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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Modifications (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 3,277
Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 1,011
% of Loan Class	0.38%
Weighted-average interest rate reduction (%)		0.00%
Weighted-average term extension (in months)		12 months
Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
% of Loan Class	0.00%
Weighted-average interest rate reduction (%)		0.00%
Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
% of Loan Class	0.00%
Weighted-average interest rate reduction (%)		0.00%
Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 2,150
% of Loan Class	0.22%
Weighted-average interest rate reduction (%)		0.00%
Weighted-average term extension (in months)		60 months
Weighted-average payment delay (in months)		4 months
Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
% of Loan Class	0.00%
Weighted-average interest rate reduction (%)		0.00%
Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 116
% of Loan Class	0.13%
Weighted-average interest rate reduction (%)		0.00%
Weighted-average term extension (in months)		180 months
Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
% of Loan Class	0.00%
Weighted-average interest rate reduction (%)		0.00%
Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
% of Loan Class	0.00%
Weighted-average interest rate reduction (%)		0.00%
Principal Reduction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0
Principal Reduction | Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	$ 0
Principal Reduction | Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	0
Principal Reduction | Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Principal Reduction	0	$ 0
Interest Rate Reduction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Interest Rate Reduction | Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Term Extension
Financing Receivable, Modifications [Line Items]
Amortized cost basis	1,399
Term Extension | Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	1,011
Term Extension | Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Term Extension | Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Term Extension | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	272
Term Extension | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Term Extension | Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	116
Term Extension | Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Term Extension | Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay
Financing Receivable, Modifications [Line Items]
Amortized cost basis	1,878
Payment Delay | Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	1,878
Payment Delay | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Payment Delay | Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Commercial and Agricultural | Commercial and industrial
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Commercial and Agricultural | Agricultural
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Commercial Mortgages | Construction
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Residential Mortgages
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Consumer Loans | Home equity lines and loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Consumer Loans | Indirect consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	0
Combination | Consumer Loans | Direct consumer loans
Financing Receivable, Modifications [Line Items]
Amortized cost basis	$ 0

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