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Loans - Loans and Allowance for Credit Losses by Portfolio Segment (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Mar. 31, 2026	Dec. 31, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Loans [Abstract]
Collectively evaluated for impairment	$ 21,127		$ 20,893
Individually evaluated for impairment	2,432		1,913
Total Allowance for Credit Losses - Loans for impairment	23,559	$ 22,894	22,806	$ 22,109	$ 22,081	$ 21,699
Collectively evaluated for impairment	2,353,219		2,311,682
Individually evaluated for impairment	41,809		38,940
Total Loans	2,395,028		2,350,622
Consumer [Member]
Loans [Abstract]
Collectively evaluated for impairment	173		327
Individually evaluated for impairment	1,018		874
Total Allowance for Credit Losses - Loans for impairment	1,191	1,036	1,201	1,119	1,360	1,338
Collectively evaluated for impairment	38,596		87,301
Individually evaluated for impairment	1,027		909
Total Loans	39,623		88,210
Other Commercial Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	2,249		1,903
Individually evaluated for impairment	788		631
Total Allowance for Credit Losses - Loans for impairment	3,037	2,815	2,534	1,993	2,090	3,766
Collectively evaluated for impairment	172,738		171,343
Individually evaluated for impairment	8,259		7,823
Total Loans	180,997		179,166
Other Agricultural Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	164		115
Individually evaluated for impairment	26		0
Total Allowance for Credit Losses - Loans for impairment	190	223	115	132	137	133
Collectively evaluated for impairment	29,249		29,844
Individually evaluated for impairment	497		403
Total Loans	29,746		30,247
State and Political Subdivision Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	106		55
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	106	154	55	56	57	61
Collectively evaluated for impairment	88,468		52,100
Individually evaluated for impairment	0		0
Total Loans	88,468		52,100
Unallocated [Member]
Loans [Abstract]
Collectively evaluated for impairment	34		15
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	34	5	15	34	85	356
Collectively evaluated for impairment	0		0
Individually evaluated for impairment	0		0
Total Loans	0		0
Residential [Member]
Loans [Abstract]
Total Loans	285,390		288,664
Residential [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	2,626		3,050
Individually evaluated for impairment	45		62
Total Allowance for Credit Losses - Loans for impairment	2,671	2,741	3,112	3,062	3,213	1,940
Collectively evaluated for impairment	334,391		338,600
Individually evaluated for impairment	3,237		2,372
Total Loans	337,628		340,972
Commercial [Member]
Loans [Abstract]
Total Loans	1,267,682		1,218,514
Commercial [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	10,525		9,757
Individually evaluated for impairment	481		260
Total Allowance for Credit Losses - Loans for impairment	11,006	10,605	10,017	9,898	9,237	9,174
Collectively evaluated for impairment	1,242,249		1,193,742
Individually evaluated for impairment	25,433		24,772
Total Loans	1,267,682		1,218,514
Agricultural [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	4,411		4,841
Individually evaluated for impairment	0		0
Total Allowance for Credit Losses - Loans for impairment	4,411	4,513	4,841	4,542	4,350	3,529
Collectively evaluated for impairment	355,514		345,302
Individually evaluated for impairment	2,129		2,146
Total Loans	357,643		347,448
Construction [Member]
Loans [Abstract]
Total Loans	93,241		93,965
Construction [Member] \| Real Estate Loans [Member]
Loans [Abstract]
Collectively evaluated for impairment	839		830
Individually evaluated for impairment	74		86
Total Allowance for Credit Losses - Loans for impairment	913	$ 802	916	$ 1,273	$ 1,552	$ 1,402
Collectively evaluated for impairment	92,014		93,450
Individually evaluated for impairment	1,227		515
Total Loans	$ 93,241		$ 93,965