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LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2016	Dec. 31, 2015
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	$ 14,260	$ 13,686	$ 12,776
Charge Offs	(2,830)	(1,631)	(4,278)
Recoveries	386	634	1,207
Net (charge offs) recoveries	(2,444)	(997)	(3,071)
Provision	2,437	1,571	3,981
Ending balance	14,253	14,260	13,686
Ending allowance balance attributable to loans:
Individually evaluated for impairment				$ 876	$ 1,566
Collectively evaluated for impairment				13,293	12,595
Allowance for loan losses	14,260	13,686	12,776	14,253	14,260
Loans:
Loans individually evaluated for impairment				11,926	14,980
Loans collectively evaluated for impairment				1,190,138	1,154,428
Total ending loans balance				1,203,482	1,171,503
Commercial, and Agricultural
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	1,831	1,460	1,979
Charge Offs	(217)	(186)	(444)
Recoveries	92	96	385
Net (charge offs) recoveries	(125)	(90)	(59)
Provision	(117)	461	(460)
Ending balance	1,589	1,831	1,460
Ending allowance balance attributable to loans:
Individually evaluated for impairment				0	8
Collectively evaluated for impairment				1,589	1,823
Allowance for loan losses	1,831	1,460	1,979	1,589	1,831
Loans:
Loans individually evaluated for impairment				693	1,498
Loans collectively evaluated for impairment				176,334	192,202
Total ending loans balance				177,027	193,700
Commercial mortgages:
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	7,112	6,326	6,243
Charge Offs	(911)	(104)	(2,229)
Recoveries	10	131	156
Net (charge offs) recoveries	(901)	27	(2,073)
Provision	1,059	759	2,156
Ending balance	7,270	7,112	6,326
Ending allowance balance attributable to loans:
Individually evaluated for impairment				735	1,481
Collectively evaluated for impairment				6,476	5,572
Allowance for loan losses	7,112	6,326	6,243	7,270	7,112
Loans:
Loans individually evaluated for impairment				10,382	12,773
Loans collectively evaluated for impairment				558,451	493,102
Total ending loans balance				570,156	507,700
Residential Mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	1,464	1,572	1,517
Charge Offs	(65)	(47)	(97)
Recoveries	0	0	32
Net (charge offs) recoveries	(65)	(47)	(65)
Provision	124	(61)	120
Ending balance	1,523	1,464	1,572
Ending allowance balance attributable to loans:
Individually evaluated for impairment				0	0
Collectively evaluated for impairment				1,498	1,424
Allowance for loan losses	1,464	1,572	1,517	1,523	1,464
Loans:
Loans individually evaluated for impairment				396	235
Loans collectively evaluated for impairment				198,474	195,731
Total ending loans balance				198,965	196,236
Consumer Loans
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	3,853	4,328	3,037
Charge Offs	(1,637)	(1,294)	(1,508)
Recoveries	284	407	634
Net (charge offs) recoveries	(1,353)	(887)	(874)
Provision	1,371	412	2,165
Ending balance	3,871	3,853	4,328
Ending allowance balance attributable to loans:
Individually evaluated for impairment				141	77
Collectively evaluated for impairment				3,730	3,776
Allowance for loan losses	3,853	4,328	$ 3,037	3,871	3,853
Loans:
Loans individually evaluated for impairment				455	474
Loans collectively evaluated for impairment				256,879	273,393
Total ending loans balance				257,334	273,867
Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	99
Ending balance	84	99
Ending allowance balance attributable to loans:
Allowance for loan losses	99	99		84	99
Loans:
Total ending loans balance				1,418	2,095
Loans acquired with deteriorated credit quality | Commercial, and Agricultural
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	0
Ending balance	0	0
Ending allowance balance attributable to loans:
Allowance for loan losses	0	0		0	0
Loans:
Total ending loans balance				0	0
Loans acquired with deteriorated credit quality | Commercial mortgages:
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	59
Ending balance	59	59
Ending allowance balance attributable to loans:
Allowance for loan losses	59	59		59	59
Loans:
Total ending loans balance				1,323	1,825
Loans acquired with deteriorated credit quality | Residential Mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	40
Ending balance	25	40
Ending allowance balance attributable to loans:
Allowance for loan losses	40	40		25	40
Loans:
Total ending loans balance				95	270
Loans acquired with deteriorated credit quality | Consumer Loans
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance:	0
Ending balance	0	0
Ending allowance balance attributable to loans:
Allowance for loan losses	$ 0	$ 0		0	0
Loans:
Total ending loans balance				$ 0	$ 0

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