LOANS AND LEASES - Schedule of Loans by Class (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 141,269	$ 140,221	$ 139,341
Global fund banking
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	28,677	27,904
Investor dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,777	3,193
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	113,007	111,993
Commercial | Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	5,714	5,109
Commercial | Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	17,053	16,842
Commercial | Non-owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	16,100	16,194
Commercial | Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	40,658	40,737
Commercial | Leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,028	2,014
Commercial | Global fund banking
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	28,677	27,904
Commercial | Investor dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,777	3,193
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	28,262	28,228
Consumer | Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	23,059	23,152
Consumer | Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,736	2,567
Consumer | Consumer auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,490	1,523
Consumer | Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 977	$ 986