Loans and Leases - Performance of Loans that have been Modified in the Last 12 Months (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accruing	$ 185	$ 71	$ 80
Financing Receivable, Excluding Accrued Interest, Modified, After 12 Months, Including Nonaccruring	481	384	162
Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	289	313	82
30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	7	0	0
90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
C&I
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accruing	55	24	22
Financing Receivable, Excluding Accrued Interest, Modified, After 12 Months, Including Nonaccruring	195	140	92
C&I | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	133	116	70
C&I | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	7	0	0
C&I | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
CRE
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accruing	128	46	47
Financing Receivable, Excluding Accrued Interest, Modified, After 12 Months, Including Nonaccruring	283	241	55
CRE | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	155	195	8
CRE | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
CRE | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
Consumer real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accruing	2	1	11
Financing Receivable, Excluding Accrued Interest, Modified, After 12 Months, Including Nonaccruring	3	3	15
Consumer real estate | Current
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	1	2	4
Consumer real estate | 30-89 Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	0	0	0
Consumer real estate | 90+ Days Past Due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans	$ 0	$ 0	$ 0