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LOANS AND ALLOWANCE FOR LOAN LOSSES - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Unpaid Principal Balance
Total	$ 13,081		$ 18,205
Recorded Investment
Total	10,403		11,647
Allowance for Loan Losses Allocated	2,861		3,030
Average Recorded Investment
Average recorded investment, total	11,023	$ 10,257
Interest Income Recognized
Total	47	35
Residential Mortgages
Unpaid Principal Balance
With no related allowance recorded	943		951
Recorded Investment
With no related allowance recorded	931		938
Average Recorded Investment
With no related allowance recorded	934	1,118
Interest Income Recognized
With no related allowance recorded	11	8
Construction | Commercial Mortgages
Unpaid Principal Balance
With no related allowance recorded	112		129
Recorded Investment
With no related allowance recorded	113		130
Average Recorded Investment
With no related allowance recorded	121	182
Interest Income Recognized
With no related allowance recorded	1	2
Commercial mortgages, other | Commercial Mortgages
Unpaid Principal Balance
With no related allowance recorded	6,768		6,940
With an allowance recorded	2,601		3,550
Recorded Investment
With no related allowance recorded	4,107		4,278
With an allowance recorded	2,609		3,559
Allowance for Loan Losses Allocated	1,479		1,571
Average Recorded Investment
With no related allowance recorded	4,193	4,822
With an allowance recorded	3,084	167
Interest Income Recognized
With no related allowance recorded	7	8
With an allowance recorded	21	0
Home equity lines and loans | Consumer Loans
Unpaid Principal Balance
With no related allowance recorded	177		185
With an allowance recorded	141		146
Recorded Investment
With no related allowance recorded	161		169
With an allowance recorded	141		146
Allowance for Loan Losses Allocated	53		65
Average Recorded Investment
With no related allowance recorded	165	413
With an allowance recorded	143	166
Interest Income Recognized
With no related allowance recorded	1	2
With an allowance recorded	0	0
Commercial and industrial | Commercial and Agricultural
Unpaid Principal Balance
With no related allowance recorded	927		954
With an allowance recorded	1,412		5,350
Recorded Investment
With no related allowance recorded	927		948
With an allowance recorded	1,414		1,479
Allowance for Loan Losses Allocated	1,329		$ 1,394
Average Recorded Investment
With no related allowance recorded	937	1,912
With an allowance recorded	1,446	1,477
Interest Income Recognized
With no related allowance recorded	3	13
With an allowance recorded	$ 3	$ 2

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