LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES - Loan Receivables on Nonaccrual Status (Details) - USD ($)	Dec. 31, 2025	Dec. 31, 2024
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	$ 10,298,000	$ 5,648,000
Nonaccrual Without a related allowance	16,304,000	20,053,000
90 days or greater past due and accruing	229,000	276,000
Total non-performing loans	26,831,000	25,977,000
Consumer [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	770,000	1,002,000
Nonaccrual Without a related allowance	0	0
90 days or greater past due and accruing	15,000	7,000
Total non-performing loans	785,000	1,009,000
Other Commercial Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	6,282,000	2,382,000
Nonaccrual Without a related allowance	1,546,000	200,000
90 days or greater past due and accruing	8,000	0
Total non-performing loans	7,836,000	2,582,000
Other Agricultural Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	403,000	537,000
90 days or greater past due and accruing	0	0
Total non-performing loans	403,000	537,000
Mortgages [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	153,000	165,000
Nonaccrual Without a related allowance	3,229,000	2,541,000
90 days or greater past due and accruing	0	0
Total non-performing loans	3,382,000	2,706,000
Home Equity [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	61,000	165,000
90 days or greater past due and accruing	151,000	0
Total non-performing loans	212,000	165,000
Commercial [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	2,860,000	2,099,000
Nonaccrual Without a related allowance	8,637,000	12,265,000
90 days or greater past due and accruing	0	0
Total non-performing loans	11,497,000	14,364,000
Agricultural [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	0	0
Nonaccrual Without a related allowance	2,145,000	4,062,000
90 days or greater past due and accruing	55,000	269,000
Total non-performing loans	2,200,000	4,331,000
Construction [Member] | Real Estate Loans [Member]
LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES [Abstract]
Nonaccrual With a related allowance	233,000	0
Nonaccrual Without a related allowance	283,000	283,000
90 days or greater past due and accruing	0	0
Total non-performing loans	$ 516,000	$ 283,000