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LOANS AND ALLOWANCE FOR LOAN LOSSES - Credit Quality Indicator (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Finance receivable by credit quality indicator [Abstract]
Loans	$ 1,324,522	$ 1,315,582
Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	792
Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	459,399	464,414
Pass
Finance receivable by credit quality indicator [Abstract]
Loans	822,903	807,976
Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	20,214	14,112
Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	18,978	25,489
Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	3,028	2,799
Commercial and agricultural
Finance receivable by credit quality indicator [Abstract]
Loans	192,958	199,576
Commercial and agricultural | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans		0
Commercial Mortgages
Finance receivable by credit quality indicator [Abstract]
Loans	667,575	646,174
Commercial Mortgages | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans		792
Commercial Mortgages | Construction
Finance receivable by credit quality indicator [Abstract]
Loans	50,504	45,688
Commercial Mortgages | Construction | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
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	50,389	45,553
Commercial Mortgages | Construction | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Commercial Mortgages | Construction | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	115	135
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	617,071	600,486
Commercial Mortgages | Commercial mortgages | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	792
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	592,724	575,321
Commercial Mortgages | Commercial mortgages | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	10,793	9,665
Commercial Mortgages | Commercial mortgages | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	12,252	13,331
Commercial Mortgages | Commercial mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	1,302	1,377
Residential mortgages
Finance receivable by credit quality indicator [Abstract]
Loans	189,161	194,937
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	189,161	194,937
Residential mortgages | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Residential mortgages | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	186,507	191,777
Residential mortgages | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	2,654	3,160
Residential mortgages | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	186,507	191,777
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	2,654	3,160
Residential mortgages | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans
Finance receivable by credit quality indicator [Abstract]
Loans	274,828	274,895
Consumer Loans | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans		0
Consumer Loans | Credit cards
Finance receivable by credit quality indicator [Abstract]
Loans	1,393	1,516
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	1,393	1,516
Consumer Loans | Credit cards | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Credit cards | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	1,393	1,516
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	1,393	1,516
Consumer Loans | Credit cards | Pass
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Credit cards | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Credit cards | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Credit cards | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Home equity lines and loans
Finance receivable by credit quality indicator [Abstract]
Loans	98,537	100,878
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	98,537	100,878
Consumer Loans | Home equity lines and loans | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Home equity lines and loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	97,248	99,568
Consumer Loans | Home equity lines and loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	1,289	1,310
Consumer Loans | Home equity lines and loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	97,248	99,568
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	1,289	1,310
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	157,526	153,532
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	157,526	153,532
Consumer Loans | Indirect consumer loans | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Indirect consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	156,910	152,598
Consumer Loans | Indirect consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	616	934
Consumer Loans | Indirect consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	156,910	152,598
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	616	934
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	17,372	18,969
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	17,372	18,969
Consumer Loans | Direct consumer loans | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
Consumer Loans | Direct consumer loans | Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	17,341	18,955
Consumer Loans | Direct consumer loans | Non-Performing
Residential and consumer finance receivable [Abstract]
Residential and consumer loans receivable	31	14
Consumer Loans | Direct consumer loans | Not Rated
Finance receivable by credit quality indicator [Abstract]
Loans	17,341	18,955
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	31	14
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	192,670	199,030
Commercial and industrial | Commercial and agricultural | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
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	179,502	186,556
Commercial and industrial | Commercial and agricultural | Special Mention
Finance receivable by credit quality indicator [Abstract]
Loans	9,421	4,447
Commercial and industrial | Commercial and agricultural | Substandard
Finance receivable by credit quality indicator [Abstract]
Loans	2,021	6,605
Commercial and industrial | Commercial and agricultural | Doubtful
Finance receivable by credit quality indicator [Abstract]
Loans	1,726	1,422
Agricultural | Commercial and agricultural
Finance receivable by credit quality indicator [Abstract]
Loans	288	546
Agricultural | Commercial and agricultural | Loans acquired with deteriorated credit quality
Finance receivable by credit quality indicator [Abstract]
Loans	0	0
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	288	546
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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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