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LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	$ 1,585,984	$ 1,541,498
Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	451,361	448,787
Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,079,053	1,036,759
Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	24,734	26,630
Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	28,450	26,813
Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	2,386	2,509
Commercial and agricultural:
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	400,719	370,252
Commercial and agricultural: | Commercial and industrial
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	400,281	369,968
Commercial and agricultural: | Commercial and industrial | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial and agricultural: | Commercial and industrial | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	390,138	360,500
Commercial and agricultural: | Commercial and industrial | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	3,232	2,999
Commercial and agricultural: | Commercial and industrial | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	5,652	5,092
Commercial and agricultural: | Commercial and industrial | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,259	1,377
Commercial and agricultural: | Agricultural
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	438	284
Commercial and agricultural: | Agricultural | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial and agricultural: | Agricultural | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	438	284
Commercial and agricultural: | Agricultural | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial and agricultural: | Agricultural | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial and agricultural: | Agricultural | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial mortgages:
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	731,438	719,145
Commercial mortgages: | Construction
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	58,525	62,164
Commercial mortgages: | Construction | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial mortgages: | Construction | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	57,131	59,885
Commercial mortgages: | Construction | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial mortgages: | Construction | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,394	2,279
Commercial mortgages: | Construction | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial mortgages: | Commercial mortgages
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	672,913	656,981
Commercial mortgages: | Commercial mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Commercial mortgages: | Commercial mortgages | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	631,346	616,090
Commercial mortgages: | Commercial mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	21,502	23,631
Commercial mortgages: | Commercial mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	18,938	16,128
Commercial mortgages: | Commercial mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,127	1,132
Residential mortgages
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	245,843	240,013
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	245,843	240,013
Residential mortgages | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	244,589	238,381
Residential mortgages | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	1,254	1,632
Residential mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	244,589	238,381
Residential mortgages | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Residential mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Residential mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,254	1,632
Residential mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans:
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	207,984	212,088
Consumer loans: | Home equity lines and loans
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	75,081	78,761
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	75,081	78,761
Consumer loans: | Home equity lines and loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	74,408	77,602
Consumer loans: | Home equity lines and loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	673	1,159
Consumer loans: | Home equity lines and loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	74,408	77,602
Consumer loans: | Home equity lines and loans | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Home equity lines and loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Home equity lines and loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	673	1,159
Consumer loans: | Home equity lines and loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Indirect consumer loans
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	121,197	120,853
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	121,197	120,853
Consumer loans: | Indirect consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	120,676	120,334
Consumer loans: | Indirect consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	521	519
Consumer loans: | Indirect consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	120,676	120,334
Consumer loans: | Indirect consumer loans | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Indirect consumer loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Indirect consumer loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	521	519
Consumer loans: | Indirect consumer loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Direct consumer loans
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	11,706	12,474
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	11,706	12,474
Consumer loans: | Direct consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	11,688	12,470
Consumer loans: | Direct consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	18	4
Consumer loans: | Direct consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	11,688	12,470
Consumer loans: | Direct consumer loans | Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Direct consumer loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Direct consumer loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	18	4
Consumer loans: | Direct consumer loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	$ 0	$ 0

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