v3.21.2
Derivatives and Hedging Activities - Credit Derivatives (Detail) - USD ($)
$ in Millions
Sep. 30, 2021
Dec. 31, 2020
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative $ 564,935 $ 515,850
Maximum Payout/Notional Amount of Purchased Credit Derivatives 612,880 558,180
Offsetting Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 481,820 442,907
Other Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 131,058 115,271
Less than 1 Year [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 120,722 104,728
1 - 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 366,078 362,791
Greater than 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 78,135 48,331
Written Credit Derivative [Member]    
Derivative [Line Items]    
Fair Value Asset of Written Credit Derivatives 12,118 11,314
Fair Value Liability of Written Credit Derivatives 4,090 4,619
Fair Value Net Asset/(Liability) of Written Credit Derivatives 8,028 6,695
0 - 250 [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 506,644 471,326
0 - 250 [Member] | Offsetting Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 440,512 407,315
0 - 250 [Member] | Other Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 108,898 103,604
0 - 250 [Member] | Less than 1 Year [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 105,584 96,049
0 - 250 [Member] | 1 - 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 332,858 331,145
0 - 250 [Member] | Greater than 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 68,202 44,132
0 - 250 [Member] | Written Credit Derivative [Member]    
Derivative [Line Items]    
Fair Value Asset of Written Credit Derivatives 10,165 10,302
Fair Value Liability of Written Credit Derivatives 894 1,112
Fair Value Net Asset/(Liability) of Written Credit Derivatives 9,271 9,190
251 - 500 [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 41,924 27,578
251 - 500 [Member] | Offsetting Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 28,582 19,822
251 - 500 [Member] | Other Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 19,072 7,272
251 - 500 [Member] | Less than 1 Year [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 10,289 5,826
251 - 500 [Member] | 1 - 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 24,819 17,913
251 - 500 [Member] | Greater than 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 6,816 3,839
251 - 500 [Member] | Written Credit Derivative [Member]    
Derivative [Line Items]    
Fair Value Asset of Written Credit Derivatives 1,430 638
Fair Value Liability of Written Credit Derivatives 991 1,119
Fair Value Net Asset/(Liability) of Written Credit Derivatives 439 (481)
501 - 1000 [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 8,149 9,523
501 - 1000 [Member] | Offsetting Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 6,350 8,679
501 - 1000 [Member] | Other Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 2,218 3,619
501 - 1000 [Member] | Less than 1 Year [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 807 450
501 - 1000 [Member] | 1 - 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 4,838 8,801
501 - 1000 [Member] | Greater than 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 2,504 272
501 - 1000 [Member] | Written Credit Derivative [Member]    
Derivative [Line Items]    
Fair Value Asset of Written Credit Derivatives 295 256
Fair Value Liability of Written Credit Derivatives 597 387
Fair Value Net Asset/(Liability) of Written Credit Derivatives (302) (131)
Greater than 1000 [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 8,218 7,423
Greater than 1000 [Member] | Offsetting Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 6,376 7,091
Greater than 1000 [Member] | Other Purchased Credit Derivatives [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Purchased Credit Derivatives 870 776
Greater than 1000 [Member] | Less than 1 Year [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 4,042 2,403
Greater than 1000 [Member] | 1 - 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 3,563 4,932
Greater than 1000 [Member] | Greater than 5 Years [Member]    
Derivative [Line Items]    
Maximum Payout/Notional Amount of Written Credit Derivative 613 88
Greater than 1000 [Member] | Written Credit Derivative [Member]    
Derivative [Line Items]    
Fair Value Asset of Written Credit Derivatives 228 118
Fair Value Liability of Written Credit Derivatives 1,608 2,001
Fair Value Net Asset/(Liability) of Written Credit Derivatives $ (1,380) $ (1,883)