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LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowances (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	$ 14,960	$ 14,527	$ 14,253	$ 14,260
Charge-offs	(447)	(339)	(892)	(790)
Recoveries	170	92	282	215
Net recoveries (charge-offs)	(277)	(247)	(610)	(575)
Provision	421	388	1,461	983
Ending balance	15,104	14,668	15,104	14,668
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					$ 970	$ 876
Collectively evaluated for impairment					14,104	13,293
Total ending allowance balance	14,960	14,527	14,253	14,260	15,104	14,253
Loans [Abstract]
Loans individually evaluated for impairment					13,108	11,926
Loans collectively evaluated for impairment					1,241,682	1,190,138
Total ending loans balance					1,255,796	1,203,482
Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			84
Ending balance	30		30
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	30		84		30	84
Loans [Abstract]
Total ending loans balance					1,006	1,418
Commercial and agricultural:
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	1,650	1,795	1,589	1,831
Charge-offs	(2)	(9)	(7)	(17)
Recoveries	36	18	61	50
Net recoveries (charge-offs)	34	9	54	33
Provision	199	(33)	240	(93)
Ending balance	1,883	1,771	1,883	1,771
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					84	0
Collectively evaluated for impairment					1,799	1,589
Total ending allowance balance	1,650	1,795	1,589	1,831	1,883	1,589
Loans [Abstract]
Loans individually evaluated for impairment					772	693
Loans collectively evaluated for impairment					189,167	176,334
Total ending loans balance					189,939	177,027
Commercial and agricultural: | Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			0
Ending balance	0		0
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	0		0		0	0
Loans [Abstract]
Total ending loans balance					0	0
Commercial Mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	7,749	7,532	7,270	7,112
Charge-offs	0	0	0	0
Recoveries	2	2	3	9
Net recoveries (charge-offs)	2	2	3	9
Provision	27	220	505	633
Ending balance	7,778	7,754	7,778	7,754
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					886	735
Collectively evaluated for impairment					6,862	6,476
Total ending allowance balance	7,749	7,532	7,270	7,112	7,778	7,270
Loans [Abstract]
Loans individually evaluated for impairment					11,823	10,382
Loans collectively evaluated for impairment					593,413	558,451
Total ending loans balance					606,242	570,156
Commercial Mortgages | Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			59
Ending balance	30		30
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	30		59		30	59
Loans [Abstract]
Total ending loans balance					1,006	1,323
Residential mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	1,512	1,482	1,523	1,464
Charge-offs	(48)	(58)	(60)	(58)
Recoveries	13	0	30	0
Net recoveries (charge-offs)	(35)	(58)	(30)	(58)
Provision	40	80	24	98
Ending balance	1,517	1,504	1,517	1,504
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					0	0
Collectively evaluated for impairment					1,517	1,498
Total ending allowance balance	1,512	1,482	1,523	1,464	1,517	1,523
Loans [Abstract]
Loans individually evaluated for impairment					443	396
Loans collectively evaluated for impairment					200,674	198,474
Total ending loans balance					201,117	198,965
Residential mortgages | Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			25
Ending balance	0		0
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	0		25		0	25
Loans [Abstract]
Total ending loans balance					0	95
Consumer loans:
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	4,049	3,718	3,871	3,853
Charge-offs	(397)	(272)	(825)	(715)
Recoveries	119	72	188	156
Net recoveries (charge-offs)	(278)	(200)	(637)	(559)
Provision	155	121	692	345
Ending balance	3,926	3,639	3,926	3,639
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					0	141
Collectively evaluated for impairment					3,926	3,730
Total ending allowance balance	4,049	$ 3,718	3,871	$ 3,853	3,926	3,871
Loans [Abstract]
Loans individually evaluated for impairment					70	455
Loans collectively evaluated for impairment					258,428	256,879
Total ending loans balance					258,498	257,334
Consumer loans: | Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			0
Ending balance	0		0
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	$ 0		$ 0		0	0
Loans [Abstract]
Total ending loans balance					$ 0	$ 0

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