LOANS, ALLOWANCE FOR LOAN LOSSES, AND CREDIT QUALITY - Summary of changes in ALLL by portfolio segment for periods - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Allowance for Credit Losses
Beginning balance	$ 12,653	$ 11,820	$ 10,307
Provision for loan losses	1,600	2,325	1,800
Charge-offs	(1,213)	(1,604)	(584)
Recoveries	113	112	297
Net charge-offs	(1,100)	(1,492)	(287)
Ending balance	$ 13,153	$ 12,653	11,820
As percent of ALLL	100.00%	100.00%
ALLL:
Individually evaluated	$ 0	$ 163
Collectively evaluated	13,153	12,490
Loans:
Individually evaluated	9,939	17,221
Collectively evaluated	2,156,242	2,070,704
Total loans	2,166,181	2,087,925
Loans, net	2,153,028	2,075,272
Owner-occupied commercial real estate (“CRE”)
Loans:
Total loans	441,353	430,043
Retail & other
Financing Receivable, Allowance for Credit Losses
Beginning balance	225	152
Provision for loan losses	267	127
Charge-offs	(204)	(69)
Recoveries	16	15
Net charge-offs	(188)	(54)
Ending balance	$ 304	$ 225	152
As percent of ALLL	2.30%	1.80%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	304	225
Loans:
Individually evaluated	12	12
Collectively evaluated	26,481	22,803
Total loans	26,493	22,815
Loans, net	26,189	22,590
Commercial Portfolio Segment | Commercial & industrial
Financing Receivable, Allowance for Credit Losses
Beginning balance	4,934	3,919
Provision for loan losses	1,107	2,419
Charge-offs	(813)	(1,442)
Recoveries	43	38
Net charge-offs	(770)	(1,404)
Ending balance	$ 5,271	$ 4,934	3,919
As percent of ALLL	40.10%	39.00%
ALLL:
Individually evaluated	$ 0	$ 163
Collectively evaluated	5,271	4,771
Loans:
Individually evaluated	2,927	5,870
Collectively evaluated	681,993	631,467
Total loans	684,920	637,337
Loans, net	679,649	632,403
Commercial Portfolio Segment | Owner-occupied commercial real estate (“CRE”)
Financing Receivable, Allowance for Credit Losses
Beginning balance	2,607	2,867
Provision for loan losses	300	(290)
Charge-offs	(74)	0
Recoveries	14	30
Net charge-offs	(60)	30
Ending balance	$ 2,847	$ 2,607	2,867
As percent of ALLL	21.60%	20.60%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	2,847	2,607
Loans:
Individually evaluated	1,506	1,689
Collectively evaluated	439,847	428,354
Total loans	441,353	430,043
Loans, net	438,506	427,436
Commercial Portfolio Segment | Agricultural (“AG”) production
Financing Receivable, Allowance for Credit Losses
Beginning balance	129	150
Provision for loan losses	(8)	(21)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 121	$ 129	150
As percent of ALLL	0.90%	1.00%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	121	129
Loans:
Individually evaluated	0	0
Collectively evaluated	35,625	35,455
Total loans	35,625	35,455
Loans, net	35,504	35,326
Commercial Real Estate Portfolio Segment | AG real estate
Financing Receivable, Allowance for Credit Losses
Beginning balance	296	285
Provision for loan losses	5	11
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 301	$ 296	285
As percent of ALLL	2.30%	2.30%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	301	296
Loans:
Individually evaluated	222	248
Collectively evaluated	53,222	51,530
Total loans	53,444	51,778
Loans, net	53,143	51,482
Commercial Real Estate Portfolio Segment | CRE investment
Financing Receivable, Allowance for Credit Losses
Beginning balance	1,388	1,124
Provision for loan losses	119	263
Charge-offs	(37)	0
Recoveries	0	1
Net charge-offs	(37)	1
Ending balance	$ 1,470	$ 1,388	1,124
As percent of ALLL	11.20%	11.00%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	1,470	1,388
Loans:
Individually evaluated	1,686	5,290
Collectively evaluated	341,966	309,173
Total loans	343,652	314,463
Loans, net	342,182	313,075
Commercial Real Estate Portfolio Segment | Construction & land development
Financing Receivable, Allowance for Credit Losses
Beginning balance	726	774
Provision for loan losses	(216)	(35)
Charge-offs	0	(13)
Recoveries	0	0
Net charge-offs	0	(13)
Ending balance	$ 510	$ 726	774
As percent of ALLL	3.90%	5.70%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	510	726
