LOANS AND LEASES - Schedule of Loans by Class (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 157,190	$ 147,930	$ 144,758
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	130,776	120,734
Commercial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	48,684	44,721
Commercial \| Capital call lines
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	38,126	31,791
Commercial \| Owner occupied commercial mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	18,346	17,660
Commercial \| Investor dependent
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,582	2,778
Commercial \| Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	23,038	23,784
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	26,414	27,196
Consumer \| Residential mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	21,516	21,861
Consumer \| Revolving mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	2,853	2,863
Consumer \| Auto
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,224	1,416
Consumer \| Other consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 821	$ 1,056