Business Segment Information - Amounts of Consolidated Revenue, Expense, Tax and Assets by Segment (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2025	Sep. 30, 2024
Disaggregation of Revenue [Line Items]
Interest income	$ 1,077			$ 1,119			$ 3,135	$ 3,284
Interest expense	403			492			1,189	1,403
Funds transfer pricing	0			0			0	0
Net interest income (expense)	674			627			1,946	1,881
Noninterest income	215			200			585	581
Total revenues	889			827			2,531	2,462
Noninterest expense	550			511			1,529	1,527
Pre-provision net revenue	339			316			1,002	935
Provision for credit losses	(5)			35			65	140
Income (loss) before income taxes	344			281			937	795
Income tax expense (benefit)	78			58			205	171
Net income (loss)	266	$ 245	$ 222	223	$ 204	$ 197	732	624
Average assets	82,049			82,366			81,661	81,779
Depreciation and amortization	6			31			47	82
Expenditures for long-lived assets	6			7			23	28
Commercial, Consumer & Wealth
Disaggregation of Revenue [Line Items]
Interest income	855			905			2,494	2,681
Interest expense	300			372			886	1,075
Funds transfer pricing	105			101			308	291
Net interest income (expense)	660			634			1,916	1,897
Noninterest income	117			119			340	345
Total revenues	777			753			2,256	2,242
Noninterest expense	365			352			1,063	1,056
Pre-provision net revenue	412			401			1,193	1,186
Provision for credit losses	2			42			52	143
Income (loss) before income taxes	410			359			1,141	1,043
Income tax expense (benefit)	98			85			271	246
Net income (loss)	312			274			870	797
Average assets	58,827			59,503			58,760	59,503
Depreciation and amortization	(5)			15			12	33
Expenditures for long-lived assets	5			4			15	15
Wholesale
Disaggregation of Revenue [Line Items]
Interest income	142			141			406	386
Interest expense	27			31			81	96
Funds transfer pricing	(55)			(58)			(157)	(151)
Net interest income (expense)	60			52			168	139
Noninterest income	73			56			187	172
Total revenues	133			108			355	311
Noninterest expense	83			75			235	223
Pre-provision net revenue	50			33			120	88
Provision for credit losses	(1)			(7)			9	1
Income (loss) before income taxes	51			40			111	87
Income tax expense (benefit)	12			10			27	21
Net income (loss)	39			30			84	66
Average assets	9,356			8,440			9,056	7,871
Depreciation and amortization	2			2			6	6
Expenditures for long-lived assets	0			0			1	1
Corporate
Disaggregation of Revenue [Line Items]
Interest income	80			73			235	217
Interest expense	76			89			222	232
Funds transfer pricing	(50)			(43)			(151)	(140)
Net interest income (expense)	(46)			(59)			(138)	(155)
Noninterest income	25			25			58	64
Total revenues	(21)			(34)			(80)	(91)
Noninterest expense	102			84			231	248
Pre-provision net revenue	(123)			(118)			(311)	(339)
Provision for credit losses	(6)			0			4	(4)
Income (loss) before income taxes	(117)			(118)			(315)	(335)
Income tax expense (benefit)	(32)			(37)			(93)	(96)
Net income (loss)	(85)			(81)			(222)	(239)
Average assets	13,866			14,423			13,845	14,405
Depreciation and amortization	9			14			29	43
Expenditures for long-lived assets	1			3			7	12
Deferred compensation expense credit							4
Special assessment fee expense (credit)	(2)			(2)			(2)	10
Restructuring costs				2				10
Corporate | Visa Class B Shares
Disaggregation of Revenue [Line Items]
Derivative valuation adjustment prior sales of Visa Class B shares	$ 10			$ 15			$ 15	$ 15