LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowances (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	$ 15,104	$ 14,668	$ 14,253	$ 14,260
Charge-offs	(816)	(443)	(1,708)	(1,233)
Recoveries	117	50	399	265
Net recoveries (charge-offs)	(699)	(393)	(1,309)	(968)
Provision	1,289	1,050	2,750	2,033
Ending balance	15,694	15,325	15,694	15,325
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					$ 1,168	$ 876
Collectively evaluated for impairment					14,497	13,293
Total ending allowance balance	15,104	14,668	14,253	14,260	15,694	14,253
Loans [Abstract]
Loans individually evaluated for impairment					11,092	11,926
Loans collectively evaluated for impairment					1,280,337	1,190,138
Total ending loans balance					1,292,261	1,203,482
Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			84
Ending balance	29		29
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	29		84		29	84
Loans [Abstract]
Total ending loans balance					832	1,418
Commercial and agricultural:
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	1,883	1,771	1,589	1,831
Charge-offs	(89)	(104)	(96)	(121)
Recoveries	34	15	95	65
Net recoveries (charge-offs)	(55)	(89)	(1)	(56)
Provision	99	101	339	8
Ending balance	1,927	1,783	1,927	1,783
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					159	0
Collectively evaluated for impairment					1,768	1,589
Total ending allowance balance	1,883	1,771	1,589	1,831	1,927	1,589
Loans [Abstract]
Loans individually evaluated for impairment					1,133	693
Loans collectively evaluated for impairment					188,170	176,334
Total ending loans balance					189,303	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	7,778	7,754	7,270	7,112
Charge-offs	(154)	(52)	(154)	(52)
Recoveries	1	1	4	10
Net recoveries (charge-offs)	(153)	(51)	(150)	(42)
Provision	758	520	1,263	1,153
Ending balance	8,383	8,223	8,383	8,223
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					1,009	735
Collectively evaluated for impairment					7,345	6,476
Total ending allowance balance	7,778	7,754	7,270	7,112	8,383	7,270
Loans [Abstract]
Loans individually evaluated for impairment					9,458	10,382
Loans collectively evaluated for impairment					629,211	558,451
Total ending loans balance					639,501	570,156
Commercial Mortgages | Loans acquired with deteriorated credit quality
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance			59
Ending balance	29		29
Ending allowance balance attributable to loans [Abstract]
Total ending allowance balance	29		59		29	59
Loans [Abstract]
Total ending loans balance					832	1,323
Residential mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	1,517	1,504	1,523	1,464
Charge-offs	(133)	(7)	(193)	(65)
Recoveries	0	0	30	0
Net recoveries (charge-offs)	(133)	(7)	(163)	(65)
Provision	12	50	36	148
Ending balance	1,396	1,547	1,396	1,547
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					0	0
Collectively evaluated for impairment					1,396	1,498
Total ending allowance balance	1,517	1,504	1,523	1,464	1,396	1,523
Loans [Abstract]
Loans individually evaluated for impairment					434	396
Loans collectively evaluated for impairment					197,267	198,474
Total ending loans balance					197,701	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	3,926	3,639	3,871	3,853
Charge-offs	(440)	(280)	(1,265)	(995)
Recoveries	82	34	270	190
Net recoveries (charge-offs)	(358)	(246)	(995)	(805)
Provision	420	379	1,112	724
Ending balance	3,988	3,772	3,988	3,772
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment					0	141
Collectively evaluated for impairment					3,988	3,730
Total ending allowance balance	3,926	$ 3,639	3,871	$ 3,853	3,988	3,871
Loans [Abstract]
Loans individually evaluated for impairment					67	455
Loans collectively evaluated for impairment					265,689	256,879
Total ending loans balance					265,756	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