LOANS AND LEASES - Summary of Loans and Leases Portfolio (Details) - USD ($) $ in Millions		Jun. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases	[1]	$ 151,320	$ 156,662
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		78,279	82,180
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		48,038	51,836
Commercial | Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		28,947	28,865
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		1,294	1,479
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		73,041	74,482
Retail | Residential mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		30,769	29,921
Retail | Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		14,487	14,043
Retail | Automobile
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		10,428	12,292
Retail | Education
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		12,246	12,808
Retail | Other retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases		$ 5,111	$ 5,418

[1] Includes amounts in consolidated VIEs. See Note 6 for additional information.