Loans and Allowance for Credit Losses (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Commercial
Commercial	$ 55,848	$ 50,734
Commercial, Percentage	25.90%	24.20%
Lease financing	5,686	5,914
Lease financing, Percentage	2.60%	2.80%
Total commercial	61,534	56,648
Total commercial, Percentage	28.50%	27.00%
Commercial Real Estate
Commercial mortgages	30,730	29,664
Commercial mortgages, Percentage	14.20%	14.10%
Construction and development	5,827	6,187
Construction and development, Percentage	2.70%	3.00%
Total commercial real estate	36,557	35,851
Total commercial real estate, Percentage	16.90%	17.10%
Residential Mortgages
Residential mortgages	30,463	28,669
Residential mortgages, Percentage	14.10%	13.70%
Home equity loans, first liens	9,457	8,413
Home equity loans, first liens, Percentage	4.40%	4.00%
Total residential mortgages	39,920	37,082
Total residential mortgages, Percentage	18.50%	17.70%
Credit card	16,905	17,360
Credit card, Percentage	7.80%	8.30%
Other Retail
Retail leasing	5,192	5,118
Retail leasing, Percentage	2.40%	2.40%
Home equity and second mortgages	17,476	18,131
Home equity and second mortgages, Percentage	8.10%	8.60%
Revolving credit	3,298	3,344
Revolving Credit, Percentage	1.50%	1.60%
Installment	5,437	5,348
Installment, Percentage	2.50%	2.60%
Automobile	12,103	11,508
Automobile, Percentage	5.60%	5.50%
Student	4,529	4,658
Student, Percentage	2.10%	2.20%
Total other retail	48,035	48,107
Total other retail, Percentage	22.20%	22.90%
Total loans, excluding covered loans	202,951	195,048
Total loans, excluding covered loans, Percentage	93.90%	93.00%
Covered loans	13,137	14,787
Covered loans, Percentage	6.10%	7.00%
Total loans	$ 216,088	$ 209,835
Total loans, Percentage	100.00%	100.00%