LOANS AND LEASES - Schedule of Loan Modifications (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 21.9	$ 6.0
Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	19.0	4.6
Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	0.1	1.3
Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	2.8	0.1
Commercial real estate \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 16.9	$ 1.8
% of Total Class of Financing Receivable	0.14%	0.01%
Term increase from modification	13 months	2 months
Commercial and industrial \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1
% of Total Class of Financing Receivable	0.00%
Term increase from modification	65 months
Commercial and industrial \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 2.5	$ 0.1
% of Total Class of Financing Receivable	0.03%	0.00%
Term of modified payment deferral	3 months
Residential mortgages \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 2.0	$ 2.2
% of Total Class of Financing Receivable	0.02%	0.03%
Term increase from modification	32 months	27 months
Residential mortgages \| Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.1	$ 1.3
% of Total Class of Financing Receivable	0.00%	0.02%
Term increase from modification		27 years
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
% of Total Class of Financing Receivable		0.01%
Term increase from modification		221 months
Consumer lines of credit \| Other
Financing Receivable, Modified [Line Items]
Amortized Cost Basis	$ 0.3
% of Total Class of Financing Receivable	0.02%
Direct installment \| Term Extension
Financing Receivable, Modified [Line Items]
Amortized Cost Basis		$ 0.5
% of Total Class of Financing Receivable		0.02%
Term increase from modification		10 months

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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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-Name Accounting Standards Codification
-Section 50
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Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

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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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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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