Loans and Allowance for Loan Losses (Details 9) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
FICO scores:
720 and above	$ 18,078	$ 17,086
720 and above, in percent	76.00%	75.00%
Below 720	5,198	5,363
Below 720, in percent	22.00%	24.00%
No FICO available	406	316
No FICO available, in percent	2.00%	1.00%
Total FICO scores	23,682	22,765
Total FICO scores, in percent	100.00%	100.00%
LTV Ratios:
Less than 80 percent	17,056	14,492
Less than 80 percent, in percent	72.00%	64.00%
80-100	3,968	5,027
80-100 percent	17.00%	22.00%
Greater than 100 percent	2,239	2,821
Greater than 100 percent, in percent	10.00%	12.00%
No LTV available	331	330
No LTV available, in percent	1.00%	2.00%
Total LTV Ratios	23,594	22,670
Total LTV Ratios, in percent	100.00%	100.00%
Residential Mortgage [Member]
FICO scores:
720 and above	15,633	14,553
Below 720	4,190	4,319
No FICO available	337	247
Total FICO scores	20,160	19,119
LTV Ratios:
Less than 80 percent	15,160	12,464
80-100	3,331	4,415
Greater than 100 percent	1,603	2,146
No LTV available	66	94
Total LTV Ratios	20,160	19,119
Home Equity and Other Consumer Loans [Member]
FICO scores:
720 and above	2,445	2,533
Below 720	1,008	1,044
No FICO available	69	69
Total FICO scores	3,522	3,646
Home Equity Loans [Member]
LTV Ratios:
Less than 80 percent	1,896	2,028
80-100	637	612
Greater than 100 percent	636	675
No LTV available	265	236
Total LTV Ratios	$ 3,434	$ 3,551