LOANS AND LEASES - Nonaccrual Loans by Loan Class (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	$ 166	$ 146
Total nonaccrual loans and leases	931	783
Commercial portfolio \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	76	71
Total nonaccrual loans and leases	562	457
Commercial portfolio \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	81	75
Total nonaccrual loans and leases	133	118
Commercial portfolio \| Lease financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	4	0
Total nonaccrual loans and leases	8	10
Consumer \| Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	5	0
Total nonaccrual loans and leases	107	83
Consumer \| Automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	0	0
Total nonaccrual loans and leases	6	6
Consumer \| Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	0	0
Total nonaccrual loans and leases	113	107
Consumer \| RV and marine
Accounts, Notes, Loans and Financing Receivable [Line Items]
Nonaccrual loans and leases with no ACL	0	0
Total nonaccrual loans and leases	$ 2	$ 2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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