LOANS AND LEASES - Schedule of Loan Modifications (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 19.6	$ 5.1	$ 41.5	$ 10.7
Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	2.2	2.9	21.2	7.1
Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	12.8		12.9	1.3
Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	4.6	2.2	7.4	2.3
Commercial real estate \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1		$ 17.0	$ 1.5
% of Total Class of Financing Receivable	0.00%		0.14%	0.01%
Term increase from modification			13 months	2 months
Commercial real estate \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 11.8		$ 11.8
% of Total Class of Financing Receivable	0.10%		0.10%
Term increase from modification	15 months		15 months
Interest rate reduction from modification	3.00%		3.00%
Commercial real estate \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 3.0	$ 1.3	$ 3.0	$ 1.3
% of Total Class of Financing Receivable	0.02%	0.01%	0.02%	0.01%
Term of modified payment deferral	3 months	3 months	3 months	3 months
Commercial and industrial \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.2	$ 0.8	$ 0.3	$ 0.8
% of Total Class of Financing Receivable	0.00%	0.01%	0.00%	0.01%
Term increase from modification		29 months		29 months
Commercial and industrial \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1.6	$ 0.9	$ 4.1	$ 1.0
% of Total Class of Financing Receivable	0.02%	0.01%	0.05%	0.01%
Term of modified payment deferral	3 months	3 months	3 months	3 months
Direct installment \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.6	$ 1.0	$ 0.7	$ 1.5
% of Total Class of Financing Receivable	0.02%	0.04%	0.03%	0.06%
Term increase from modification	17 months	26 months	17 months	21 months
Direct installment \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1		$ 0.1
% of Total Class of Financing Receivable	0.00%		0.00%
Residential mortgages \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 1.2	$ 0.8	$ 3.1	$ 2.9
% of Total Class of Financing Receivable	0.01%	0.01%	0.03%	0.03%
Term increase from modification	50 months	26 months	42 months	27 months
Residential mortgages \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.9		$ 1.0	$ 1.3
% of Total Class of Financing Receivable	0.01%		0.01%	0.02%
Term increase from modification	53 months		78 months	27 years
Interest rate reduction from modification	2.93%		2.56%
Residential mortgages \| Term Extension and Rate Reduction \| Minimum
Financing Receivable, Modified [Line Items]
Interest rate reduction from modification				1.00%
Residential mortgages \| Term Extension and Rate Reduction \| Maximum
Financing Receivable, Modified [Line Items]
Interest rate reduction from modification				4.50%
Consumer lines of credit \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1	$ 0.3	$ 0.1	$ 0.4
% of Total Class of Financing Receivable	0.01%	0.02%	0.01%	0.03%
Term increase from modification				181 months
Consumer lines of credit \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis			$ 0.3
% of Total Class of Financing Receivable			0.02%

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- Definition

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

+ References

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-Topic 310
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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