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LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Finance receivable by credit quality indicator [Abstract]
Loans	$ 1,324,220	$ 1,312,903
Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	422,232	428,037
Pass
Finance receivable by credit quality indicator [Abstract]
Loans	845,956	826,396
Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	17,733	18,534
Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	28,163	29,701
Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	10,136	10,235
Commercial and agricultural
Finance receivable by credit quality indicator [Abstract]
Loans	236,650	230,922
Commercial Mortgages
Finance receivable by credit quality indicator [Abstract]
Loans	661,661	650,570
Commercial Mortgages | Construction
Finance receivable by credit quality indicator [Abstract]
Loans	41,073	44,082
Commercial Mortgages | Construction | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial Mortgages | Construction | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	37,123	40,304
Commercial Mortgages | Construction | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	398	168
Commercial Mortgages | Construction | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	3,552	3,610
Commercial Mortgages | Construction | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial Mortgages | Commercial mortgages
Finance receivable by credit quality indicator [Abstract]
Loans	620,588	606,488
Commercial Mortgages | Commercial mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial Mortgages | Commercial mortgages | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	593,742	577,266
Commercial Mortgages | Commercial mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	11,483	12,451
Commercial Mortgages | Commercial mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	11,008	12,356
Commercial Mortgages | Commercial mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	4,355	4,415
Residential mortgages
Finance receivable by credit quality indicator [Abstract]
Loans	193,269	188,874
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	193,269	188,874
Residential mortgages | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	191,004	186,719
Residential mortgages | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	2,265	2,155
Residential mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	191,004	186,719
Residential mortgages | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Residential mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Residential mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	2,265	2,155
Residential mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans
Finance receivable by credit quality indicator [Abstract]
Loans	232,640	242,537
Consumer Loans | Credit cards
Finance receivable by credit quality indicator [Abstract]
Loans		0
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	0	0
Consumer Loans | Credit cards | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	0	0
Consumer Loans | Credit cards | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	0	0
Consumer Loans | Credit cards | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Credit cards | Pass
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Credit cards | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Credit cards | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Credit cards | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Home equity lines and loans
Finance receivable by credit quality indicator [Abstract]
Loans	88,421	92,065
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	88,421	92,065
Consumer Loans | Home equity lines and loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	87,783	91,424
Consumer Loans | Home equity lines and loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	638	641
Consumer Loans | Home equity lines and loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	87,783	91,424
Consumer Loans | Home equity lines and loans | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Home equity lines and loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Home equity lines and loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	638	641
Consumer Loans | Home equity lines and loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Indirect consumer loans
Finance receivable by credit quality indicator [Abstract]
Loans	129,809	135,366
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	129,809	135,366
Consumer Loans | Indirect consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	129,042	134,795
Consumer Loans | Indirect consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	767	571
Consumer Loans | Indirect consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	129,042	134,795
Consumer Loans | Indirect consumer loans | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Indirect consumer loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Indirect consumer loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	767	571
Consumer Loans | Indirect consumer loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Direct consumer loans
Finance receivable by credit quality indicator [Abstract]
Loans	14,410	15,106
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	14,410	15,106
Consumer Loans | Direct consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	14,403	15,099
Consumer Loans | Direct consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	7	7
Consumer Loans | Direct consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	14,403	15,099
Consumer Loans | Direct consumer loans | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Direct consumer loans | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Direct consumer loans | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	7	7
Consumer Loans | Direct consumer loans | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial and industrial | Commercial and agricultural
Finance receivable by credit quality indicator [Abstract]
Loans	236,360	230,648
Commercial and industrial | Commercial and agricultural | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial and industrial | Commercial and agricultural | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	214,801	208,552
Commercial and industrial | Commercial and agricultural | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	5,852	5,915
Commercial and industrial | Commercial and agricultural | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	9,926	10,361
Commercial and industrial | Commercial and agricultural | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	5,781	5,820
Agricultural | Commercial and agricultural
Finance receivable by credit quality indicator [Abstract]
Loans	290	274
Agricultural | Commercial and agricultural | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Agricultural | Commercial and agricultural | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	290	274
Agricultural | Commercial and agricultural | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Agricultural | Commercial and agricultural | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Agricultural | Commercial and agricultural | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	$ 0	$ 0

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Amount, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 45
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