LOANS AND RELATED ALLOWANCE FOR LOAN LOSSES, Impaired Financing Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	$ 14,653	$ 17,905
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	11,292	14,878
Recorded Investment With Allowance	677	655
Total Recorded Investment	11,969	15,533
Related Allowance	102	121
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	13,040	15,880	$ 18,278
Interest Income Recognized	356	395	468
Interest Income Recognized Cash Basis	10	31	27
Real Estate Loans [Member] \| Mortgages [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	395	697
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	242	495
Recorded Investment With Allowance	39	45
Total Recorded Investment	281	540
Related Allowance	4	6
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	421	682	956
Interest Income Recognized	12	16	20
Interest Income Recognized Cash Basis	0	0	0
Real Estate Loans [Member] \| Home Equity [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	71	97
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	39	37
Recorded Investment With Allowance	15	43
Total Recorded Investment	54	80
Related Allowance	0	6
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	64	99	139
Interest Income Recognized	4	4	6
Interest Income Recognized Cash Basis	0	0	0
Real Estate Loans [Member] \| Commercial [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	6,655	9,330
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	5,314	8,096
Recorded Investment With Allowance	361	285
Total Recorded Investment	5,675	8,381
Related Allowance	57	61
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	6,216	8,789	10,354
Interest Income Recognized	207	288	358
Interest Income Recognized Cash Basis	10	31	27
Real Estate Loans [Member] \| Agricultural [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	6,062	5,694
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	5,192	5,167
Recorded Investment With Allowance	188	188
Total Recorded Investment	5,380	5,355
Related Allowance	24	14
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	5,540	4,562	3,918
Interest Income Recognized	126	82	75
Interest Income Recognized Cash Basis	0	0	0
Consumer [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	4
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	0
Recorded Investment With Allowance	4
Total Recorded Investment	4
Related Allowance	4
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	1		3
Interest Income Recognized	0		0
Interest Income Recognized Cash Basis	0		0
Other Commercial Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	797	813
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	32	92
Recorded Investment With Allowance	70	94
Total Recorded Investment	102	186
Related Allowance	13	34
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	260	704	1,671
Interest Income Recognized	3	2	3
Interest Income Recognized Cash Basis	0	0	0
Other Agricultural Loans [Member]
Impaired Financing Receivable [Abstract]
Unpaid Principal Balance	669	1,274
Impaired Financing Receivable, Recorded Investment [Abstract]
Recorded Investment With No Allowance	473	991
Recorded Investment With Allowance	0	0
Total Recorded Investment	473	991
Related Allowance	0	0
Impaired Financing Receivable, Average Recorded Investment [Abstract]
Average Recorded Investment	538	1,044	1,237
Interest Income Recognized	4	3	6
Interest Income Recognized Cash Basis	$ 0	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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