Loans:
Individually evaluated	603	1,053
Collectively evaluated	79,996	88,607
Total loans	80,599	89,660
Loans, net	80,089	88,934
Residential | Residential first mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	1,609	1,784
Provision for loan losses	117	(192)
Charge-offs	(85)	(8)
Recoveries	5	25
Net charge-offs	(80)	17
Ending balance	$ 1,646	$ 1,609	1,784
As percent of ALLL	12.50%	12.70%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	1,646	1,609
Loans:
Individually evaluated	2,750	2,801
Collectively evaluated	355,091	360,551
Total loans	357,841	363,352
Loans, net	356,195	361,743
Residential | Residential junior mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	488	461
Provision for loan losses	(51)	96
Charge-offs	0	(72)
Recoveries	35	3
Net charge-offs	35	(69)
Ending balance	$ 472	$ 488	461
As percent of ALLL	3.60%	3.90%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	472	488
Loans:
Individually evaluated	233	178
Collectively evaluated	111,095	105,849
Total loans	111,328	106,027
Loans, net	110,856	105,539
Residential | Residential construction
Financing Receivable, Allowance for Credit Losses
Beginning balance	251	304
Provision for loan losses	(40)	(53)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 211	$ 251	304
As percent of ALLL	1.60%	2.00%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	211	251
Loans:
Individually evaluated	0	80
Collectively evaluated	30,926	36,915
Total loans	30,926	36,995
Loans, net	30,715	36,744
Originated
Financing Receivable, Allowance for Credit Losses
Beginning balance	10,542	9,449
Provision for loan losses	2,014	2,585
Charge-offs	(1,200)	(1,537)
Recoveries	92	45
Net charge-offs	(1,108)	(1,492)
Ending balance	$ 11,448	$ 10,542	9,449
As percent of ALLL	100.00%	100.00%
ALLL:
Individually evaluated	$ 0	$ 163
Collectively evaluated	11,448	10,379
Loans:
Individually evaluated	548	3,003
Collectively evaluated	1,484,617	1,240,699
Total loans	1,485,165	1,243,702
Loans, net	1,473,717	1,233,160
Originated | Retail & other
Financing Receivable, Allowance for Credit Losses
Beginning balance	200	132
Provision for loan losses	266	122
Charge-offs	(201)	(69)
Recoveries	16	15
Net charge-offs	(185)	(54)
Ending balance	$ 281	$ 200	132
As percent of ALLL	2.50%	1.80%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	281	200
Loans:
Individually evaluated	0	0
Collectively evaluated	23,809	18,254
Total loans	23,809	18,254
Loans, net	23,528	18,054
Originated | Commercial Portfolio Segment | Commercial & industrial
Financing Receivable, Allowance for Credit Losses
Beginning balance	4,192	3,150
Provision for loan losses	1,262	2,429
Charge-offs	(813)	(1,388)
Recoveries	42	1
Net charge-offs	(771)	(1,387)
Ending balance	$ 4,683	$ 4,192	3,150
As percent of ALLL	40.90%	39.80%
ALLL:
Individually evaluated	$ 0	$ 163
Collectively evaluated	4,683	4,029
Loans:
Individually evaluated	227	2,189
Collectively evaluated	567,873	486,411
Total loans	568,100	488,600
Loans, net	563,417	484,408
Originated | Commercial Portfolio Segment | Owner-occupied commercial real estate (“CRE”)
Financing Receivable, Allowance for Credit Losses
Beginning balance	2,115	2,263
Provision for loan losses	385	(172)
Charge-offs	(64)	0
Recoveries	3	24
Net charge-offs	(61)	24
Ending balance	$ 2,439	$ 2,115	2,263
As percent of ALLL	21.30%	20.10%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	2,439	2,115
Loans:
Individually evaluated	321	0
Collectively evaluated	283,210	237,548
Total loans	283,531	237,548
Loans, net	281,092	235,433
Originated | Commercial Portfolio Segment | Agricultural (“AG”) production
Financing Receivable, Allowance for Credit Losses
Beginning balance	112	122
Provision for loan losses	(2)	(10)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 110	$ 112	122
As percent of ALLL	1.00%	1.10%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	110	112
Loans:
Individually evaluated	0	0
Collectively evaluated	11,113	11,102
Total loans	11,113	11,102
Loans, net	11,003	10,990
