LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Allowance for credit losses [Roll Forward]
Beginning balance	$ 12,822	$ 11,133	$ 11,133
Provision for (reversal of) loan losses	0	525	2,100
Charge-offs	(157)	(6)	(685)
Recoveries	81	63	274
Net (charge-offs) recoveries	(76)	57	(411)
Ending balance	12,746	11,715	12,822
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	375	467	855
Loans collectively evaluated for impairment	12,371	11,248	11,967
Ending balance	12,746	11,715	12,822
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	10,055	8,496	10,874
Loans collectively evaluated for impairment	733,552	722,739	764,620
Ending balance	743,607	731,235	775,494
Commercial [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	3,198	2,625	2,625
Provision for (reversal of) loan losses	(568)	(85)	1,036
Charge-offs	(150)	0	(509)
Recoveries	19	9	46
Net (charge-offs) recoveries	(131)	9	(463)
Ending balance	2,499	2,549	3,198
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	37	47	496
Loans collectively evaluated for impairment	2,462	2,502	2,702
Ending balance	2,499	2,549	3,198
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	2,174	3,191	2,902
Loans collectively evaluated for impairment	111,401	127,558	122,275
Ending balance	113,575	130,749	125,177
Commercial Real Estate [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	5,890	5,460	5,460
Provision for (reversal of) loan losses	496	(46)	572
Charge-offs	0	0	(142)
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	(142)
Ending balance	6,386	5,414	5,890
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	21	36	21
Loans collectively evaluated for impairment	6,365	5,378	5,869
Ending balance	6,386	5,414	5,890
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	625	1,946	642
Loans collectively evaluated for impairment	418,915	391,964	419,464
Ending balance	419,540	393,910	420,106
Agriculture [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	1,632	1,547	1,547
Provision for (reversal of) loan losses	202	(124)	85
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	1,834	1,423	1,632
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	1,834	1,423	1,632
Ending balance	1,834	1,423	1,632
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	4,779	0	4,830
Loans collectively evaluated for impairment	104,970	104,104	118,796
Ending balance	109,749	104,104	123,626
Residential Mortgage [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	643	628	628
Provision for (reversal of) loan losses	(197)	(1)	(19)
Charge-offs	0	0	0
Recoveries	56	16	34
Net (charge-offs) recoveries	56	16	34
Ending balance	502	643	643
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	267	309	287
Loans collectively evaluated for impairment	235	334	356
Ending balance	502	643	643
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,351	2,192	1,551
Loans collectively evaluated for impairment	50,331	42,596	49,513
Ending balance	51,682	44,788	51,064
Residential Construction [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	318	360	360
Provision for (reversal of) loan losses	(102)	(13)	(173)
Charge-offs	0	0	0
Recoveries	1	1	131
Net (charge-offs) recoveries	1	1	131
Ending balance	217	348	318
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	48	71	49
Loans collectively evaluated for impairment	169	277	269
Ending balance	217	348	318
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	743	644	560
Loans collectively evaluated for impairment	16,883	20,110	19,564
Ending balance	17,626	20,754	20,124
Consumer [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	279	342	342
Provision for (reversal of) loan losses	0	(68)	(92)
Charge-offs	(7)	(6)	(34)
Recoveries	5	37	63
Net (charge-offs) recoveries	(2)	31	29
Ending balance	277	305	279
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	2	4	2
Loans collectively evaluated for impairment	275	301	277
Ending balance	277	305	279
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	383	523	389
Loans collectively evaluated for impairment	31,052	36,407	35,008
Ending balance	31,435	36,930	35,397
Unallocated [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	862	171	171
Provision for (reversal of) loan losses	169	862	691
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	1,031	1,033	862
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	1,031	1,033	862
Ending balance	$ 1,031	$ 1,033	$ 862

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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