Regulation and Capital Adequacy - Risk-weighted Assets (Detail) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Standardized
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	$ 602,068	$ 600,354
Total Market RWAs	86,498	76,509
Total Operational RWAs	0	0
Total RWAs	688,566	676,863	$ 554,162
Standardized | Regulatory VaR
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	22,156	13,510
Standardized | Stressed VaR
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	36,208	38,922
Standardized | Incremental risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	9,324	6,867
Standardized | Comprehensive risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	3,485	2,521
Standardized | Specific risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	15,325	14,689
Standardized | Derivatives
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	168,177	175,628
Standardized | Commitments, guarantees and loans
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	242,565	233,639
Standardized | Securities financing transactions
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	77,807	76,346
Standardized | Equity investments
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	31,527	43,256
Standardized | Other
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	81,992	71,485
Advanced
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	453,952	438,499
Total Market RWAs	86,498	76,509
Total Operational RWAs	134,625	132,913
Total RWAs	675,075	647,921	$ 609,750
Advanced | Regulatory VaR
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	22,156	13,510
Advanced | Stressed VaR
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	36,208	38,922
Advanced | Incremental risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	9,324	6,867
Advanced | Comprehensive risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	3,485	2,521
Advanced | Specific risk
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Market RWAs	15,325	14,689
Advanced | Derivatives
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	122,589	109,532
Advanced | Commitments, guarantees and loans
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	179,657	182,210
Advanced | Securities financing transactions
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	22,339	14,407
Advanced | Equity investments
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	33,165	45,582
Advanced | Other
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Credit RWAs	$ 96,202	$ 86,768