Loans and Leases - Accruing and Non-Accruing Loans by Class (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	$ 61,853	$ 60,724
Total Accruing	61,963	60,830
Current, non-accruing	372	228
Total Non- Accruing	602	462
Loans and leases	62,565	61,292
30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	89	85
Past due, non-accruing	51	30
90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	21	21
Past due, non-accruing	179	204
Commercial | Commercial, financial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	33,222	32,416
Total Accruing	33,255	32,449
Current, non-accruing	101	113
Total Non- Accruing	173	184
Loans and leases	33,428	32,633
Commercial | Commercial, financial and industrial | General C I
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual, no allowance	172	178
Commercial | Commercial, financial and industrial | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual, no allowance	287	129
Commercial | Commercial, financial and industrial | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	32	32
Past due, non-accruing	26	18
Commercial | Commercial, financial and industrial | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	1	1
Past due, non-accruing	46	53
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,421	14,216
Commercial | Commercial real estate | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,421	14,216
Commercial | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	174	180
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,047	13,650
Consumer | Consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	13,845	13,453
Total Accruing	13,914	13,510
Current, non-accruing	50	73
Total Non- Accruing	133	140
Loans and leases	14,047	13,650
Consumer | Consumer real estate | Home Equity Line of Credit
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual, no allowance	3	4
Consumer | Consumer real estate | R E Installment Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual, no allowance	9	10
Consumer | Consumer real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	50	40
Past due, non-accruing	14	12
Consumer | Consumer real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	19	17
Past due, non-accruing	69	55
Consumer | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	662	783
Total Accruing	667	791
Current, non-accruing	0	1
Total Non- Accruing	2	2
Loans and leases	669	793
Consumer | Credit Card and Other | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	4	5
Past due, non-accruing	1	0
Consumer | Credit Card and Other | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	1	3
Past due, non-accruing	1	1
General C I | Commercial | Commercial, financial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	29,751	30,398
Total Accruing	29,784	30,430
Current, non-accruing	101	108
Total Non- Accruing	173	179
Loans and leases	29,957	30,609
General C I | Commercial | Commercial, financial and industrial | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	32	31
Past due, non-accruing	26	18
General C I | Commercial | Commercial, financial and industrial | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	1	1
Past due, non-accruing	46	53
Loans to mortgage companies | Commercial | Commercial, financial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	3,471	2,018
Total Accruing	3,471	2,019
Current, non-accruing	0	5
Total Non- Accruing	0	5
Loans and leases	3,471	2,024
Loans to mortgage companies | Commercial | Commercial, financial and industrial | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	0	1
Past due, non-accruing	0	0
Loans to mortgage companies | Commercial | Commercial, financial and industrial | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	0	0
Past due, non-accruing	0	0
Commercial Real Estate | Commercial real estate | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	14,124	14,072
Total Accruing	14,127	14,080
Current, non-accruing	221	41
Total Non- Accruing	294	136
Loans and leases	14,421	14,216
Commercial Real Estate | Commercial real estate | Commercial real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	3	8
Past due, non-accruing	10	0
Commercial Real Estate | Commercial real estate | Commercial real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	0	0
Past due, non-accruing	63	95
Home Equity Line of Credit | Consumer | Consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	2,045	2,158
Total Accruing	2,058	2,173
Current, non-accruing	19	30
Total Non- Accruing	34	46
Loans and leases	2,092	2,219
Home Equity Line of Credit | Consumer | Consumer real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	11	11
Past due, non-accruing	4	6
Home Equity Line of Credit | Consumer | Consumer real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	2	4
Past due, non-accruing	11	10
R E Installment Loans | Consumer | Consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	11,800	11,295
Total Accruing	11,856	11,337
Current, non-accruing	31	43
Total Non- Accruing	99	94
Loans and leases	11,955	11,431
R E Installment Loans | Consumer | Consumer real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	39	29
Past due, non-accruing	10	6
R E Installment Loans | Consumer | Consumer real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	17	13
Past due, non-accruing	58	45
Credit card | Consumer | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	262	271
Total Accruing	265	277
Current, non-accruing	0	0
Total Non- Accruing	0	0
Loans and leases	265	277
Credit card | Consumer | Credit Card and Other | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	2	3
Past due, non-accruing	0	0
Credit card | Consumer | Credit Card and Other | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	1	3
Past due, non-accruing	0	0
Other | Consumer | Credit Card and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Current, accruing	400	512
Total Accruing	402	514
Current, non-accruing	0	1
Total Non- Accruing	2	2
Loans and leases	404	516
Other | Consumer | Credit Card and Other | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	2	2
Past due, non-accruing	1	0
Other | Consumer | Credit Card and Other | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due, accruing	0	0
Past due, non-accruing	$ 1	$ 1