LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES - Loan Portfolio and Allowance for Credit Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	$ 2,350,622	$ 2,313,242
Allowance for credit losses – loans	22,806	21,699	$ 21,153	$ 18,552
Net loans	2,327,816	2,291,543
Consumer [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	88,210	109,505
Allowance for credit losses – loans	1,201	1,338	1,412	135
Other Commercial Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	179,166	155,012
Allowance for credit losses – loans	2,534	3,766	2,313	1,040
Other Agricultural Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	30,247	29,662
Allowance for credit losses – loans	115	133	270	489
State and Political Subdivision Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	52,100	54,182
Allowance for credit losses – loans	55	61	45	322
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]
Total loans	340,972	351,398
Allowance for credit losses – loans	3,112	1,940	2,354	1,056
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]
Total loans	1,218,514	1,121,435
Allowance for credit losses – loans	10,017	9,174	9,178	10,120
Agricultural [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Total loans	347,448	327,722
Allowance for credit losses – loans	4,841	3,529	3,264	4,589
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]
Total loans	93,965	164,326
Allowance for credit losses – loans	$ 916	$ 1,402	$ 1,950	$ 801