v3.20.4
Derivatives and Hedging Activities - Fair Value of Derivatives by Level (Detail) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Derivative [Line Items]    
Total financial assets at fair value $ 627,073 $ 539,568
Total financial liabilities at fair value (389,577) (332,959)
Fair value included in financial instruments (153,727) (108,835)
Level 1 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 263,999 242,562
Total financial liabilities at fair value (85,120) (54,790)
Level 2 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 410,275 325,259
Total financial liabilities at fair value (331,824) (293,902)
Level 3 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 26,305 23,068
Total financial liabilities at fair value (32,930) (25,938)
Derivatives [Member]    
Derivative [Line Items]    
Total financial assets at fair value 146,751 100,779
Total financial liabilities at fair value (118,888) (85,473)
Fair value included in financial instruments 69,581 45,252
Fair value included in financial instruments (58,591) (43,802)
Derivatives [Member] | Interest Rate Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 358,842 280,003
Total financial liabilities at fair value (321,839) (251,521)
Derivatives [Member] | Credit Risk Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 16,555 20,729
Total financial liabilities at fair value (16,068) (20,789)
Derivatives [Member] | Foreign Exchange Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 102,368 80,365
Total financial liabilities at fair value (103,788) (82,224)
Derivatives [Member] | Commodity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 13,991 11,138
Total financial liabilities at fair value (18,055) (15,549)
Derivatives [Member] | Equity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 76,873 49,661
Total financial liabilities at fair value (81,016) (56,507)
Derivatives [Member] | Gross Fair Value Of Derivative [Member]    
Derivative [Line Items]    
Total financial assets at fair value 568,629 441,896
Total financial liabilities at fair value (540,766) (426,590)
Derivatives [Member] | Counterparty Netting in Levels [Member]    
Derivative [Line Items]    
Total financial assets at fair value (421,878) (341,117)
Total financial liabilities at fair value 421,878 341,117
Derivatives [Member] | Cross Level Counterparty Netting Adjustment [Member]    
Derivative [Line Items]    
Total financial assets at fair value (1,128) 473
Total financial liabilities at fair value 1,128 (473)
Derivatives [Member] | Cash Collateral Netting [Member]    
Derivative [Line Items]    
Cash collateral netting (76,042) (56,000)
Cash collateral netting 59,169 42,144
Derivatives [Member] | Level 1 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 237 24
Total financial liabilities at fair value (412) (29)
Derivatives [Member] | Level 1 [Member] | Interest Rate Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 297 3
Total financial liabilities at fair value (229) (3)
Derivatives [Member] | Level 1 [Member] | Equity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 75 21
Total financial liabilities at fair value (318) (26)
Derivatives [Member] | Level 1 [Member] | Gross Fair Value Of Derivative [Member]    
Derivative [Line Items]    
Total financial assets at fair value 372 24
Total financial liabilities at fair value (547) (29)
Derivatives [Member] | Level 1 [Member] | Counterparty Netting in Levels [Member]    
Derivative [Line Items]    
Total financial assets at fair value (135)  
Total financial liabilities at fair value 135  
Derivatives [Member] | Level 2 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 140,547 96,101
Total financial liabilities at fair value (113,684) (80,815)
Derivatives [Member] | Level 2 [Member] | Interest Rate Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 357,568 279,443
Total financial liabilities at fair value (320,900) (251,050)
Derivatives [Member] | Level 2 [Member] | Credit Risk Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 13,104 17,204
Total financial liabilities at fair value (14,395) (19,141)
Derivatives [Member] | Level 2 [Member] | Foreign Exchange Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 102,221 80,178
Total financial liabilities at fair value (103,303) (81,826)
Derivatives [Member] | Level 2 [Member] | Commodity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 13,285 10,648
Total financial liabilities at fair value (17,649) (15,306)
Derivatives [Member] | Level 2 [Member] | Equity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 75,054 48,953
Total financial liabilities at fair value (78,122) (53,817)
Derivatives [Member] | Level 2 [Member] | Gross Fair Value Of Derivative [Member]    
Derivative [Line Items]    
Total financial assets at fair value 561,232 436,426
Total financial liabilities at fair value (534,369) (421,140)
Derivatives [Member] | Level 2 [Member] | Counterparty Netting in Levels [Member]    
Derivative [Line Items]    
Total financial assets at fair value (420,685) (340,325)
Total financial liabilities at fair value 420,685 340,325
Derivatives [Member] | Level 3 [Member]    
Derivative [Line Items]    
Total financial assets at fair value 5,967 4,654
Total financial liabilities at fair value (4,792) (4,629)
Derivatives [Member] | Level 3 [Member] | Interest Rate Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 977 557
Total financial liabilities at fair value (710) (468)
Derivatives [Member] | Level 3 [Member] | Credit Risk Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 3,451 3,525
Total financial liabilities at fair value (1,673) (1,648)
Derivatives [Member] | Level 3 [Member] | Foreign Exchange Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 147 187
Total financial liabilities at fair value (485) (398)
Derivatives [Member] | Level 3 [Member] | Commodity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 706 490
Total financial liabilities at fair value (406) (243)
Derivatives [Member] | Level 3 [Member] | Equity Contract [Member]    
Derivative [Line Items]    
Total financial assets at fair value 1,744 687
Total financial liabilities at fair value (2,576) (2,664)
Derivatives [Member] | Level 3 [Member] | Gross Fair Value Of Derivative [Member]    
Derivative [Line Items]    
Total financial assets at fair value 7,025 5,446
Total financial liabilities at fair value (5,850) (5,421)
Derivatives [Member] | Level 3 [Member] | Counterparty Netting in Levels [Member]    
Derivative [Line Items]    
Total financial assets at fair value (1,058) (792)
Total financial liabilities at fair value $ 1,058 $ 792