LOANS AND LEASES - Summary of Loans and Leases Portfolio (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 156,140	$ 128,163
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	81,114	60,350
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	50,989	44,500
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	28,681	14,264
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	1,444	1,586
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	75,026	67,813
Retail | Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	29,548	22,822
Retail | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,684	12,015
Retail | Automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,155	14,549
Retail | Education
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	13,094	12,997
Retail | Other retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	$ 5,545	$ 5,430