Investment Securities (Gains And Losses Related To Investment Securities) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Investments, Debt and Equity Securities [Abstract]
Gross realized gains from sales of available-for-sale securities	$ 32		$ 62		$ 51		$ 66
Gross realized losses from sales of available-for-sale securities	(46)	[1]	0	[1]	(46)	[1]	0	[1]
Gross losses from other-than-temporary impairment	(21)		(44)		(46)		(79)
Losses not related to credit	8		9		25		33
Gains (Losses) related to investment securities, net	(27)		27		(16)		20
Impairment associated with expected credit losses	(9)		(24)		(13)		(29)
Impairment Associated With Management's Intent To Sell The Impaired Securities Prior To Their Recovery In Value	0		(8)		0		(8)
Impairment associated with adverse changes in timing of expected future cash flows	4		3		8		9
Net impairment losses	$ (13)		$ (35)		$ (21)		$ (46)

[1] Loss resulted from the sale of all of our Greek securities, which were previously classified as held to maturity. The sale was undertaken as a result of the effect of significant deterioration in the creditworthiness of the underlying collateral, including significant downgrades of the securities' published credit ratings.