LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	$ 1,562,822	$ 1,541,498
Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	451,610	448,787
Pass
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,059,362	1,036,759
Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	26,424	26,630
Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	23,080	26,813
Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	2,346	2,509
Commercial and agricultural:
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	341,994	370,252
Commercial and agricultural: | Commercial and industrial
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	341,572	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	332,300	360,500
Commercial and agricultural: | Commercial and industrial | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	3,529	2,999
Commercial and agricultural: | Commercial and industrial | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	4,523	5,092
Commercial and agricultural: | Commercial and industrial | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,220	1,377
Commercial and agricultural: | Agricultural
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	422	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	422	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	767,200	719,145
Commercial mortgages: | Construction
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	67,968	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	67,209	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	759	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	699,232	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	659,431	616,090
Commercial mortgages: | Commercial mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	22,895	23,631
Commercial mortgages: | Commercial mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	15,780	16,128
Commercial mortgages: | Commercial mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	1,126	1,132
Residential mortgages
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	247,309	240,013
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	247,310	240,013
Residential mortgages | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	246,394	238,381
Residential mortgages | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	916	1,632
Residential mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	246,393	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	916	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	206,319	212,088
Consumer loans: | Home equity lines and loans
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	74,309	78,761
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	74,309	78,761
Consumer loans: | Home equity lines and loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	73,539	77,602
Consumer loans: | Home equity lines and loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	770	1,159
Consumer loans: | Home equity lines and loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	73,539	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	770	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	120,895	120,853
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	120,894	120,853
Consumer loans: | Indirect consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	120,576	120,334
Consumer loans: | Indirect consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	318	519
Consumer loans: | Indirect consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	120,577	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	318	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	11,115	12,474
Consumer loans: | Direct consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	11,101	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	14	4
Consumer loans: | Direct consumer loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Total ending loans balance	0	0
Consumer loans: | Other Direct Consumer Loans
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	11,115	12,474
Consumer loans: | Other Direct Consumer Loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	11,101	12,470
Consumer loans: | Other Direct Consumer Loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	$ 14	$ 4