Regulation and Capital Adequacy - Changes in Risk-weighted Assets (Detail) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Standardized
Changes in RWAs [Roll Forward]
Beginning balance	$ 676,863	$ 554,162
Change in Credit RWAs	1,714	114,916
Change in Market RWAs	9,989	7,785
Change in Operational RWAs	0	0
Ending balance	688,566	676,863
Standardized | Regulatory VaR
Changes in RWAs [Roll Forward]
Change in Market RWAs	8,646	(1,403)
Standardized | Stressed VaR
Changes in RWAs [Roll Forward]
Change in Market RWAs	(2,714)	6,944
Standardized | Incremental risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	2,457	(1,015)
Standardized | Comprehensive risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	964	763
Standardized | Specific risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	636	2,496
Standardized | Derivatives
Changes in RWAs [Roll Forward]
Change in Credit RWAs	(7,451)	55,336
Standardized | Commitments, guarantees and loans
Changes in RWAs [Roll Forward]
Change in Credit RWAs	8,926	57,138
Standardized | Securities financing transactions
Changes in RWAs [Roll Forward]
Change in Credit RWAs	1,461	4,919
Standardized | Equity investments
Changes in RWAs [Roll Forward]
Change in Credit RWAs	(11,729)	(3,688)
Standardized | Other
Changes in RWAs [Roll Forward]
Change in Credit RWAs	10,507	1,211
Advanced
Changes in RWAs [Roll Forward]
Beginning balance	647,921	609,750
Change in Credit RWAs	15,453	25,786
Change in Market RWAs	9,989	7,785
Change in Operational RWAs	1,712	4,600
Ending balance	675,075	647,921
Advanced | Regulatory VaR
Changes in RWAs [Roll Forward]
Change in Market RWAs	8,646	(1,403)
Advanced | Stressed VaR
Changes in RWAs [Roll Forward]
Change in Market RWAs	(2,714)	6,944
Advanced | Incremental risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	2,457	(1,015)
Advanced | Comprehensive risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	964	763
Advanced | Specific risk
Changes in RWAs [Roll Forward]
Change in Market RWAs	636	2,496
Advanced | Derivatives
Changes in RWAs [Roll Forward]
Change in Credit RWAs	13,057	(2,159)
Advanced | Commitments, guarantees and loans
Changes in RWAs [Roll Forward]
Change in Credit RWAs	(2,553)	30,623
Advanced | Securities financing transactions
Changes in RWAs [Roll Forward]
Change in Credit RWAs	7,932	(2,161)
Advanced | Equity investments
Changes in RWAs [Roll Forward]
Change in Credit RWAs	(12,417)	(3,686)
Advanced | Other
Changes in RWAs [Roll Forward]
Change in Credit RWAs	$ 9,434	$ 3,169