Business Segments - Results of Operations and Average Assets by Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information
Net interest income (FTE)	$ 1,525	$ 1,427	$ 4,468	$ 4,210
Provision for (benefit from) credit losses	197	160	544	351
Net interest income after provision for (benefit from) credit losses	1,328	1,267	3,924	3,859
Noninterest Income
Wealth and asset management revenue	181	163	519	483
Commercial payments revenue	157	154	462	453
Consumer banking revenue	144	143	428	418
Capital markets fees	115	111	294	301
Commercial banking revenue	87	93	247	267
Mortgage banking net revenue	58	50	171	154
Other noninterest income (loss)	29	(13)	86	18
Securities gains, net	10	10	17	23
Total noninterest income	781	711	2,224	2,117
Noninterest Expense
Compensation and benefits	685	690	2,132	2,099
Technology and communications	128	121	378	351
Net occupancy expense	89	81	260	251
Equipment expense	44	38	126	114
Loan and lease expense	39	34	105	96
Marketing expense	34	26	105	92
Card and processing expense	22	22	65	63
Other noninterest expense	226	232	664	741
Total noninterest expense	1,267	1,244	3,835	3,807
Income (loss) before income taxes (FTE)	842	734	2,313	2,169
Average assets	211,770	213,838	210,965	213,174
Operating Segments | Commercial Banking
Segment Reporting Information
Net interest income (FTE)	594	648	1,742	1,946
Provision for (benefit from) credit losses	246	76	405	284
Net interest income after provision for (benefit from) credit losses	348	572	1,337	1,662
Noninterest Income
Wealth and asset management revenue	1	1	1	2
Commercial payments revenue	140	131	404	386
Consumer banking revenue	0	0	0	0
Capital markets fees	114	110	292	298
Commercial banking revenue	86	92	243	265
Mortgage banking net revenue	0	0	0	0
Other noninterest income (loss)	16	11	44	42
Securities gains, net	0	9	(7)	3
Total noninterest income	357	354	977	996
Noninterest Expense
Compensation and benefits	151	148	480	487
Technology and communications	5	3	10	10
Net occupancy expense	9	9	27	26
Equipment expense	8	7	24	21
Loan and lease expense	10	8	25	20
Marketing expense	1	1	4	2
Card and processing expense	3	2	9	6
Other noninterest expense	267	282	839	822
Total noninterest expense	454	460	1,418	1,394
Income (loss) before income taxes (FTE)	251	466	896	1,264
Average assets	77,603	75,550	77,949	76,621
FTE adjustments	3	4	9	11
Operating Segments | Consumer and Small Business Banking
Segment Reporting Information
Net interest income (FTE)	1,082	1,056	3,141	3,287
Provision for (benefit from) credit losses	73	78	241	232
Net interest income after provision for (benefit from) credit losses	1,009	978	2,900	3,055
Noninterest Income
Wealth and asset management revenue	73	64	206	185
Commercial payments revenue	22	22	64	65
Consumer banking revenue	144	142	426	415
Capital markets fees	1	1	2	2
Commercial banking revenue	1	1	3	2
Mortgage banking net revenue	58	50	170	153
Other noninterest income (loss)	10	3	13	5
Securities gains, net	0	0	0	0
Total noninterest income	309	283	884	827
Noninterest Expense
Compensation and benefits	232	209	697	675
Technology and communications	8	7	24	22
Net occupancy expense	55	52	163	160
Equipment expense	14	13	43	38
Loan and lease expense	22	21	61	61
Marketing expense	20	15	69	55
Card and processing expense	19	20	55	57
Other noninterest expense	283	277	836	834
Total noninterest expense	653	614	1,948	1,902
Income (loss) before income taxes (FTE)	665	647	1,836	1,980
Average assets	56,762	52,552	55,630	51,920
Operating Segments | Wealth and Asset Management
Segment Reporting Information
Net interest income (FTE)	55	50	161	162
Provision for (benefit from) credit losses	0	0	(2)	0
Net interest income after provision for (benefit from) credit losses	55	50	163	162
Noninterest Income
Wealth and asset management revenue	107	98	312	296
Commercial payments revenue	0	0	1	1
Consumer banking revenue	1	1	2	2
Capital markets fees	0	0	1	1
Commercial banking revenue	0	0	1	0
Mortgage banking net revenue	0	0	1	1
Other noninterest income (loss)	1	0	2	1
Securities gains, net	0	0	0	0
Total noninterest income	109	99	320	302
Noninterest Expense
Compensation and benefits	53	54	170	168
Technology and communications	0	0	0	1
Net occupancy expense	3	3	10	9
Equipment expense	0	0	0	0
Loan and lease expense	0	0	1	0
Marketing expense	0	0	0	1
Card and processing expense	0	0	1	1
Other noninterest expense	37	38	114	112
Total noninterest expense	93	95	296	292
Income (loss) before income taxes (FTE)	71	54	187	172
Average assets	4,910	4,374	4,808	4,357
General Corporate and Other
Segment Reporting Information
Net interest income (FTE)	(206)	(327)	(576)	(1,185)
Provision for (benefit from) credit losses	(122)	6	(100)	(165)
Net interest income after provision for (benefit from) credit losses	(84)	(333)	(476)	(1,020)
Noninterest Income
Wealth and asset management revenue	0	0	0	0
Commercial payments revenue	(5)	1	(7)	1
Consumer banking revenue	(1)	0	0	1
Capital markets fees	0	0	(1)	0
Commercial banking revenue	0	0	0	0
Mortgage banking net revenue	0	0	0	0
Other noninterest income (loss)	2	(27)	27	(30)
Securities gains, net	10	1	24	20
Total noninterest income	6	(25)	43	(8)
Noninterest Expense
Compensation and benefits	249	279	785	769
Technology and communications	115	111	344	318
Net occupancy expense	22	17	60	56
Equipment expense	22	18	59	55
Loan and lease expense	7	5	18	15
Marketing expense	13	10	32	34
Card and processing expense	0	0	0	(1)
Other noninterest expense	(361)	(365)	(1,125)	(1,027)
Total noninterest expense	67	75	173	219
Income (loss) before income taxes (FTE)	(145)	(433)	(606)	(1,247)
Average assets	72,495	81,362	72,578	80,276
FTE adjustments	$ 2	$ 2	$ 6	$ 7