Loans - Summary of Past Due Loans (Detail) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Carrying Value	$ 184,829	$ 162,135
Total divided by gross loans at amortized cost	0.70%	0.30%
Corporate
Financing Receivable, Past Due [Line Items]
Carrying Value	$ 40,135	$ 37,643
Commercial real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	28,879	29,000
Residential real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	23,035	24,674
Securities-based
Financing Receivable, Past Due [Line Items]
Carrying Value	16,671	16,652
Other collateralized
Financing Receivable, Past Due [Line Items]
Carrying Value	51,702	38,263
Installment
Financing Receivable, Past Due [Line Items]
Carrying Value	6,326	3,672
Credit cards
Financing Receivable, Past Due [Line Items]
Carrying Value	15,820	8,212
Other
Financing Receivable, Past Due [Line Items]
Carrying Value	2,261	4,019
Past due
Financing Receivable, Past Due [Line Items]
Carrying Value	1,168	474
Past due | Corporate
Financing Receivable, Past Due [Line Items]
Carrying Value	92	95
Past due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	409	165
Past due | Residential real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	10	7
Past due | Securities-based
Financing Receivable, Past Due [Line Items]
Carrying Value	1	5
Past due | Other collateralized
Financing Receivable, Past Due [Line Items]
Carrying Value	15
Past due | Installment
Financing Receivable, Past Due [Line Items]
Carrying Value	63	27
Past due | Credit cards
Financing Receivable, Past Due [Line Items]
Carrying Value	556	157
Past due | Other
Financing Receivable, Past Due [Line Items]
Carrying Value	22	18
30-89 days
Financing Receivable, Past Due [Line Items]
Carrying Value	416	136
30-89 days | Corporate
Financing Receivable, Past Due [Line Items]
Carrying Value	0	5
30-89 days | Commercial real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	47	7
30-89 days | Residential real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	4	3
30-89 days | Securities-based
Financing Receivable, Past Due [Line Items]
Carrying Value	1	0
30-89 days | Other collateralized
Financing Receivable, Past Due [Line Items]
Carrying Value	10
30-89 days | Installment
Financing Receivable, Past Due [Line Items]
Carrying Value	46	20
30-89 days | Credit cards
Financing Receivable, Past Due [Line Items]
Carrying Value	291	86
30-89 days | Other
Financing Receivable, Past Due [Line Items]
Carrying Value	17	15
90 days or more
Financing Receivable, Past Due [Line Items]
Carrying Value	752	338
90 days or more | Corporate
Financing Receivable, Past Due [Line Items]
Carrying Value	92	90
90 days or more | Commercial real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	362	158
90 days or more | Residential real estate
Financing Receivable, Past Due [Line Items]
Carrying Value	6	4
90 days or more | Securities-based
Financing Receivable, Past Due [Line Items]
Carrying Value	0	5
90 days or more | Other collateralized
Financing Receivable, Past Due [Line Items]
Carrying Value	5
90 days or more | Installment
Financing Receivable, Past Due [Line Items]
Carrying Value	17	7
90 days or more | Credit cards
Financing Receivable, Past Due [Line Items]
Carrying Value	265	71
90 days or more | Other
Financing Receivable, Past Due [Line Items]
Carrying Value	$ 5	$ 3