LOANS AND LEASES - Loan Modifications, Subsequently Defaulted (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	$ 28.2	$ 2.0
Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	22.4
Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.6
Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	5.2
Total commercial loans and leases
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	27.4	1.0
Total commercial loans and leases | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	21.9
Total commercial loans and leases | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.3
Total commercial loans and leases | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	5.2
Total commercial loans and leases | Commercial real estate
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	5.6	1.0
Total commercial loans and leases | Commercial real estate | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.4
Total commercial loans and leases | Commercial real estate | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total commercial loans and leases | Commercial real estate | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	5.2
Total commercial loans and leases | Commercial and industrial
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	21.8	$ 0.0
Total commercial loans and leases | Commercial and industrial | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	21.5
Total commercial loans and leases | Commercial and industrial | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.3
Total commercial loans and leases | Commercial and industrial | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.8
Total consumer loans | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.5
Total consumer loans | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.3
Total consumer loans | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans | Direct installment
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.1
Total consumer loans | Direct installment | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.1
Total consumer loans | Direct installment | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans | Direct installment | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans | Residential mortgages
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.6
Total consumer loans | Residential mortgages | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.3
Total consumer loans | Residential mortgages | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.3
Total consumer loans | Residential mortgages | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans | Consumer lines of credit
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.1
Total consumer loans | Consumer lines of credit | Term Extension
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.1
Total consumer loans | Consumer lines of credit | Term Extension and Rate Reduction
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	0.0
Total consumer loans | Consumer lines of credit | Other
Financing Receivable, Modified [Line Items]
Total loans that subsequently defaulted	$ 0.0