Business Segment Information (Business Segment Financial Results) (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
Net interest income (expense) (FTE)			$ 879		$ 788
Provision for credit losses	19	45	41		91
Noninterest income	211	202	417		409
Noninterest expenses	433	411	882		829
Provision (benefit) for income taxes			99		78
Net income (loss)	144	96	274		199
Net credit-related charge-offs			90		191
Assets, average	61,782	54,148	61,782		54,148
Loans, average			42,749		39,361
Deposits, average			48,495		41,041
Return on average assets			0.89%	[1]	0.73%	[1]
Efficiency ratio			68.62%		69.55%
Business Bank [Member]
Net interest income (expense) (FTE)			764		682
Provision for credit losses			14		17
Noninterest income			164		156
Noninterest expenses			309		323
Provision (benefit) for income taxes			188		155
Net income (loss)			417		343
Net credit-related charge-offs			54		126
Assets, average	33,780	29,991	33,780		29,991
Loans, average			32,844		29,528
Deposits, average			24,070		20,241
Return on average assets			2.47%	[1]	2.29%	[1]
Efficiency ratio			33.35%		38.45%
Retail Bank [Member]
Net interest income (expense) (FTE)			327		282
Provision for credit losses			7		47
Noninterest income			90		87
Noninterest expenses			361		325
Provision (benefit) for income taxes			16		2
Net income (loss)			33		(5)
Net credit-related charge-offs			21		46
Assets, average	6,060	5,507	6,060		5,507
Loans, average			5,356		5,053
Deposits, average			20,449		17,549
Return on average assets			0.31%	[1]	(0.06%)	[1]
Efficiency ratio			86.52%		87.94%
Wealth Management [Member]
Net interest income (expense) (FTE)			93		92
Provision for credit losses			16		23
Noninterest income			131		128
Noninterest expenses			159		155
Provision (benefit) for income taxes			18		16
Net income (loss)			31		26
Net credit-related charge-offs			15		19
Assets, average	4,620	4,769	4,620		4,769
Loans, average			4,549		4,780
Deposits, average			3,626		2,889
Return on average assets			1.36%	[1]	1.08%	[1]
Efficiency ratio			74.55%		72.89%
Finance [Member]
Net interest income (expense) (FTE)			(323)		(283)
Provision for credit losses			0		0
Noninterest income			30		31
Noninterest expenses			6		6
Provision (benefit) for income taxes			(111)		(96)
Net income (loss)			(188)		(162)
Net credit-related charge-offs			0		0
Assets, average	12,024	9,405	12,024		9,405
Loans, average			0		0
Deposits, average			169		244
Other [Member]
Net interest income (expense) (FTE)			18		15
Provision for credit losses			4		4
Noninterest income			2		7
Noninterest expenses			47		20
Provision (benefit) for income taxes			(12)		1
Net income (loss)			(19)		(3)
Net credit-related charge-offs			0		0
Assets, average	5,298	4,476	5,298		4,476
Loans, average			0		0
Deposits, average			$ 181		$ 118

[1] Return on average assets is calculated based on the greater of average assets or average liabilities and attributed equity.