Off-balance Sheet Lending-related Financial Instruments, Guarantees, and Other Commitments (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	$ 1,714,006	$ 1,577,622
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	1,237,740
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	221,063
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	214,809
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	40,394
Off-balance sheet lending-related financial commitments, Carrying value	4,231	3,689
Total Consumer
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	1,117,978	1,046,155
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	1,097,771
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	6,114
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	3,698
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	10,395
Off-balance sheet lending-related financial commitments, Carrying value	375	571
Total consumer, excluding credit card
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	48,015	44,844
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	27,808
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	6,114
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	3,698
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	10,395
Off-balance sheet lending-related financial commitments, Carrying value	375	571
Residential real estate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	33,599	30,349
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	17,227
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	6,113
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	3,694
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	6,565
Off-balance sheet lending-related financial commitments, Carrying value	365	534
Auto and other
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	14,416	14,495
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	10,581
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	1
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	4
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	3,830
Off-balance sheet lending-related financial commitments, Carrying value	10	37
Credit card
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	1,069,963	1,001,311
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	1,069,963
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	0
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	0
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	0
Off-balance sheet lending-related financial commitments, Carrying value	0	0
Total wholesale
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	596,028	531,467
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	139,969
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	214,949
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	211,111
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	29,999
Off-balance sheet lending-related financial commitments, Carrying value	3,856	3,118
Other unfunded commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	563,124	498,437
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	121,187
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	206,396
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	206,311
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	29,230
Off-balance sheet lending-related financial commitments, Carrying value	3,243	2,608
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information
Risk participations for other unfunded commitments to extend credit	176	85
Standby letters of credit and other financial guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	28,892	28,676
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	15,308
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	8,241
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	4,793
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	550
Off-balance sheet lending-related financial commitments, Carrying value	601	473
Other guarantees and commitments, Carrying value	426	379
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information
Risk participations for standby letters of credit and other financial guarantees	12,500	9,500
Other letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Total lending-related commitments	4,012	4,354
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring in 1 year or less	3,474
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 1 year through 3 years	312
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 3 years through 5 years	7
Off-balance sheet lending-related financial commitments, Contractual amount, Expiring after 5 years	219
Off-balance sheet lending-related financial commitments, Carrying value	12	37
Other guarantees and commitments, Carrying value	0	0
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information
Risk participations for other letters of credit	557	556
Securities lending indemnification agreements and guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	386,993	310,046
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	386,993
Other guarantees and commitments, Contractual amount, Expiring after 1 year through 3 years	0
Other guarantees and commitments, Contractual amount, Expiring after 3 years through 5 years	0
Other guarantees and commitments, Contractual amount, Expiring after 5 years	0
Other guarantees and commitments, Carrying value	0	0
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information
Collateral held in support of securities lending indemnification agreements	410,700	328,700
Derivatives qualifying as guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	50,902	49,628
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	3,524
Other guarantees and commitments, Contractual amount, Expiring after 1 year through 3 years	693
Other guarantees and commitments, Contractual amount, Expiring after 3 years through 5 years	9,531
Other guarantees and commitments, Contractual amount, Expiring after 5 years	37,154
Other guarantees and commitments, Carrying value	11	113
Unsettled resale and securities borrowed agreements
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	136,263	115,939
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	135,013
Other guarantees and commitments, Contractual amount, Expiring after 1 year through 3 years	0
Other guarantees and commitments, Contractual amount, Expiring after 3 years through 5 years	1,250
Other guarantees and commitments, Contractual amount, Expiring after 5 years	0
Other guarantees and commitments, Carrying value	0	2
Unsettled repurchase and securities loaned agreements
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	117,800	66,986
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	117,212
Other guarantees and commitments, Contractual amount, Expiring after 1 year through 3 years	588
Other guarantees and commitments, Contractual amount, Expiring after 3 years through 5 years	0
Other guarantees and commitments, Contractual amount, Expiring after 5 years	0
Other guarantees and commitments, Carrying value	0	(2)
Mortgage repurchase liability
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loan sale and securitization-related indemnifications, Mortgage repurchase liability, Carrying value	36	45
Loans sold with recourse
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loan sale and securitization-related indemnifications, Loans sold with recourse, Contractual amount	1,899	1,189
Loan sale and securitization-related indemnifications, Loans sold with recourse, Carrying value	20	23
Exchange & clearing house guarantees and commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	342,887	401,486
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	342,887
Other guarantees and commitments, Carrying value	0	0
Other guarantees and commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, Contractual amount	16,858	12,396
Other guarantees and commitments, Contractual amount, Expiring in 1 year or less	14,634
Other guarantees and commitments, Contractual amount, Expiring after 1 year through 3 years	991
Other guarantees and commitments, Contractual amount, Expiring after 3 years through 5 years	442
Other guarantees and commitments, Contractual amount, Expiring after 5 years	791
Other guarantees and commitments, Carrying value	$ 18	$ 28