279	1,916	1,240
Income Tax Expense (Benefit) [Abstract]
Total income tax expense	$ 2,007	$ 1,382	$ 1,196