COMMISSIONS AND FEES; ADMINISTRATION AND OTHER FIDUCIARY FEES - Commissions and Fees Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Commissions and fees
Total commissions and fees	$ 2,195	$ 2,139	$ 6,693	$ 7,159
Investment banking
Commissions and fees
Total commissions and fees	694	725	2,018	2,477
Brokerage commissions
Commissions and fees
Total commissions and fees	565	571	1,776	1,999
Interchange fees
Commissions and fees
Total commissions and fees	3,015	2,949	8,944	8,492
Card-related loan fees
Commissions and fees
Total commissions and fees	123	142	360	459
Card rewards and partner payments
Commissions and fees
Total commissions and fees	(3,159)	(3,161)	(9,284)	(9,147)
Deposit-related fees
Commissions and fees
Total commissions and fees	325	300	924	984
Transactional service fees
Commissions and fees
Total commissions and fees	327	295	978	877
Corporate finance
Commissions and fees
Total commissions and fees	89	87	277	342
Insurance distribution revenue
Commissions and fees
Total commissions and fees	77	90	257	267
Insurance premiums
Commissions and fees
Total commissions and fees	26	23	72	72
Loan servicing
Commissions and fees
Total commissions and fees	21	31	71	79
Other
Commissions and fees
Total commissions and fees	92	87	300	258
Overdraft fees
Commissions and fees
Total commissions and fees	0	0	0	59
Commissions and fees
Commissions and fees
Revenue not accounted for under ASC 606, revenue from contracts with customers	(2,897)	(2,872)	(8,497)	(8,115)
ICG
Commissions and fees
Total commissions and fees	1,917	1,886	5,686	6,129
ICG | Investment banking
Commissions and fees
Total commissions and fees	694	725	2,018	2,477
ICG | Brokerage commissions
Commissions and fees
Total commissions and fees	368	356	1,142	1,209
ICG | Interchange fees
Commissions and fees
Total commissions and fees	356	330	1,050	891
ICG | Card-related loan fees
Commissions and fees
Total commissions and fees	16	12	46	32
ICG | Card rewards and partner payments
Commissions and fees
Total commissions and fees	(198)	(175)	(574)	(458)
ICG | Deposit-related fees
Commissions and fees
Total commissions and fees	284	262	808	807
ICG | Transactional service fees
Commissions and fees
Total commissions and fees	298	270	889	791
ICG | Corporate finance
Commissions and fees
Total commissions and fees	89	87	274	339
ICG | Insurance distribution revenue
Commissions and fees
Total commissions and fees	0	0	0	0
ICG | Insurance premiums
Commissions and fees
Total commissions and fees	0	0	0	0
ICG | Loan servicing
Commissions and fees
Total commissions and fees	7	13	24	32
ICG | Other
Commissions and fees
Total commissions and fees	3	6	9	9
PBWM
Commissions and fees
Total commissions and fees	18	(55)	117	43
PBWM | Investment banking
Commissions and fees
Total commissions and fees	0	0	0	0
PBWM | Brokerage commissions
Commissions and fees
Total commissions and fees	176	167	535	621
PBWM | Interchange fees
Commissions and fees
Total commissions and fees	2,507	2,420	7,409	6,954
PBWM | Card-related loan fees
Commissions and fees
Total commissions and fees	36	64	116	201
PBWM | Card rewards and partner payments
Commissions and fees
Total commissions and fees	(2,858)	(2,852)	(8,425)	(8,223)
PBWM | Deposit-related fees
Commissions and fees
Total commissions and fees	32	25	90	128
PBWM | Transactional service fees
Commissions and fees
Total commissions and fees	7	5	17	14
PBWM | Corporate finance
Commissions and fees
Total commissions and fees	0	0	3	3
PBWM | Insurance distribution revenue
Commissions and fees
Total commissions and fees	64	57	183	165
PBWM | Insurance premiums
Commissions and fees
Total commissions and fees	1	1	2	3
PBWM | Loan servicing
Commissions and fees
Total commissions and fees	11	14	37	36
PBWM | Other
Commissions and fees
Total commissions and fees	42	44	150	141
Legacy Franchises
Commissions and fees
Total commissions and fees	262	308	888	987
Legacy Franchises | Investment banking
Commissions and fees
Total commissions and fees	0	0	0	0
Legacy Franchises | Brokerage commissions
Commissions and fees
Total commissions and fees	21	48	99	169
Legacy Franchises | Interchange fees
Commissions and fees
Total commissions and fees	152	199	485	647
Legacy Franchises | Card-related loan fees
Commissions and fees
Total commissions and fees	71	66	198	226
Legacy Franchises | Card rewards and partner payments
Commissions and fees
Total commissions and fees	(103)	(134)	(285)	(466)
Legacy Franchises | Deposit-related fees
Commissions and fees
Total commissions and fees	9	13	26	49
Legacy Franchises | Transactional service fees
Commissions and fees
Total commissions and fees	22	20	72	72
Legacy Franchises | Corporate finance
Commissions and fees
Total commissions and fees	0	0	0	0
Legacy Franchises | Insurance distribution revenue
Commissions and fees
Total commissions and fees	13	33	74	102
Legacy Franchises | Insurance premiums
Commissions and fees
Total commissions and fees	25	22	70	69
Legacy Franchises | Loan servicing
Commissions and fees
Total commissions and fees	3	4	10	11
Legacy Franchises | Other
Commissions and fees
Total commissions and fees	$ 49	$ 37	$ 139	$ 108