LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES - Loans and Allowance for Credit Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	$ 20,893	$ 19,796
Individually evaluated for impairment	1,913	1,903
Total Allowance for Credit Losses - Loans	22,806	21,699	$ 21,153	$ 18,552
Collectively evaluated for impairment	2,311,682	2,287,674
Individually evaluated for impairment	38,940	25,568
Total Loans	2,350,622	2,313,242
Consumer [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	327	324
Individually evaluated for impairment	874	1,014
Total Allowance for Credit Losses - Loans	1,201	1,338	1,412	135
Collectively evaluated for impairment	87,301	108,478
Individually evaluated for impairment	909	1,027
Total Loans	88,210	109,505
Other Commercial Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	1,903	3,019
Individually evaluated for impairment	631	747
Total Allowance for Credit Losses - Loans	2,534	3,766	2,313	1,040
Collectively evaluated for impairment	171,343	152,430
Individually evaluated for impairment	7,823	2,582
Total Loans	179,166	155,012
Other Agricultural Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	115	133
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans	115	133	270	489
Collectively evaluated for impairment	29,844	29,125
Individually evaluated for impairment	403	537
Total Loans	30,247	29,662
State and Political Subdivision Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	55	61
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans	55	61	45	322
Collectively evaluated for impairment	52,100	54,182
Individually evaluated for impairment	0	0
Total Loans	52,100	54,182
Unallocated [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	15	356
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans	15	356	367	0
Collectively evaluated for impairment	0	0
Individually evaluated for impairment	0	0
Total Loans	0	0
Residential [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total Loans	288,664	301,735
Residential [Member] \| Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	3,050	1,902
Individually evaluated for impairment	62	38
Total Allowance for Credit Losses - Loans	3,112	1,940	2,354	1,056
Collectively evaluated for impairment	338,600	349,909
Individually evaluated for impairment	2,372	1,489
Total Loans	340,972	351,398
Commercial [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total Loans	1,218,514	1,121,435
Commercial [Member] \| Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	9,757	9,070
Individually evaluated for impairment	260	104
Total Allowance for Credit Losses - Loans	10,017	9,174	9,178	10,120
Collectively evaluated for impairment	1,193,742	1,105,847
Individually evaluated for impairment	24,772	15,588
Total Loans	1,218,514	1,121,435
Agricultural [Member] \| Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	4,841	3,529
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans	4,841	3,529	3,264	4,589
Collectively evaluated for impairment	345,302	323,660
Individually evaluated for impairment	2,146	4,062
Total Loans	347,448	327,722
Construction [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total Loans	93,965	164,326
Construction [Member] \| Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Collectively evaluated for impairment	830	1,402
Individually evaluated for impairment	86	0
Total Allowance for Credit Losses - Loans	916	1,402	$ 1,950	$ 801
Collectively evaluated for impairment	93,450	164,043
Individually evaluated for impairment	515	283
Total Loans	$ 93,965	$ 164,326

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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