Originated | Commercial Real Estate Portfolio Segment | AG real estate
Financing Receivable, Allowance for Credit Losses
Beginning balance	235	222
Provision for loan losses	20	13
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 255	$ 235	222
As percent of ALLL	2.20%	2.20%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	255	235
Loans:
Individually evaluated	0	0
Collectively evaluated	31,374	27,831
Total loans	31,374	27,831
Loans, net	31,119	27,596
Originated | Commercial Real Estate Portfolio Segment | CRE investment
Financing Receivable, Allowance for Credit Losses
Beginning balance	1,154	893
Provision for loan losses	113	261
Charge-offs	(37)	0
Recoveries	0	0
Net charge-offs	(37)	0
Ending balance	$ 1,230	$ 1,154	893
As percent of ALLL	10.70%	10.90%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	1,230	1,154
Loans:
Individually evaluated	0	549
Collectively evaluated	171,087	113,313
Total loans	171,087	113,862
Loans, net	169,857	112,708
Originated | Commercial Real Estate Portfolio Segment | Construction & land development
Financing Receivable, Allowance for Credit Losses
Beginning balance	628	656
Provision for loan losses	(197)	(28)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 431	$ 628	656
As percent of ALLL	3.80%	6.00%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	431	628
Loans:
Individually evaluated	0	0
Collectively evaluated	66,478	56,061
Total loans	66,478	56,061
Loans, net	66,047	55,433
Originated | Residential | Residential first mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	1,297	1,372
Provision for loan losses	187	(69)
Charge-offs	(85)	(8)
Recoveries	1	2
Net charge-offs	(84)	(6)
Ending balance	$ 1,400	$ 1,297	1,372
As percent of ALLL	12.20%	12.30%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	1,400	1,297
Loans:
Individually evaluated	0	253
Collectively evaluated	220,368	190,933
Total loans	220,368	191,186
Loans, net	218,968	189,889
Originated | Residential | Residential junior mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	409	373
Provision for loan losses	(31)	105
Charge-offs	0	(72)
Recoveries	30	3
Net charge-offs	30	(69)
Ending balance	$ 408	$ 409	373
As percent of ALLL	3.60%	3.90%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	408	409
Loans:
Individually evaluated	0	12
Collectively evaluated	78,379	65,631
Total loans	78,379	65,643
Loans, net	77,971	65,234
Originated | Residential | Residential construction
Financing Receivable, Allowance for Credit Losses
Beginning balance	200	266
Provision for loan losses	11	(66)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 211	$ 200	266
As percent of ALLL	1.80%	1.90%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	211	200
Loans:
Individually evaluated	0	0
Collectively evaluated	30,926	33,615
Total loans	30,926	33,615
Loans, net	30,715	33,415
Acquired
Financing Receivable, Allowance for Credit Losses
Beginning balance	2,111	2,371
Provision for loan losses	(414)	(260)
Charge-offs	(13)	(67)
Recoveries	21	67
Net charge-offs	8	0
Ending balance	$ 1,705	$ 2,111	2,371
As percent of ALLL	100.00%	100.00%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	1,705	2,111
Loans:
Individually evaluated	9,391	14,218
Collectively evaluated	671,625	830,005
Total loans	681,016	844,223
Loans, net	679,311	842,112
Acquired | Owner-occupied commercial real estate (“CRE”)
Loans:
Total loans		192,495
Acquired | Retail & other
Financing Receivable, Allowance for Credit Losses
Beginning balance	25	20
Provision for loan losses	1	5
Charge-offs	(3)	0
Recoveries	0	0
Net charge-offs	(3)	0
Ending balance	$ 23	$ 25	20
As percent of ALLL	1.40%	1.30%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	23	25
Loans:
Individually evaluated	12	12
Collectively evaluated	2,672	4,549
Total loans	2,684	4,561
Loans, net	2,661	4,536
Acquired | Commercial Portfolio Segment | Commercial & industrial
Financing Receivable, Allowance for Credit Losses
Beginning balance	742	769
Provision for loan losses	(155)	(10)
Charge-offs	0	(54)
Recoveries	1	37
Net charge-offs	1	(17)
Ending balance	$ 588	$ 742	769
