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FAIR VALUE MEASUREMENTS AND FAIR VALUES OF FINANCIAL INSTRUMENTS - Assets Measured at Fair Value (Details) - USD ($)	Dec. 31, 2020	Jul. 01, 2020	Dec. 31, 2019
Assets Measured at Fair Value
Total, fair value	$ 349,332,000		$ 346,723,000
Marketable equity security	1,000,000		979,000
Fair value derivative asset		$ 7,932,000
Fair value of the derivative liability		$ 7,932,000
Impaired loans with a valuation allowance	8,082,000		3,375,000
Valuation allowance	(925,000)		(1,051,000)
Impaired loans, net	8,082,000		3,375,000
Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	6,566,000
Fair value of the derivative liability	6,566,000
Obligations of the U.S. Treasury
Assets Measured at Fair Value
Total, fair value	12,182,000
Obligations of U.S. Government agencies
Assets Measured at Fair Value
Total, fair value	26,344,000		17,000,000
Obligations of U.S. Government agencies \| Level 1
Assets Measured at Fair Value
Total, fair value	0
Obligations of U.S. Government agencies \| Level 2
Assets Measured at Fair Value
Total, fair value	26,344,000
Obligations of U.S. Government agencies \| Level 3
Assets Measured at Fair Value
Total, fair value	0
Obligations Of States And Political Subdivisions Tax Exempt
Assets Measured at Fair Value
Total, fair value	122,401,000		70,760,000
Obligations Of States And Political Subdivisions Taxable
Assets Measured at Fair Value
Total, fair value	47,452,000		36,303,000
Residential Passthrough Securities
Assets Measured at Fair Value
Total, fair value	38,176,000		59,210,000
Residential Collateralized Mortgage Obligations
Assets Measured at Fair Value
Total, fair value	57,467,000		114,723,000
Commercial Mortgage Backed Securities
Assets Measured at Fair Value
Total, fair value	45,310,000		48,727,000
Recurring fair value measurements
Assets Measured at Fair Value
Total, fair value	349,332,000		346,723,000
Marketable equity security	1,000,000		979,000
Servicing rights	1,689,000		1,277,000
Total asset fair value measurements	358,587,000		348,979,000
Recurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total, fair value	0		0
Marketable equity security	1,000,000		979,000
Servicing rights	0		0
Total asset fair value measurements	1,000,000		979,000
Recurring fair value measurements \| Level 2
Assets Measured at Fair Value
Total, fair value	349,332,000		346,723,000
Marketable equity security	0		0
Servicing rights	0		0
Total asset fair value measurements	355,898,000		346,723,000
Recurring fair value measurements \| Level 3
Assets Measured at Fair Value
Total, fair value	0		0
Marketable equity security	0		0
Servicing rights	1,689,000		1,277,000
Total asset fair value measurements	1,689,000		1,277,000
Recurring fair value measurements \| Interest rate swap agreements
Assets Measured at Fair Value
Fair value derivative asset	6,566,000
Fair value of the derivative liability	6,566,000
Recurring fair value measurements \| Interest rate swap agreements \| Level 1
Assets Measured at Fair Value
Fair value derivative asset	0
Fair value of the derivative liability	0
Recurring fair value measurements \| Interest rate swap agreements \| Level 2
Assets Measured at Fair Value
Fair value derivative asset	6,566,000
Fair value of the derivative liability	6,566,000
Recurring fair value measurements \| Interest rate swap agreements \| Level 3
Assets Measured at Fair Value
Fair value derivative asset	0
Fair value of the derivative liability	0
Recurring fair value measurements \| Obligations of the U.S. Treasury
Assets Measured at Fair Value
Total, fair value	12,182,000
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 1
Assets Measured at Fair Value
Total, fair value	0
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 2
Assets Measured at Fair Value
Total, fair value	12,182,000
Recurring fair value measurements \| Obligations of the U.S. Treasury \| Level 3
Assets Measured at Fair Value
Total, fair value	0
Recurring fair value measurements \| Obligations of U.S. Government agencies
Assets Measured at Fair Value
Total, fair value			17,000,000
Recurring fair value measurements \| Obligations of U.S. Government agencies \| Level 1
Assets Measured at Fair Value
Total, fair value			0
Recurring fair value measurements \| Obligations of U.S. Government agencies \| Level 2
Assets Measured at Fair Value
Total, fair value			17,000,000
Recurring fair value measurements \| Obligations of U.S. Government agencies \| 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	122,401,000		70,760,000
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	122,401,000		70,760,000
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	47,452,000		36,303,000
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	47,452,000		36,303,000
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	38,176,000		59,210,000
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	38,176,000		59,210,000
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	57,467,000		114,723,000
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	57,467,000		114,723,000
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	45,310,000		48,727,000
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	45,310,000		48,727,000
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	8,495,000		5,210,000
Impaired loans with a valuation allowance	8,082,000		3,375,000
Valuation allowance	(925,000)		(1,051,000)
Impaired loans, net	7,157,000		2,324,000
Foreclosed assets held for sale	1,338,000		2,886,000
Nonrecurring fair value measurements \| Level 1
Assets Measured at Fair Value
Total asset fair value measurements	0		0
Impaired loans with a valuation allowance	0		0
Valuation allowance	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 with a valuation allowance	0		0
Valuation allowance	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	8,495,000		5,210,000
Impaired loans with a valuation allowance	8,082,000		3,375,000
Valuation allowance	(925,000)		(1,051,000)
Impaired loans, net	7,157,000		2,324,000
Foreclosed assets held for sale	$ 1,338,000		$ 2,886,000