LOANS AND ALLOWANCE FOR CREDIT LOSSES - Outstanding loan balances by loan class prior to allocation of net deferred fees and costs (Details) - USD ($)	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	$ 931,620,000	$ 946,661,000
Net Deferred Fees and Costs	543,000	624,000
Subtotal: Total Loans Held for Investment	932,163,000	947,285,000
Loans held for sale	452,000	1,140,000
Allowance for credit losses	(9,038,000)	(9,412,000)	$ (8,068,000)	$ (7,672,000)
Net loans	923,577,000	939,013,000
Real Estate
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	839,239,000	853,668,000
Loans held for sale	452,000	1,140,000
Allowance for credit losses	(8,462,000)	(8,836,000)	(7,572,000)	(7,215,000)
Agricultural
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	1,230,000	984,000
Allowance for credit losses	(5,000)	(2,000)	(2,000)	(2,000)
Commercial and Industrial
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	66,187,000	66,924,000
Allowance for credit losses	(441,000)	(452,000)	(341,000)	(313,000)
Consumer
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	4,881,000	4,953,000
Allowance for credit losses	(82,000)	(74,000)	(94,000)	(98,000)
State and Political Subdivisions
LOANS AND ALLOWANCE FOR CREDIT LOSSES
Subtotal: Total Loans	20,083,000	20,132,000
Allowance for credit losses	$ (48,000)	$ (48,000)	$ (59,000)	$ (44,000)