v3.10.0.1
Derivative Instruments and Hedging Activities (Maximum Potential Payout/Notional of Credit Protection Sold) (Details) - Credit Protection Sold - USD ($)
$ in Millions
Dec. 31, 2018
Dec. 31, 2017
Credit Derivatives    
Maximum potential payout/notional $ 224,145 $ 290,021
Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 42,347 88,228
1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 50,658 81,673
3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 102,231 94,110
Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 28,909 26,010
CDSs    
Credit Derivatives    
Maximum potential payout/notional 224,029 289,885
CDS protection sold with identical protection purchased 209,972 274,473
CDSs | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 42,347 88,226
CDSs | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 50,658 81,673
CDSs | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 102,231 94,110
CDSs | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 28,793 25,876
Single Name CDS    
Credit Derivatives    
Maximum potential payout/notional 104,563 146,948
Single Name CDS | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 32,432 53,934
Single Name CDS | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 34,937 58,884
Single Name CDS | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 28,489 24,350
Single Name CDS | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 8,705 9,780
Single Name CDS | Investment Grade    
Credit Derivatives    
Maximum potential payout/notional 73,486 109,341
Single Name CDS | Investment Grade | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 22,297 39,721
Single Name CDS | Investment Grade | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 23,876 42,591
Single Name CDS | Investment Grade | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 19,469 18,157
Single Name CDS | Investment Grade | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 7,844 8,872
Single Name CDS | Non-investment Grade    
Credit Derivatives    
Maximum potential payout/notional 31,077 37,607
Single Name CDS | Non-investment Grade | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 10,135 14,213
Single Name CDS | Non-investment Grade | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 11,061 16,293
Single Name CDS | Non-investment Grade | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 9,020 6,193
Single Name CDS | Non-investment Grade | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 861 908
Index and Basket CDS    
Credit Derivatives    
Maximum potential payout/notional 119,466 142,937
Index and Basket CDS | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 9,915 34,292
Index and Basket CDS | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 15,721 22,789
Index and Basket CDS | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 73,742 69,760
Index and Basket CDS | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 20,088 16,096
Index and Basket CDS | Investment Grade    
Credit Derivatives    
Maximum potential payout/notional 82,945 88,614
Index and Basket CDS | Investment Grade | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 5,341 29,046
Index and Basket CDS | Investment Grade | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 9,901 15,418
Index and Basket CDS | Investment Grade | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 60,887 37,343
Index and Basket CDS | Investment Grade | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 6,816 6,807
Index and Basket CDS | Non-investment Grade    
Credit Derivatives    
Maximum potential payout/notional 36,521 54,323
Index and Basket CDS | Non-investment Grade | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 4,574 5,246
Index and Basket CDS | Non-investment Grade | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 5,820 7,371
Index and Basket CDS | Non-investment Grade | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 12,855 32,417
Index and Basket CDS | Non-investment Grade | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 13,272 9,289
Other Credit Contracts    
Credit Derivatives    
Maximum potential payout/notional 116 136
Other Credit Contracts | Less Than 1 (Year)    
Credit Derivatives    
Maximum potential payout/notional 0 2
Other Credit Contracts | 1 - 3 (Years)    
Credit Derivatives    
Maximum potential payout/notional 0 0
Other Credit Contracts | 3 - 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional 0 0
Other Credit Contracts | Over 5 (Years)    
Credit Derivatives    
Maximum potential payout/notional $ 116 $ 134