LOANS AND LEASES - Additional Information (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($) state	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable	$ 128,600,000	$ 128,400,000	$ 128,600,000
Discount remaining	42,600,000	$ 31,600,000	42,600,000
Number of states, company operating financial services | state		7
Loan modification, accrued interest receivable		$ 200,000	400,000
Loan modification, additional funds		0	100,000
Pooled reserves for all other classes of loans	3,800,000	$ 3,400,000	3,800,000
Minimum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due period for loan to be in default		90 days
Maximum
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past due period for loan to be in default		12 months
Total commercial loans and leases
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans modified, specific reserves	5,300,000	$ 8,100,000	5,300,000
Loans modified, pooled reserves	2,000,000.0	1,800,000	2,000,000.0
Total commercial loans and leases | Commercial Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, collateral dependent		155,000,000
Threshold for loans whose terms have been modified in a trouble debt restructuring, non accrual		1,000,000.0
Residential Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying value of OREO through foreclosure	1,200,000	1,200,000	1,200,000
Mortgage loans on real estate, foreclosure		10,600,000	$ 9,400,000
Indirect Auto Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans sold with servicing retained		800,000,000
Loss from sale of loan, pretax		$ 9,000,000.0
Financing receivable. reclassification to held-for-sale	$ 355,000,000