v3.22.0.1
Regulation and Capital Adequacy - Changes in Risk-weighted Assets (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Standardized Capital Rules [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Risk-Weighted Assets, Beginning balance $ 554,162 $ 563,575
Change in Credit RWAs 114,916 (13,549)
Change in Market RWAs 7,785 4,136
Change in operational risk 0 0
Risk-Weighted Assets, end of period 676,863 554,162
Standardized Capital Rules [Member] | Derivatives [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 55,336 (614)
Standardized Capital Rules [Member] | Commitments Guarantees and Loans [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 57,138 (3,239)
Standardized Capital Rules [Member] | Securities Financing Transactions [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 4,919 5,560
Standardized Capital Rules [Member] | Equity Investments [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs (3,688) (9,870)
Standardized Capital Rules [Member] | Other [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 1,211 (5,386)
Standardized Capital Rules [Member] | Regulatory VaR [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs (1,403) 5,980
Standardized Capital Rules [Member] | Stressed VaR [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs 6,944 1,067
Standardized Capital Rules [Member] | Incremental Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs (1,015) 3,574
Standardized Capital Rules [Member] | Comprehensive Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs 763 365
Standardized Capital Rules [Member] | Specific Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs 2,496 (6,850)
Advanced Capital Rules [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Risk-Weighted Assets, Beginning balance 609,750 544,653
Change in Credit RWAs 25,786 51,634
Change in Market RWAs 7,785 4,338
Change in operational risk 4,600 9,125
Risk-Weighted Assets, end of period 647,921 609,750
Advanced Capital Rules [Member] | Derivatives [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs (2,159) 39,060
Advanced Capital Rules [Member] | Commitments Guarantees and Loans [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 30,623 17,131
Advanced Capital Rules [Member] | Securities Financing Transactions [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs (2,161) 2,734
Advanced Capital Rules [Member] | Equity Investments [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs (3,686) (12,624)
Advanced Capital Rules [Member] | Other [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Credit RWAs 3,169 5,333
Advanced Capital Rules [Member] | Regulatory VaR [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs (1,403) 5,980
Advanced Capital Rules [Member] | Stressed VaR [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs 6,944 1,067
Advanced Capital Rules [Member] | Incremental Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs (1,015) 3,574
Advanced Capital Rules [Member] | Comprehensive Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs 763 567
Advanced Capital Rules [Member] | Specific Risk [Member]    
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]    
Change in Market RWAs $ 2,496 $ (6,850)