LOANS AND ALLOWANCE FOR CREDIT LOSSES - Past due (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Current - 29 Days Past Due	$ 920,109,000	$ 902,853,000
Total	934,599,000	911,078,000	$ 881,038,000
90 Days or Greater Past Due and Still Accruing Interest	1,831,000	1,065,000
Financial Asset, 30 to 59 Days Past Due
Total	3,226,000	2,182,000
Financing Receivables, 60 to 89 Days Past Due
Total	5,897,000	383,000
Financing Receivables, Equal to Greater than 90 Days Past Due
Total	5,367,000	5,660,000
Financial Asset, Past Due
Total	14,490,000	8,225,000
Real Estate
Current - 29 Days Past Due	822,285,000	803,890,000
Total	836,213,000	811,493,000	784,126,000
90 Days or Greater Past Due and Still Accruing Interest	1,831,000	1,065,000
Real Estate | Financial Asset, 30 to 59 Days Past Due
Total	3,043,000	2,155,000
Real Estate | Financing Receivables, 60 to 89 Days Past Due
Total	5,625,000	379,000
Real Estate | Financing Receivables, Equal to Greater than 90 Days Past Due
Total	5,260,000	5,069,000
Real Estate | Financial Asset, Past Due
Total	13,928,000	7,603,000
Agricultural
Current - 29 Days Past Due	1,008,000	671,000
Total	1,008,000	671,000	708,000
Commercial and Industrial
Current - 29 Days Past Due	66,276,000	66,312,000
Total	66,804,000	66,909,000	62,866,000
Commercial and Industrial | Financial Asset, 30 to 59 Days Past Due
Total	149,000	6,000
Commercial and Industrial | Financing Receivables, 60 to 89 Days Past Due
Total	272,000
Commercial and Industrial | Financing Receivables, Equal to Greater than 90 Days Past Due
Total	107,000	591,000
Commercial and Industrial | Financial Asset, Past Due
Total	528,000	597,000
Consumer
Current - 29 Days Past Due	6,132,000	5,799,000
Total	6,166,000	5,824,000	6,218,000
Consumer | Financial Asset, 30 to 59 Days Past Due
Total	34,000	21,000
Consumer | Financing Receivables, 60 to 89 Days Past Due
Total		4,000
Consumer | Financial Asset, Past Due
Total	34,000	25,000
State and Political Subdivisions
Current - 29 Days Past Due	24,408,000	26,181,000
Total	$ 24,408,000	$ 26,181,000	$ 27,120,000