LOANS AND LEASES - Summary of Loans and Leases Portfolio (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 139,203	$ 145,959
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	69,776	74,445
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	42,551	44,974
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	27,225	29,471
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	69,427	71,514
Retail | Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	32,726	31,332
Retail | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	16,495	15,040
Retail | Automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	4,744	8,258
Retail | Education
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	10,812	11,834
Retail | Other retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 4,650	$ 5,050