Investment Securities (Details 3) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Mar. 31, 2011 Scenario, Previously Reported [Member]
Accretable balance of the structured investment securities and other investment securities
Balance at beginning of period	$ 104		$ 100	$ 139	$ 126
Accretion	(4)	(4)	(8)	(9)
Other (a)	(7)	(5)	1	(13)
Balance at end of period	$ 93	$ 117	$ 93	$ 117	$ 126