FAIR VALUE MEASUREMENTS AND FAIR VALUES OF FINANCIAL INSTRUMENTS - Assets Measured at Fair Value (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Assets Measured at Fair Value
Total, fair value	$ 517,679,000	$ 349,332,000
Marketable equity security	971,000	1,000,000
Impaired loans with a valuation allowance	6,540,000	8,082,000
Valuation allowance	(740,000)	(925,000)
Impaired loans, net	6,540,000	8,082,000
Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	3,104,000	6,566,000
Fair value of the derivative liability	3,104,000	6,566,000
Obligations of the U.S. Treasury
Assets Measured at Fair Value
Total, fair value	24,912,000	12,182,000
Obligations of U.S. Government agencies
Assets Measured at Fair Value
Total, fair value	24,091,000	26,344,000
Bank holding company debt securities
Assets Measured at Fair Value
Total, fair value	17,987,000
Obligations Of States And Political Subdivisions Tax Exempt
Assets Measured at Fair Value
Total, fair value	148,028,000	122,401,000
Obligations Of States And Political Subdivisions Taxable
Assets Measured at Fair Value
Total, fair value	72,765,000	47,452,000
Residential Passthrough Securities
Assets Measured at Fair Value
Total, fair value	98,181,000	38,176,000
Residential Collateralized Mortgage Obligations
Assets Measured at Fair Value
Total, fair value	44,247,000	57,467,000
Commercial Mortgage Backed Securities
Assets Measured at Fair Value
Total, fair value	87,468,000	45,310,000
Recurring fair value measurements
Assets Measured at Fair Value
Total, fair value	517,679,000	349,332,000
Marketable equity security	971,000	1,000,000
Servicing rights	2,329,000	1,689,000
Total asset fair value measurements	524,083,000	358,587,000
Recurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total, fair value	24,912,000	12,182,000
Marketable equity security	971,000	1,000,000
Servicing rights	0	0
Total asset fair value measurements	25,883,000	13,182,000
Recurring fair value measurements \| Level 2
Assets Measured at Fair Value
Total, fair value	492,767,000	337,150,000
Marketable equity security	0	0
Servicing rights	0	0
Total asset fair value measurements	495,871,000	343,716,000
Recurring fair value measurements \| Level 3
Assets Measured at Fair Value
Total, fair value	0	0
Marketable equity security	0	0
Servicing rights	2,329,000	1,689,000
Total asset fair value measurements	2,329,000	1,689,000
Recurring fair value measurements \| Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	3,104,000	6,566,000
Fair value of the derivative liability	3,104,000	6,566,000
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	3,104,000	6,566,000
Fair value of the derivative liability	3,104,000	6,566,000
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	24,912,000	12,182,000
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 1
Assets Measured at Fair Value
Total, fair value	24,912,000	12,182,000
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	24,091,000	26,344,000
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	24,091,000	26,344,000
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	17,987,000
Recurring fair value measurements \| Bank holding company debt securities \| Level 1
Assets Measured at Fair Value
Total, fair value	0
Recurring fair value measurements \| Bank holding company debt securities \| Level 2
Assets Measured at Fair Value
Total, fair value	17,987,000
Recurring fair value measurements \| Bank holding company debt securities \| Level 3
Assets Measured at Fair Value
Total, fair value	0
Recurring fair value measurements \| Obligations Of States And Political Subdivisions Tax Exempt
Assets Measured at Fair Value
Total, fair value	148,028,000	122,401,000
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	148,028,000	122,401,000
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	72,765,000	47,452,000
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	72,765,000	47,452,000
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	98,181,000	38,176,000
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	98,181,000	38,176,000
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	44,247,000	57,467,000
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	44,247,000	57,467,000
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	87,468,000	45,310,000
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	87,468,000	45,310,000
Recurring fair value measurements \| 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	6,484,000	8,495,000
Impaired loans, net	5,800,000	7,157,000
Foreclosed assets held for sale	684,000	1,338,000
Nonrecurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total asset fair value measurements	0	0
Impaired loans, net	0	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	0
Foreclosed assets held for sale	0	0
Nonrecurring fair value measurements \| Level 3
Assets Measured at Fair Value
Total asset fair value measurements	6,484,000	8,495,000
Impaired loans, net	5,800,000	7,157,000
Foreclosed assets held for sale	$ 684,000	$ 1,338,000

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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