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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Modifications (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	$ 992	$ 440	$ 3,187
Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		$ 440
% of Loan Class		0.16%
Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	$ 875		$ 3,070
% of Loan Class	0.09%		0.32%
Weighted-average interest rate reduction	0.00%	0.00%	0.00%
Weighted-average term extension	6 months	0 months	19 months
Weighted-average payment delay	0 months	6 months	4 months
Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			$ 117
% of Loan Class			0.13%
Weighted-average interest rate reduction			0.00%
Weighted-average term extension			180 months
Weighted-average payment delay	0 months		0 months
Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	$ 117
% of Loan Class	0.13%
Weighted-average interest rate reduction	0.00%
Weighted-average term extension	180 months
Principal Forgiveness
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	$ 0	$ 0	$ 0
Principal Forgiveness | Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		0
Principal Forgiveness | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0		0
Principal Reduction	0	0	0
Principal Forgiveness | Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			0
Principal Reduction	0		0
Principal Forgiveness | Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0
Principal Reduction	0		0
Contractual Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0	0	0
Contractual Interest Rate Reduction | Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		0
Contractual Interest Rate Reduction | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0		0
Contractual Interest Rate Reduction | Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			0
Contractual Interest Rate Reduction | Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0
Extended Maturity
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	992	0	1,267
Extended Maturity | Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		0
Extended Maturity | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	875		1,150
Extended Maturity | Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			117
Extended Maturity | Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	117
Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0	440	1,920
Payment Deferral | Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		440
Payment Deferral | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0		1,920
Payment Deferral | Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			0
Payment Deferral | Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0
Combination
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0	0	0
Combination | Residential Mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis		$ 0
Combination | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	0		0
Combination | Commercial Mortgages | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis			$ 0
Combination | Consumer Loans | Home equity lines and loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Amortized cost basis	$ 0

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