Loans - Consumer Loans excluding Credit Card, Delinquency (Details 6a) (USD $) In Millions, unless otherwise specified	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	$ 692,944	$ 685,498	$ 687,049
Residential real estate, excluding PCI [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	164,553	174,211
Percentage of Loans 30 Plus Days Past Due To Total Retained Loans	5.15%	5.88%
Residential real estate, excluding PCI [Member] | Current and less than 30 days past due and still accruing [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	145,620	153,630
Residential real estate, excluding PCI [Member] | 150 or More Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	13,077	13,423
Residential real estate, excluding PCI [Member] | Past Due And Still Accruing 90 Days Or More Member
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Residential real estate, excluding PCI [Member] | Nonaccrual [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	6,878	7,793
Residential real estate, excluding PCI [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	5,856	7,158
Residential real estate, excluding PCI [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	9,505	9,417
Current and less than 30 days past due and still accruing [Member] | Home Equity Senior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	21,621	23,615
150 or More Days Past Due [Member] | Home Equity Senior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	356	347
Past Due And Still Accruing 90 Days Or More Member | Home Equity Senior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Nonaccrual [Member] | Home Equity Senior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	479	479
Home Equity Senior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	22,364	24,376
Percentage of Loans 30 Plus Days Past Due To Total Retained Loans	3.32%	3.12%
Home Equity Senior Lien [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	387	414
Home Equity Senior Lien [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Home Equity Junior Lien [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	57,914	64,009
Percentage of Loans 30 Plus Days Past Due To Total Retained Loans	2.65%	2.65%
Home Equity Junior Lien [Member] | Current and less than 30 days past due and still accruing [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	56,379	62,315
Home Equity Junior Lien [Member] | 150 or More Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	214	186
Home Equity Junior Lien [Member] | Past Due And Still Accruing 90 Days Or More Member
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Home Equity Junior Lien [Member] | Nonaccrual [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	811	784
Home Equity Junior Lien [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	1,321	1,508
Home Equity Junior Lien [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Current and less than 30 days past due and still accruing [Member] | Prime Mortgages, including option ARMs [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	59,772	59,223
150 or More Days Past Due [Member] | Prime Mortgages, including option ARMs [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	11,154	11,264
Past Due And Still Accruing 90 Days Or More Member | Prime Mortgages, including option ARMs [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Nonaccrual [Member] | Prime Mortgages, including option ARMs [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	3,656	4,320
Prime Mortgages, including option ARMs [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	74,230	74,539
Percentage of Loans 30 Plus Days Past Due To Total Retained Loans	5.39%	6.68%
Prime Mortgages, including option ARMs [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	3,304	4,052
Prime Mortgages, including option ARMs [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	9,505	9,417
Current and less than 30 days past due and still accruing [Member] | Subprime Mortgage [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	7,848	8,477
150 or More Days Past Due [Member] | Subprime Mortgage [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	1,353	1,626
Past Due And Still Accruing 90 Days Or More Member | Subprime Mortgage [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Nonaccrual [Member] | Subprime Mortgage [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	1,932	2,210
Subprime Mortgage [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	10,045	11,287
Percentage of Loans 30 Plus Days Past Due To Total Retained Loans	21.87%	24.90%
Subprime Mortgage [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	844	1,184
Subprime Mortgage [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	0	0
Current and less than 30 days past due and still accruing [Member] | Mortgage Loans Insured by US Government Agencies [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	3,100	2,500
150 or More Days Past Due [Member] | Mortgage Loans Insured by US Government Agencies [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	8,400	7,900
Mortgage Loans Insured by US Government Agencies [Member] | 30 - 149 Days Past Due [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	2,100	2,500
Nonaccrual [Member] | Past Due 90 Days Or More And Government Guaranteed [Member]
Consumer Loans Excluding Credit Card Portfolio Segment, by Class, by Delinquency [Line Items]
Retained loans	$ 5,900	$ 2,800