LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Allowance for credit losses [Roll Forward]
Beginning balance	$ 13,631	$ 12,838	$ 12,356	$ 12,822	$ 12,822
Provision for loan losses	800	0	2,250	0	0
Charge-offs	0	(558)	(197)	(723)	(779)
Recoveries	25	7	47	188	313
Net (charge-offs) recoveries	25	(551)	(150)	(535)	(466)
Ending balance	14,456	12,287	14,456	12,287	12,356
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	251	279	251	279	273
Loans collectively evaluated for impairment	14,205	12,008	14,205	12,008	12,083
Ending balance	14,456	12,287	14,456	12,287	12,356
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	18,106	4,758	18,106	4,758	4,475
Loans collectively evaluated for impairment	965,867	761,795	965,867	761,795	776,170
Ending balance	983,973	766,553	983,973	766,553	780,645
Commercial [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	2,338	2,372	2,354	3,198	3,198
Provision for loan losses	(5)	384	151	(375)	(415)
Charge-offs	0	(446)	(184)	(596)	(638)
Recoveries	1	2	13	85	209
Net (charge-offs) recoveries	1	(444)	(171)	(511)	(429)
Ending balance	2,334	2,312	2,334	2,312	2,354
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	16	30	16	30	26
Loans collectively evaluated for impairment	2,318	2,282	2,318	2,282	2,328
Ending balance	2,334	2,312	2,334	2,312	2,354
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,109	1,849	1,109	1,849	1,651
Loans collectively evaluated for impairment	330,336	103,064	330,336	103,064	104,489
Ending balance	331,445	104,913	331,445	104,913	106,140
Commercial Real Estate [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	7,434	6,429	6,846	5,890	5,890
Provision for loan losses	1,075	154	1,663	693	956
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Net (charge-offs) recoveries	0	0	0	0	0
Ending balance	8,509	6,583	8,509	6,583	6,846
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	20	0	20	19
Loans collectively evaluated for impairment	8,509	6,563	8,509	6,563	6,827
Ending balance	8,509	6,583	8,509	6,583	6,846
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	5,390	596	5,390	596	716
Loans collectively evaluated for impairment	450,847	433,102	450,847	433,102	451,058
Ending balance	456,237	433,698	456,237	433,698	451,774
Agriculture [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	1,655	1,913	2,054	1,632	1,632
Provision for loan losses	225	280	(174)	561	520
Charge-offs	0	(98)	0	(98)	(98)
Recoveries	0	0	0	0	0
Net (charge-offs) recoveries	0	(98)	0	(98)	(98)
Ending balance	1,880	2,095	1,880	2,095	2,054
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0	0	0
Loans collectively evaluated for impairment	1,880	2,095	1,880	2,095	2,054
Ending balance	1,880	2,095	1,880	2,095	2,054
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	9,130	0	9,130	0	0
Loans collectively evaluated for impairment	92,915	118,516	92,915	118,516	115,751
Ending balance	102,045	118,516	102,045	118,516	115,751
Residential Mortgage [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	540	436	466	643	643
Provision for loan losses	133	17	207	(262)	(251)
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	72	74
Net (charge-offs) recoveries	0	0	0	72	74
Ending balance	673	453	673	453	466
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	162	175	162	175	171
Loans collectively evaluated for impairment	511	278	511	278	295
Ending balance	673	453	673	453	466
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,047	1,093	1,047	1,093	1,084
Loans collectively evaluated for impairment	66,193	59,747	66,193	59,747	63,859
Ending balance	67,240	60,840	67,240	60,840	64,943
Residential Construction [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	245	196	201	318	318
Provision for loan losses	(99)	52	(55)	(91)	(138)
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	21	21
Net (charge-offs) recoveries	0	0	0	21	21
Ending balance	146	248	146	248	201
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	72	53	72	53	56
Loans collectively evaluated for impairment	74	195	74	195	145
Ending balance	146	248	146	248	201
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	661	700	661	700	691
Loans collectively evaluated for impairment	5,949	19,514	5,949	19,514	14,521
Ending balance	6,610	20,214	6,610	20,214	15,212
Consumer [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	224	263	236	279	279
Provision for loan losses	(24)	(6)	(33)	(12)	(9)
Charge-offs	0	(14)	(13)	(29)	(43)
Recoveries	24	5	34	10	9
Net (charge-offs) recoveries	24	(9)	21	(19)	(34)
Ending balance	224	248	224	248	236
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	1	1	1	1	1
Loans collectively evaluated for impairment	223	247	223	247	235
Ending balance	224	248	224	248	236
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	769	520	769	520	333
Loans collectively evaluated for impairment	19,627	27,852	19,627	27,852	26,492
Ending balance	20,396	28,372	20,396	28,372	26,825
Unallocated [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	1,195	1,229	199	862	862
Provision for loan losses	(505)	(881)	491	(514)	(663)
Charge-offs	0	0	0	0	0
Recoveries	0	0	0	0	0
Net (charge-offs) recoveries	0	0	0	0	0
Ending balance	690	348	690	348	199
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0	0	0
Loans collectively evaluated for impairment	690	348	690	348	199
Ending balance	$ 690	$ 348	$ 690	$ 348	$ 199

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

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- Definition

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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