LOANS AND ALLOWANCE FOR LOAN LOSSES - Schedule of Allowance for Loan Losses Activity (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Allowance for loan losses:
Beginning balance	$ 14,651	$ 12,859	$ 12,859
Provision for loan losses	575	600	2,250
Loans charged-off	(78)	(116)	(918)
Recoveries	42	32	460
Ending balance	15,190	13,375	14,651
Allowance ending balance:
Individually evaluated for impairment	877	175	493
Collectively evaluated for impairment	14,313	13,200	14,158
Ending balance	15,190	13,375	14,651
Loans:
Individually evaluated for impairment	9,008	7,629	11,356
Collectively evaluated for impairment	1,646,695	1,393,705	1,648,179
Ending balance	1,655,703	1,401,334	1,659,535
Commercial and industrial
Allowance for loan losses:
Beginning balance	1,751	1,581	1,581
Provision for loan losses	213	164	426
Loans charged-off	(6)	(10)	(367)
Recoveries	5	2	111
Ending balance	1,963	1,737	1,751
Allowance ending balance:
Individually evaluated for impairment	57	12	64
Collectively evaluated for impairment	1,906	1,725	1,687
Ending balance	1,963	1,737	1,751
Loans:
Individually evaluated for impairment	483	816	1,022
Collectively evaluated for impairment	245,693	205,492	260,757
Ending balance	246,176	206,308	261,779
Construction and development
Allowance for loan losses:
Beginning balance	1,920	1,724	1,724
Provision for loan losses	81	(24)	196
Ending balance	2,001	1,700	1,920
Allowance ending balance:
Individually evaluated for impairment			4
Collectively evaluated for impairment	2,001	1,700	1,916
Ending balance	2,001	1,700	1,920
Loans:
Individually evaluated for impairment	1,250		1,250
Collectively evaluated for impairment	249,602	193,909	236,253
Ending balance	250,852	193,909	237,503
Commercial real estate
Allowance for loan losses:
Beginning balance	6,025	4,585	4,585
Provision for loan losses	269	439	1,472
Loans charged-off		(33)	(33)
Recoveries			1
Ending balance	6,294	4,991	6,025
Allowance ending balance:
Individually evaluated for impairment	746	69	341
Collectively evaluated for impairment	5,548	4,922	5,684
Ending balance	6,294	4,991	6,025
Loans:
Individually evaluated for impairment	5,453	4,918	7,153
Collectively evaluated for impairment	576,473	445,158	575,366
Ending balance	581,926	450,076	582,519
Farmland
Allowance for loan losses:
Beginning balance	643	523	523
Provision for loan losses	16	83	120
Ending balance	659	606	643
Allowance ending balance:
Individually evaluated for impairment	74	80	78
Collectively evaluated for impairment	585	526	565
Ending balance	659	606	643
Loans:
Individually evaluated for impairment	139	230	140
Collectively evaluated for impairment	72,135	63,741	67,705
Ending balance	72,274	63,971	67,845
1-4 family residential
Allowance for loan losses:
Beginning balance	2,868	3,022	3,022
Provision for loan losses	7	(147)	(196)
Loans charged-off	(6)	(13)	(93)
Recoveries	1	5	135
Ending balance	2,870	2,867	2,868
Allowance ending balance:
Individually evaluated for impairment		3	6
Collectively evaluated for impairment	2,870	2,864	2,862
Ending balance	2,870	2,867	2,868
Loans:
Individually evaluated for impairment	1,450	800	1,383
Collectively evaluated for impairment	389,168	376,478	391,684
Ending balance	390,618	377,278	393,067
Multi-family residential
Allowance for loan losses:
Beginning balance	631	629	629
Provision for loan losses	(56)	18	2
Ending balance	575	647	631
Allowance ending balance:
Collectively evaluated for impairment	575	647	631
Ending balance	575	647	631
Loans:
Individually evaluated for impairment		212
Collectively evaluated for impairment	37,430	37,780	38,386
Ending balance	37,430	37,992	38,386
Consumer
Allowance for loan losses:
Beginning balance	565	602	602
Provision for loan losses	46		127
Loans charged-off	(17)	(28)	(254)
Recoveries	23	11	90
Ending balance	617	585	565
Allowance ending balance:
Collectively evaluated for impairment	617	585	565
Ending balance	617	585	565
Loans:
Collectively evaluated for impairment	56,158	48,982	54,777
Ending balance	56,158	48,982	54,777
Agricultural
Allowance for loan losses:
Beginning balance	238	187	187
Provision for loan losses	(35)	46	(12)
Loans charged-off			(2)
Recoveries			65
Ending balance	203	233	238
Allowance ending balance:
Individually evaluated for impairment		11
Collectively evaluated for impairment	203	222	238
Ending balance	203	233	238
Loans:
Individually evaluated for impairment	233	653	408
Collectively evaluated for impairment	19,761	21,892	22,869
Ending balance	19,994	22,545	23,277
Overdrafts
Allowance for loan losses:
Beginning balance	10	6	6
Provision for loan losses	34	21	115
Loans charged-off	(49)	(32)	(169)
Recoveries	13	14	58
Ending balance	8	9	10
Allowance ending balance:
Collectively evaluated for impairment	8	9	10
Ending balance	8	9	10
Loans:
Collectively evaluated for impairment	275	273	382
Ending balance	$ 275	$ 273	$ 382

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

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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 of valuation allowance for financing receivables that are expected to be uncollectible that were individually 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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