FAIR VALUE MEASUREMENTS AND FAIR VALUES OF FINANCIAL INSTRUMENTS - Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Assets Measured at Fair Value
Total, fair value	$ 429,138	$ 498,033
Impaired loans with a valuation allowance		3,460
Valuation allowance		(453)
Impaired loans, net		3,460
Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	4,545	3,638
Fair value of the derivative liability	4,545	3,638
Obligations of the U.S. Treasury
Assets Measured at Fair Value
Total, fair value	30,557	31,836
Obligations of U.S. Government agencies
Assets Measured at Fair Value
Total, fair value	18,796	23,430
Bank holding company debt securities
Assets Measured at Fair Value
Total, fair value	22,311	25,386
Obligations Of States And Political Subdivisions Tax Exempt
Assets Measured at Fair Value
Total, fair value	104,453	132,623
Obligations Of States And Political Subdivisions Taxable
Assets Measured at Fair Value
Total, fair value	53,457	56,812
Residential Passthrough Securities
Assets Measured at Fair Value
Total, fair value	94,469	99,941
Residential Collateralized Mortgage Obligations
Assets Measured at Fair Value
Total, fair value	33,397	40,296
Commercial Mortgage Backed Securities
Assets Measured at Fair Value
Total, fair value	63,672	79,686
Private label commercial mortgage-backed securities
Assets Measured at Fair Value
Total, fair value	8,026	8,023
Recurring fair value measurements
Assets Measured at Fair Value
Total, fair value	429,138	498,033
Marketable equity security	832	859
Servicing rights	2,630	2,653
Total asset fair value measurements	437,151	505,183
Recurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total, fair value	30,557	31,836
Marketable equity security	832	859
Servicing rights	0	0
Total asset fair value measurements	31,389	32,695
Recurring fair value measurements \| Level 2
Assets Measured at Fair Value
Total, fair value	398,581	466,197
Marketable equity security	0	0
Servicing rights	0	0
Total asset fair value measurements	403,132	469,835
Recurring fair value measurements \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Marketable equity security	0	0
Servicing rights	2,630	2,653
Total asset fair value measurements	2,630	2,653
Recurring fair value measurements \| RPA Out
Assets Measured at Fair Value
Fair value derivative asset	6
Recurring fair value measurements \| RPA Out \| Level 1
Assets Measured at Fair Value
Fair value derivative asset	0
Recurring fair value measurements \| RPA Out \| Level 2
Assets Measured at Fair Value
Fair value derivative asset	6
Recurring fair value measurements \| RPA Out \| Level 3
Assets Measured at Fair Value
Fair value derivative asset	0
Recurring fair value measurements \| Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	4,545	3,638
Fair value of the derivative liability	4,545	3,638
Recurring fair value measurements \| Interest rate swap agreements \| Level 1
Assets Measured at Fair Value
Fair value derivative asset	0	0
Fair value of the derivative liability	0	0
Recurring fair value measurements \| Interest rate swap agreements \| Level 2
Assets Measured at Fair Value
Fair value derivative asset	4,545	3,638
Fair value of the derivative liability	4,545	3,638
Recurring fair value measurements \| Interest rate swap agreements \| Level 3
Assets Measured at Fair Value
Fair value derivative asset	0	0
Fair value of the derivative liability	0	0
Recurring fair value measurements \| Obligations of the U.S. Treasury
Assets Measured at Fair Value
Total, fair value	30,557	31,836
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 1
Assets Measured at Fair Value
Total, fair value	30,557	31,836
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 2
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations of U.S. Government agencies
Assets Measured at Fair Value
Total, fair value	18,796	23,430
Recurring fair value measurements \| Obligations of U.S. Government agencies \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations of U.S. Government agencies \| Level 2
Assets Measured at Fair Value
Total, fair value	18,796	23,430
Recurring fair value measurements \| Obligations of U.S. Government agencies \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Bank holding company debt securities
Assets Measured at Fair Value
Total, fair value	22,311	25,386
Recurring fair value measurements \| Bank holding company debt securities \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Bank holding company debt securities \| Level 2
Assets Measured at Fair Value
Total, fair value	22,311	25,386
Recurring fair value measurements \| Bank holding company debt securities \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Tax Exempt
Assets Measured at Fair Value
Total, fair value	104,453	132,623
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Tax Exempt \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Tax Exempt \| Level 2
Assets Measured at Fair Value
Total, fair value	104,453	132,623
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Tax Exempt \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Taxable
Assets Measured at Fair Value
Total, fair value	53,457	56,812
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Taxable \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Taxable \| Level 2
Assets Measured at Fair Value
Total, fair value	53,457	56,812
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Taxable \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Residential Passthrough Securities
Assets Measured at Fair Value
Total, fair value	94,469	99,941
Recurring fair value measurements \| Residential Passthrough Securities \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Residential Passthrough Securities \| Level 2
Assets Measured at Fair Value
Total, fair value	94,469	99,941
Recurring fair value measurements \| Residential Passthrough Securities \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Residential Collateralized Mortgage Obligations
Assets Measured at Fair Value
Total, fair value	33,397	40,296
Recurring fair value measurements \| Residential Collateralized Mortgage Obligations \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Residential Collateralized Mortgage Obligations \| Level 2
Assets Measured at Fair Value
Total, fair value	33,397	40,296
Recurring fair value measurements \| Residential Collateralized Mortgage Obligations \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Commercial Mortgage Backed Securities
Assets Measured at Fair Value
Total, fair value	63,672	79,686
Recurring fair value measurements \| Commercial Mortgage Backed Securities \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Commercial Mortgage Backed Securities \| Level 2
Assets Measured at Fair Value
Total, fair value	63,672	79,686
Recurring fair value measurements \| Commercial Mortgage Backed Securities \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Private label commercial mortgage-backed securities
Assets Measured at Fair Value
Total, fair value	8,026	8,023
Recurring fair value measurements \| Private label commercial mortgage-backed securities \| Level 1
Assets Measured at Fair Value
Total, fair value	0	0
Recurring fair value measurements \| Private label commercial mortgage-backed securities \| Level 2
Assets Measured at Fair Value
Total, fair value	8,026	8,023
Recurring fair value measurements \| Private label commercial mortgage-backed securities \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Nonrecurring fair value measurements
Assets Measured at Fair Value
Total asset fair value measurements	7,674	3,282
Impaired loans, net		3,007
Loans individually evaluated for credit loss, net	7,041
Foreclosed assets held for sale	633	275
Nonrecurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total asset fair value measurements	0	0
Impaired loans, net		0
Loans individually evaluated for credit loss, net	0
Foreclosed assets held for sale	0	0
Nonrecurring fair value measurements \| Level 2
Assets Measured at Fair Value
Total asset fair value measurements	0	0
Impaired loans, net		0
Loans individually evaluated for credit loss, net	0
Foreclosed assets held for sale	0	0
Nonrecurring fair value measurements \| Level 3
Assets Measured at Fair Value
Total asset fair value measurements	7,674	3,282
Impaired loans, net		3,007
Loans individually evaluated for credit loss, net	7,041
Foreclosed assets held for sale	$ 633	$ 275

Fair value disclosure of financing receivables that were individually evaluated for impairment.

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