As percent of ALLL	34.50%	35.10%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	588	742
Loans:
Individually evaluated	2,700	3,681
Collectively evaluated	114,120	145,056
Total loans	116,820	148,737
Loans, net	116,232	147,995
Acquired | Commercial Portfolio Segment | Owner-occupied commercial real estate (“CRE”)
Financing Receivable, Allowance for Credit Losses
Beginning balance	492	604
Provision for loan losses	(85)	(118)
Charge-offs	(10)	0
Recoveries	11	6
Net charge-offs	1	6
Ending balance	$ 408	$ 492	604
As percent of ALLL	23.90%	23.30%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	408	492
Loans:
Individually evaluated	1,185	1,689
Collectively evaluated	156,637	190,806
Total loans	157,822	192,495
Loans, net	157,414	192,003
Acquired | Commercial Portfolio Segment | Agricultural (“AG”) production
Financing Receivable, Allowance for Credit Losses
Beginning balance	17	28
Provision for loan losses	(6)	(11)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 11	$ 17	28
As percent of ALLL	0.60%	0.80%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	11	17
Loans:
Individually evaluated	0	0
Collectively evaluated	24,512	24,353
Total loans	24,512	24,353
Loans, net	24,501	24,336
Acquired | Commercial Real Estate Portfolio Segment | AG real estate
Financing Receivable, Allowance for Credit Losses
Beginning balance	61	63
Provision for loan losses	(15)	(2)
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 46	$ 61	63
As percent of ALLL	2.70%	2.90%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	46	61
Loans:
Individually evaluated	222	248
Collectively evaluated	21,848	23,699
Total loans	22,070	23,947
Loans, net	22,024	23,886
Acquired | Commercial Real Estate Portfolio Segment | CRE investment
Financing Receivable, Allowance for Credit Losses
Beginning balance	234	231
Provision for loan losses	6	2
Charge-offs	0	0
Recoveries	0	1
Net charge-offs	0	1
Ending balance	$ 240	$ 234	231
As percent of ALLL	14.10%	11.10%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	240	234
Loans:
Individually evaluated	1,686	4,741
Collectively evaluated	170,879	195,860
Total loans	172,565	200,601
Loans, net	172,325	200,367
Acquired | Commercial Real Estate Portfolio Segment | Construction & land development
Financing Receivable, Allowance for Credit Losses
Beginning balance	98	118
Provision for loan losses	(19)	(7)
Charge-offs	0	(13)
Recoveries	0	0
Net charge-offs	0	(13)
Ending balance	$ 79	$ 98	118
As percent of ALLL	4.60%	4.60%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	79	98
Loans:
Individually evaluated	603	1,053
Collectively evaluated	13,518	32,546
Total loans	14,121	33,599
Loans, net	14,042	33,501
Acquired | Residential | Residential first mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	312	412
Provision for loan losses	(70)	(123)
Charge-offs	0	0
Recoveries	4	23
Net charge-offs	4	23
Ending balance	$ 246	$ 312	412
As percent of ALLL	14.40%	14.80%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	246	312
Loans:
Individually evaluated	2,750	2,548
Collectively evaluated	134,723	169,618
Total loans	137,473	172,166
Loans, net	137,227	171,854
Acquired | Residential | Residential junior mortgage
Financing Receivable, Allowance for Credit Losses
Beginning balance	79	88
Provision for loan losses	(20)	(9)
Charge-offs	0	0
Recoveries	5	0
Net charge-offs	5	0
Ending balance	$ 64	$ 79	88
As percent of ALLL	3.80%	3.70%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	64	79
Loans:
Individually evaluated	233	166
Collectively evaluated	32,716	40,218
Total loans	32,949	40,384
Loans, net	32,885	40,305
Acquired | Residential | Residential construction
Financing Receivable, Allowance for Credit Losses
Beginning balance	51	38
Provision for loan losses	(51)	13
Charge-offs	0	0
Recoveries	0	0
Net charge-offs	0	0
Ending balance	$ 0	$ 51	$ 38
As percent of ALLL	0.00%	2.40%
ALLL:
Individually evaluated	$ 0	$ 0
Collectively evaluated	0	51
Loans:
Individually evaluated	0	80
Collectively evaluated	0	3,300
Total loans	0	3,380
Loans, net	$ 0	$ 3,329