v2.4.0.6
Securitizations and Variable Interest Entities, Significant Continuing Involvement - Unconsolidated VIEs (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2012
Dec. 31, 2011
Variable Interest Entity [Line Items]    
Total VIE assets $ 1,527,749 $ 1,463,183
Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 1,207,348 1,135,629
Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 58,016 61,461
Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 175,045 179,007
Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 10,493 11,240
Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 9,676 9,757
Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 12,036 9,606
Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 19,717 19,257
Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 11,831 12,191
Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 6,155 6,318
Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Total VIE assets 17,432 18,717
Debt and equity interests [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 39,615 39,799
Maximum exposure to loss 39,615 39,799
Debt and equity interests [Member] | Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 4,418 4,682
Maximum exposure to loss 4,418 4,682
Debt and equity interests [Member] | Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 2,433 2,460
Maximum exposure to loss 2,433 2,460
Debt and equity interests [Member] | Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 7,033 7,063
Maximum exposure to loss 7,033 7,063
Debt and equity interests [Member] | Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 1,011 1,107
Maximum exposure to loss 1,011 1,107
Debt and equity interests [Member] | Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 9,429 9,511
Maximum exposure to loss 9,429 9,511
Debt and equity interests [Member] | Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 7,562 6,942
Maximum exposure to loss 7,562 6,942
Debt and equity interests [Member] | Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 4,113 4,119
Maximum exposure to loss 4,113 4,119
Debt and equity interests [Member] | Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 2,002 2,019
Maximum exposure to loss 2,002 2,019
Debt and equity interests [Member] | Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Debt and equity interests [Member] | Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 1,614 1,896
Maximum exposure to loss 1,614 1,896
Servicing assets [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 12,790 12,080
Maximum exposure to loss 12,790 12,080
Servicing assets [Member] | Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 11,922 11,070
Maximum exposure to loss 11,922 11,070
Servicing assets [Member] | Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 367 353
Maximum exposure to loss 367 353
Servicing assets [Member] | Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 469 623
Maximum exposure to loss 469 623
Servicing assets [Member] | Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Servicing assets [Member] | Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 32 34
Maximum exposure to loss 32 34
Variable Interest Entity Derivatives [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 232 643
Maximum exposure to loss 1,932 2,487
Variable Interest Entity Derivatives [Member] | Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Variable Interest Entity Derivatives [Member] | Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 1 1
Maximum exposure to loss 1 1
Variable Interest Entity Derivatives [Member] | Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 337 349
Maximum exposure to loss 519 538
Variable Interest Entity Derivatives [Member] | Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 45 193
Maximum exposure to loss 838 874
Variable Interest Entity Derivatives [Member] | Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Variable Interest Entity Derivatives [Member] | Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (142) (130)
Maximum exposure to loss 142 130
Variable Interest Entity Derivatives [Member] | Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Variable Interest Entity Derivatives [Member] | Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 8 40
Maximum exposure to loss 9 41
Variable Interest Entity Derivatives [Member] | Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Variable Interest Entity Derivatives [Member] | Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (17) 190
Maximum exposure to loss 423 903
Other commitments and guarantees [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (2,615) (2,463)
Maximum exposure to loss 6,613 6,170
Other commitments and guarantees [Member] | Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (1,087) (975)
Maximum exposure to loss 3,632 3,657
Other commitments and guarantees [Member] | Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (49) (48)
Maximum exposure to loss 327 295
Other commitments and guarantees [Member] | Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Other commitments and guarantees [Member] | Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Other commitments and guarantees [Member] | Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 0 0
Other commitments and guarantees [Member] | Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 1,944 1,504
Other commitments and guarantees [Member] | Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (1,399) (1,439)
Maximum exposure to loss 0 0
Other commitments and guarantees [Member] | Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 523 523
Other commitments and guarantees [Member] | Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 37 41
Other commitments and guarantees [Member] | Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) (80) (1)
Maximum exposure to loss 150 150
Net assets [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 50,022 50,059
Maximum exposure to loss 60,950 60,536
Net assets [Member] | Conforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 15,253 14,777
Maximum exposure to loss 19,972 19,409
Net assets [Member] | Other/Nonconforming Residential Mortgage Backed Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 2,752 2,766
Maximum exposure to loss 3,128 3,109
Net assets [Member] | Commercial mortgage securitizations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 7,839 8,035
Maximum exposure to loss 8,021 8,224
Net assets [Member] | Collateralized Debt Obligations Debt Securities [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 1,056 1,300
Maximum exposure to loss 1,849 1,981
Net assets [Member] | Collateralized Debt Obligations Loans [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 9,429 9,511
Maximum exposure to loss 9,429 9,511
Net assets [Member] | Asset-based finance structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 7,420 6,812
Maximum exposure to loss 9,648 8,576
Net assets [Member] | Tax Credit Structures [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 2,714 2,680
Maximum exposure to loss 4,113 4,119
Net assets [Member] | Collateralized loan obligations [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 2,010 2,059
Maximum exposure to loss 2,534 2,583
Net assets [Member] | Investment funds [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 0 0
Maximum exposure to loss 37 41
Net assets [Member] | Other securitizations and transactions [Member]
   
Variable Interest Entity [Line Items]    
Carrying value asset (liability) 1,549 2,119
Maximum exposure to loss $ 2,219 $ 2,983