Business Segment Information - Amounts of Consolidated Revenue, Expense, Tax and Assets by Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Interest income	$ 1,014	$ 1,073
Interest expense	383	448
Funds transfer pricing	0	0
Net interest income	631	625
Noninterest income	181	194
Total revenues	812	819
Total noninterest expense	487	515
Pre-provision net revenue	325	304
Provision for credit losses	40	50
Income (loss) before income taxes	285	254
Income tax expense (benefit)	63	57
Net income (loss)	222	197
Average assets	80,965	81,243
Depreciation and amortization	21	26
Expenditures for long-lived assets	9	9
Commercial, Consumer & Wealth
Disaggregation of Revenue [Line Items]
Interest income	814	882
Interest expense	291	351
Funds transfer pricing	101	94
Net interest income	624	625
Noninterest income	110	110
Total revenues	734	735
Total noninterest expense	343	347
Pre-provision net revenue	391	388
Provision for credit losses	38	44
Income (loss) before income taxes	353	344
Income tax expense (benefit)	84	81
Net income (loss)	269	263
Average assets	58,717	59,348
Depreciation and amortization	9	9
Expenditures for long-lived assets	5	4
Wholesale
Disaggregation of Revenue [Line Items]
Interest income	124	115
Interest expense	28	31
Funds transfer pricing	(46)	(42)
Net interest income	50	42
Noninterest income	59	62
Total revenues	109	104
Total noninterest expense	77	75
Pre-provision net revenue	32	29
Provision for credit losses	3	7
Income (loss) before income taxes	29	22
Income tax expense (benefit)	7	5
Net income (loss)	22	17
Average assets	8,495	7,146
Depreciation and amortization	2	2
Expenditures for long-lived assets	1	0
Corporate
Disaggregation of Revenue [Line Items]
Interest income	76	76
Interest expense	64	66
Funds transfer pricing	(55)	(52)
Net interest income	(43)	(42)
Noninterest income	12	22
Total revenues	(31)	(20)
Total noninterest expense	67	93
Pre-provision net revenue	(98)	(113)
Provision for credit losses	(1)	(1)
Income (loss) before income taxes	(97)	(112)
Income tax expense (benefit)	(28)	(29)
Net income (loss)	(69)	(83)
Average assets	13,753	14,749
Depreciation and amortization	10	15
Expenditures for long-lived assets	3	5
Special assessment fee	1	10
Restructuring costs		$ 5
Corporate | Visa Class B Shares
Disaggregation of Revenue [Line Items]
Derivative valuation adjustment prior sales of visa class b shares	$ 5