LOANS, Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Allowance for credit losses [Roll Forward]
Beginning balance	$ 15,416	$ 12,356	$ 12,356
Provision for (reversal of) loan losses	300	650	3,050
Charge-offs	(16)	(154)	(227)
Recoveries	13	17	237
Net (charge-offs) recoveries	(3)	(137)	10
Ending balance	15,713	12,869	15,416
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	4,124	259	2,347
Loans collectively evaluated for impairment	11,589	12,610	13,069
Ending balance	15,713	12,869	15,416
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	18,247	4,304	17,471
Loans collectively evaluated for impairment	944,195	766,261	875,743
Ending balance	962,442	770,565	893,214
Commercial [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	2,252	2,354	2,354
Provision for (reversal of) loan losses	(779)	386	(91)
Charge-offs	(13)	(145)	(212)
Recoveries	8	11	201
Net (charge-offs) recoveries	(5)	(134)	(11)
Ending balance	1,468	2,606	2,252
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	21	11
Loans collectively evaluated for impairment	1,468	2,585	2,241
Ending balance	1,468	2,606	2,252
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	284	1,462	1,024
Loans collectively evaluated for impairment	292,864	111,884	254,902
Ending balance	293,148	113,346	255,926
Commercial Real Estate [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	7,915	6,846	6,846
Provision for (reversal of) loan losses	(354)	560	1,069
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	7,561	7,406	7,915
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	19	0
Loans collectively evaluated for impairment	7,561	7,387	7,915
Ending balance	7,561	7,406	7,915
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	6,803	756	4,875
Loans collectively evaluated for impairment	490,045	451,855	449,178
Ending balance	496,848	452,611	454,053
Agriculture [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	3,834	2,054	2,054
Provision for (reversal of) loan losses	1,337	(266)	1,780
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	5,171	1,788	3,834
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	3,964	0	2,093
Loans collectively evaluated for impairment	1,207	1,788	1,741
Ending balance	5,171	1,788	3,834
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	9,130	0	9,130
Loans collectively evaluated for impairment	70,825	94,303	85,918
Ending balance	79,955	94,303	95,048
Residential Mortgage [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	635	466	466
Provision for (reversal of) loan losses	45	70	169
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	680	536	635
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	155	168	159
Loans collectively evaluated for impairment	525	368	476
Ending balance	680	536	635
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	1,024	1,075	1,036
Loans collectively evaluated for impairment	70,088	65,109	63,461
Ending balance	71,112	66,184	64,497
Residential Construction [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	128	201	201
Provision for (reversal of) loan losses	(91)	59	(73)
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	37	260	128
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	4	49	83
Loans collectively evaluated for impairment	33	211	45
Ending balance	37	260	128
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	255	681	652
Loans collectively evaluated for impairment	2,407	18,405	3,571
Ending balance	2,662	19,086	4,223
Consumer [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	214	236	236
Provision for (reversal of) loan losses	(30)	18	(43)
Charge-offs	(3)	(9)	(15)
Recoveries	5	6	36
Net (charge-offs) recoveries	2	(3)	21
Ending balance	186	251	214
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	1	2	1
Loans collectively evaluated for impairment	185	249	213
Ending balance	186	251	214
Loans individually and collectively evaluated for impairment [Abstract]
Loans individually evaluated for impairment	751	330	754
Loans collectively evaluated for impairment	17,966	24,705	18,713
Ending balance	18,717	25,035	19,467
Unallocated [Member]
Allowance for credit losses [Roll Forward]
Beginning balance	438	199	199
Provision for (reversal of) loan losses	172	(177)	239
Charge-offs	0	0	0
Recoveries	0	0	0
Net (charge-offs) recoveries	0	0	0
Ending balance	610	22	438
Period-end amount allocated to [Abstract]
Loans individually evaluated for impairment	0	0	0
Loans collectively evaluated for impairment	610	22	438
Ending balance	$ 610	$ 22	$ 438

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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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