Acquisition and Discontinued Operations (Details 8) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Combined results of the discontinued operations
Net interest income	$ 538	$ 564	$ 1,091	$ 1,161
Provision for loan and lease losses			62	(47)
Net interest income (expense) after provision for loan and lease losses	517	572	1,028	1,209
Noninterest income	(485)	(454)	(957)	(911)
Noninterest expense	714	680	1,417	1,381
Income taxes	57	94	132	205
Income (loss) from discontinued operations, net of taxes	10	(9)	5	(20)
Segment, Discontinued Operations [Member]
Combined results of the discontinued operations
Net interest income	30	35	61	71
Provision for loan and lease losses	2	30	6	62
Net interest income (expense) after provision for loan and lease losses	28	5	55	9
Noninterest income	(2)	(11)	(20)	(20)
Noninterest expense	10	9	27	21
Income (loss) before income taxes	16	(15)	8	(32)
Income taxes	6	(6)	3	(12)
Income (loss) from discontinued operations, net of taxes	$ 10	$ (9)	$ 5	$ (20)