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Loans - Loans and Allowance for Credit Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Jun. 30, 2026	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024
Loans [Abstract]
Collectively evaluated for impairment	$ 21,637		$ 20,893
Individually evaluated for impairment	2,149		1,913
Total Allowance for Credit Losses - Loans for impairment	23,786	$ 23,559	22,806	$ 22,454	$ 22,109	$ 21,699
Collectively evaluated for impairment	2,335,069		2,232,331
Individually evaluated for impairment	52,627		38,940
Total Loans	2,387,696		2,271,271
Consumer [Member]
Loans [Abstract]
Collectively evaluated for impairment	77		327
Individually evaluated for impairment	521		874
Total Allowance for Credit Losses - Loans for impairment	598	1,191	1,201	1,325	1,119	1,338
Collectively evaluated for impairment	8,060		7,950
Individually evaluated for impairment	537		909
Total Loans	8,597		8,859
Other Commercial Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	2,099		1,903
Individually evaluated for impairment	546		631
Total Allowance for Credit Losses - Loans for impairment	2,645	3,037	2,534	2,431	1,993	3,766
Collectively evaluated for impairment	172,351		171,343
Individually evaluated for impairment	6,626		7,823
Total Loans	178,977		179,166
Other Agricultural Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	187		115
Individually evaluated for impairment	31		0
Total Allowance for Credit Losses - Loans for impairment	218	190	115	125	132	133
Collectively evaluated for impairment	30,821		29,844
Individually evaluated for impairment	502		403
Total Loans	31,323		30,247
State and Political Subdivision Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	121		55
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	121	106	55	58	56	61
Collectively evaluated for impairment	82,556		52,100
Individually evaluated for impairment	0		0
Total Loans	82,556		52,100
Unallocated [Member]
Loans [Abstract]
Collectively evaluated for impairment	189		15
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	189	34	15	81	34	356
Collectively evaluated for impairment	0		0
Individually evaluated for impairment	0		0
Total Loans	0		0
Residential [Member]
Loans [Abstract]
Total Loans	283,082		288,664
Residential [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	2,590		3,050
Individually evaluated for impairment	17		62
Total Allowance for Credit Losses - Loans for impairment	2,607	2,671	3,112	3,210	3,062	1,940
Collectively evaluated for impairment	333,420		338,600
Individually evaluated for impairment	2,770		2,372
Total Loans	336,190		340,972
Commercial [Member]
Loans [Abstract]
Total Loans	1,276,050		1,218,514
Commercial [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	10,737		9,757
Individually evaluated for impairment	965		260
Total Allowance for Credit Losses - Loans for impairment	11,702	11,006	10,017	9,453	9,898	9,174
Collectively evaluated for impairment	1,237,119		1,193,742
Individually evaluated for impairment	38,931		24,772
Total Loans	1,276,050		1,218,514
Agricultural [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	4,685		4,841
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	4,685	4,411	4,841	4,804	4,542	3,529
Collectively evaluated for impairment	368,195		345,302
Individually evaluated for impairment	2,310		2,146
Total Loans	370,505		347,448
Construction [Member]
Loans [Abstract]
Total Loans	103,498		93,965
Construction [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	952		830
Individually evaluated for impairment	69		86
Total Allowance for Credit Losses - Loans for impairment	1,021	$ 913	916	$ 967	$ 1,273	$ 1,402
Collectively evaluated for impairment	102,547		93,450
Individually evaluated for impairment	951		515
Total Loans	$ 103,498		$ 93,965