Loans and Leases - Balances Of Commercial Loan Portfolio Classes, Disaggregated By PD Grade (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 61,292	$ 58,102
C&I | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	4,125	7,509
Financing receivable, originated year two	5,833	3,738
Financing receivable, originated year three	3,665	1,861
Financing receivable, originated year four	1,743	2,071
Financing receivable, originated year five	1,806	1,145
Financing receivable, originated prior to year five	3,606	3,305
LMC, Non-Revolving Loans	2,019	2,258
Revolving loans	9,460	9,426
Revolving Loans converted to term loans	376	468
Loans and leases	32,633	31,781
C&I | PD Grade 1 -12 | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	4,009	7,456
Financing receivable, originated year two	5,638	3,634
Financing receivable, originated year three	3,507	1,803
Financing receivable, originated year four	1,636	1,912
Financing receivable, originated year five	1,666	1,112
Financing receivable, originated prior to year five	3,449	3,170
LMC, Non-Revolving Loans	2,014	2,258
Revolving loans	9,087	9,166
Revolving Loans converted to term loans	327	371
Loans and leases	31,333	30,882
C&I | PD Grades 13 | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	75	17
Financing receivable, originated year two	60	56
Financing receivable, originated year three	64	17
Financing receivable, originated year four	56	125
Financing receivable, originated year five	101	8
Financing receivable, originated prior to year five	57	80
LMC, Non-Revolving Loans	0	0
Revolving loans	186	126
Revolving Loans converted to term loans	0	0
Loans and leases	599	429
C&I | PD Grades 14 15 16 | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	41	36
Financing receivable, originated year two	135	48
Financing receivable, originated year three	94	41
Financing receivable, originated year four	51	34
Financing receivable, originated year five	39	25
Financing receivable, originated prior to year five	100	55
LMC, Non-Revolving Loans	5	0
Revolving loans	187	134
Revolving Loans converted to term loans	49	97
Loans and leases	701	470
Commercial real estate | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	14,216	13,228
Commercial real estate | CRE | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	858	2,638
Financing receivable, originated year two	3,476	3,331
Financing receivable, originated year three	3,652	1,503
Financing receivable, originated year four	1,259	1,942
Financing receivable, originated year five	1,566	907
Financing receivable, originated prior to year five	2,994	2,601
Revolving loans	393	286
Revolving Loans converted to term loans	18	20
Loans and leases	14,216	13,228
Commercial real estate | PD Grade 1 -12 | CRE | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	853	2,637
Financing receivable, originated year two	3,473	3,324
Financing receivable, originated year three	3,518	1,488
Financing receivable, originated year four	1,162	1,855
Financing receivable, originated year five	1,216	808
Financing receivable, originated prior to year five	2,853	2,565
Revolving loans	393	274
Revolving Loans converted to term loans	18	20
Loans and leases	13,486	12,971
Commercial real estate | PD Grades 13 | CRE | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	5	0
Financing receivable, originated year two	1	3
Financing receivable, originated year three	129	3
Financing receivable, originated year four	86	37
Financing receivable, originated year five	175	68
Financing receivable, originated prior to year five	82	5
Revolving loans	0	1
Revolving Loans converted to term loans	0	0
Loans and leases	478	117
Commercial real estate | PD Grades 14 15 16 | CRE | Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, originated year one	0	1
Financing receivable, originated year two	2	4
Financing receivable, originated year three	5	12
Financing receivable, originated year four	11	50
Financing receivable, originated year five	175	31
Financing receivable, originated prior to year five	59	31
Revolving loans	0	11
Revolving Loans converted to term loans	0	0
Loans and leases	$ 252	$ 140