LOANS AND LEASES - Schedule of Loan Modifications (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 6.0	$ 8.3
Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	4.6	1.4
Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	1.3	1.5
Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		0.1
Balloon Payment
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		0.6
Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	0.1	4.7
Commercial real estate \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1.8
% of Total Class of Financing Receivable	0.01%
Term increase from modification	2 months
Commercial real estate \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 0.9
% of Total Class of Financing Receivable		0.01%
Commercial real estate \| Balloon Payment
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 0.6
% of Total Class of Financing Receivable		0.00%
Commercial real estate \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 4.1
% of Total Class of Financing Receivable		0.03%
Commercial real estate \| Other \| Minimum
Financing Receivable, Modified [Line Items]
Term for payment deferrals		3 months
Commercial real estate \| Other \| Maximum
Financing Receivable, Modified [Line Items]
Term for payment deferrals		12 months
Direct installment \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.5	$ 0.2
% of Total Class of Financing Receivable	0.02%	0.01%
Term increase from modification	10 months	114 months
Residential mortgages \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 2.2	$ 0.7
% of Total Class of Financing Receivable	0.03%	0.01%
Term increase from modification	27 months	46 months
Residential mortgages \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1.3	$ 0.6
% of Total Class of Financing Receivable	0.02%	0.01%
Term increase from modification	27 years
Residential mortgages \| Term Extension and Rate Reduction \| Minimum
Financing Receivable, Modified [Line Items]
Term reduction from modification	1.00%
Residential mortgages \| Term Extension and Rate Reduction \| Maximum
Financing Receivable, Modified [Line Items]
Term reduction from modification	4.50%
Residential mortgages \| Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 0.1
% of Total Class of Financing Receivable		0.00%
Term reduction from modification		1.00%
Consumer lines of credit \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1	$ 0.5
% of Total Class of Financing Receivable	0.01%	0.04%
Term increase from modification	221 months	235 months
Commercial and industrial \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1	$ 0.6
% of Total Class of Financing Receivable	0.00%	0.01%

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

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