Loans and Leases - Schedule of Balances of Loans by Origination Year, Disaggregated by PD Grade and FICO Score - Current Year (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 65,330	$ 64,156
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	2,982	4,551
2025	4,858	5,265
2024	2,653	2,146
2023	2,421	2,991
2022	3,084	1,931
Prior to 2022	5,898	4,240
LMC	4,759	4,703
Revolving Loans	10,402	9,854
Revolving Loans Converted to Term Loans	239	224
Loans and leases	37,296	35,905
Commercial \| Commercial and industrial \| PD Grade 1 -12
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	2,964	4,492
2025	4,743	5,124
2024	2,494	2,012
2023	2,247	2,706
2022	2,812	1,749
Prior to 2022	5,504	3,997
LMC	4,737	4,703
Revolving Loans	9,995	9,448
Revolving Loans Converted to Term Loans	225	210
Loans and leases	35,721	34,441
Commercial \| Commercial and industrial \| PD Grades 13
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	2	7
2025	19	55
2024	59	42
2023	62	78
2022	30	30
Prior to 2022	70	61
LMC	22	0
Revolving Loans	99	123
Revolving Loans Converted to Term Loans	9	6
Loans and leases	372	402
Commercial \| Commercial and industrial \| PD Grades 14 15 16
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	16	52
2025	96	86
2024	100	92
2023	112	207
2022	242	152
Prior to 2022	324	182
LMC	0	0
Revolving Loans	308	283
Revolving Loans Converted to Term Loans	5	8
Loans and leases	1,203	1,062
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,595	13,563
Commercial \| Commercial real estate \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	1,022	1,372
2025	1,672	1,022
2024	991	1,736
2023	1,594	2,985
2022	2,574	2,117
Prior to 2022	5,344	3,866
Revolving Loans	339	372
Revolving Loans Converted to Term Loans	59	93
Loans and leases	13,595	13,563
Commercial \| Commercial real estate \| PD Grade 1 -12 \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	1,022	1,362
2025	1,672	1,011
2024	978	1,726
2023	1,473	2,314
2022	2,086	1,873
Prior to 2022	4,925	3,457
Revolving Loans	305	293
Revolving Loans Converted to Term Loans	59	93
Loans and leases	12,520	12,129
Commercial \| Commercial real estate \| PD Grades 13 \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	0	0
2025	0	0
2024	0	1
2023	36	191
2022	10	92
Prior to 2022	49	88
Revolving Loans	0	33
Revolving Loans Converted to Term Loans	0	0
Loans and leases	95	405
Commercial \| Commercial real estate \| PD Grades 14 15 16 \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	0	10
2025	0	11
2024	13	9
2023	85	480
2022	478	152
Prior to 2022	370	321
Revolving Loans	34	46
Revolving Loans Converted to Term Loans	0	0
Loans and leases	980	1,029
Commercial \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	153	143
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,869	14,108
Consumer \| Consumer Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	661	1,259
2025	1,197	1,315
2024	1,137	1,803
2023	1,630	2,480
2022	2,340	1,913
Prior to 2022	4,741	3,174
Revolving Loans	2,009	2,019
Revolving Loans Converted to Term Loans	154	145
Loans and leases	13,869	14,108
Consumer \| Consumer Real Estate \| FICO score 740 or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	529	920
2025	919	922
2024	918	1,330
2023	1,316	1,830
2022	1,984	1,430
Prior to 2022	3,778	1,924
Revolving Loans	1,510	1,551
Revolving Loans Converted to Term Loans	77	75
Loans and leases	11,031	9,982
Consumer \| Consumer Real Estate \| FICO score 720-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	52	119
2025	83	139
2024	65	173
2023	86	250
2022	85	193
Prior to 2022	231	324
Revolving Loans	162	182
Revolving Loans Converted to Term Loans	12	17
Loans and leases	776	1,397
Consumer \| Consumer Real Estate \| FICO score 700-719
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	36	94
2025	64	90
2024	40	125
2023	86	202
2022	88	159
Prior to 2022	210	250
Revolving Loans	127	134
Revolving Loans Converted to Term Loans	11	14
Loans and leases	662	1,068
Consumer \| Consumer Real Estate \| FICO score 660-699
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	26	92
2025	76	128
2024	60	145
2023	68	163
2022	106	90
Prior to 2022	224	268
Revolving Loans	135	115
Revolving Loans Converted to Term Loans	21	19
Loans and leases	716	1,020
Consumer \| Consumer Real Estate \| FICO score 620-659
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	8	9
2025	33	11
2024	27	10
2023	30	16
2022	34	18
Prior to 2022	116	102
Revolving Loans	38	22
Revolving Loans Converted to Term Loans	11	5
Loans and leases	297	193
Consumer \| Consumer Real Estate \| FICO score less than 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	10	25
2025	22	25
2024	27	20
2023	44	19
2022	43	23
Prior to 2022	182	306
Revolving Loans	37	15
Revolving Loans Converted to Term Loans	22	15
Loans and leases	387	448
Consumer \| Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	21	36
2025	32	15
2024	14	13
2023	13	7
2022	6	4
Prior to 2022	68	58
Revolving Loans	403	437
Revolving Loans Converted to Term Loans	13	10
Loans and leases	570	580
Consumer \| Credit Card and Other \| FICO score 740 or greater
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	7	25
2025	19	8
2024	7	8
2023	8	3
2022	3	2
Prior to 2022	14	8
Revolving Loans	192	197
Revolving Loans Converted to Term Loans	8	6
Loans and leases	258	257
Consumer \| Credit Card and Other \| FICO score 720-739
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	5	2
2025	2	1
2024	1	1
2023	0	0
2022	1	0
Prior to 2022	3	1
Revolving Loans	23	13
Revolving Loans Converted to Term Loans	0	1
Loans and leases	35	19
Consumer \| Credit Card and Other \| FICO score 700-719
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	1	2
2025	2	1
2024	1	0
2023	1	1
2022	0	0
Prior to 2022	2	0
Revolving Loans	24	12
Revolving Loans Converted to Term Loans	2	1
Loans and leases	33	17
Consumer \| Credit Card and Other \| FICO score 660-699
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	0	1
2025	2	0
2024	1	0
2023	1	0
2022	0	0
Prior to 2022	3	1
Revolving Loans	23	6
Revolving Loans Converted to Term Loans	1	1
Loans and leases	31	9
Consumer \| Credit Card and Other \| FICO score 620-659
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	0	1
2025	1	1
2024	0	0
2023	0	0
2022	0	0
Prior to 2022	1	0
Revolving Loans	8	7
Revolving Loans Converted to Term Loans	1	1
Loans and leases	11	10
Consumer \| Credit Card and Other \| FICO score less than 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	8	5
2025	6	4
2024	4	4
2023	3	3
2022	2	2
Prior to 2022	45	48
Revolving Loans	133	202
Revolving Loans Converted to Term Loans	1	0
Loans and leases	$ 202	$ 268

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