Investment Securities (Summary of OTTI Credit Losses Recognized in Earnings) (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
OTTI credit losses recognized in earnings	$ (39)	$ (94)	$ (73)	$ (210)
Residential Mortgage-backed Non-agency [Member]
OTTI credit losses recognized in earnings	(35)	(81)	(63)	(154)
Asset backed [Member]
OTTI credit losses recognized in earnings	(4)	(10)	(9)	(53)
Other Debt Securities [Member]
OTTI credit losses recognized in earnings			(1)
Non Agency Commercial Mbs [Member]
OTTI credit losses recognized in earnings		$ (3)		$ (3)