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Loans - Loans and Allowance for Credit Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Jun. 29, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Loans [Abstract]
Collectively evaluated for impairment	$ 20,938			$ 19,796
Individually evaluated for impairment	1,516			1,903
Total Allowance for Credit Losses - Loans for impairment	22,454	$ 22,109	$ 22,109	21,699	$ 21,695	$ 22,797	$ 21,153
Collectively evaluated for impairment	2,302,228			2,287,674
Individually evaluated for impairment	33,160			25,568
Total Loans	2,335,388			2,313,242
Consumer [Member]
Loans [Abstract]
Collectively evaluated for impairment	402			324
Individually evaluated for impairment	923			1,014
Total Allowance for Credit Losses - Loans for impairment	1,325	1,119		1,338	1,163	1,008	1,412
Collectively evaluated for impairment	108,463			108,478
Individually evaluated for impairment	995			1,027
Total Loans	109,458			109,505
Other Commercial Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	2,007			3,019
Individually evaluated for impairment	424			747
Total Allowance for Credit Losses - Loans for impairment	2,431	1,993		3,766	2,028	3,459	2,313
Collectively evaluated for impairment	169,246			152,430
Individually evaluated for impairment	2,099			2,582
Total Loans	171,345			155,012
Other Agricultural Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	125			133
Individually evaluated for impairment	0			0
Total Allowance for Credit Losses - Loans for impairment	125	132		133	116	206	270
Collectively evaluated for impairment	26,739			29,125
Individually evaluated for impairment	403			537
Total Loans	27,142			29,662
State and Political Subdivision Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	58			61
Individually evaluated for impairment	0			0
Total Allowance for Credit Losses - Loans for impairment	58	56		61	63	63	45
Collectively evaluated for impairment	51,644			54,182
Individually evaluated for impairment	0			0
Total Loans	51,644			54,182
Unallocated [Member]
Loans [Abstract]
Collectively evaluated for impairment	81			356
Individually evaluated for impairment	0			0
Total Allowance for Credit Losses - Loans for impairment	81	34		356	1,766	26	367
Collectively evaluated for impairment	0			0
Individually evaluated for impairment	0			0
Total Loans	0			0
Residential [Member]
Loans [Abstract]
Total Loans	293,365			301,735
Residential [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	3,142			1,902
Individually evaluated for impairment	68			38
Total Allowance for Credit Losses - Loans for impairment	3,210	3,062		1,940	1,986	2,355	2,354
Collectively evaluated for impairment	342,246			349,909
Individually evaluated for impairment	2,544			1,489
Total Loans	344,790			351,398
Commercial [Member]
Loans [Abstract]
Total Loans	1,180,655			1,121,435
Commercial [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	9,444			9,070
Individually evaluated for impairment	9			104
Total Allowance for Credit Losses - Loans for impairment	9,453	9,898		9,174	9,287	10,283	9,178
Collectively evaluated for impairment	1,157,239			1,105,847
Individually evaluated for impairment	23,416			15,588
Total Loans	1,180,655			1,121,435
Agricultural [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	4,804			3,529
Individually evaluated for impairment	0			0
Total Allowance for Credit Losses - Loans for impairment	4,804	4,542		3,529	3,815	3,770	3,264
Collectively evaluated for impairment	340,336			323,660
Individually evaluated for impairment	2,151			4,062
Total Loans	342,487			327,722
Construction [Member]
Loans [Abstract]
Total Loans	107,867			164,326
Construction [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	875			1,402
Individually evaluated for impairment	92			0
Total Allowance for Credit Losses - Loans for impairment	967	$ 1,273		1,402	$ 1,471	$ 1,627	$ 1,950
Collectively evaluated for impairment	106,315			164,043
Individually evaluated for impairment	1,552			283
Total Loans	$ 107,867			$ 164,326