Loans, Allowance for Credit Losses - Loans and Amortized Cost Basis of Loans Under CECL Methodology (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024	Dec. 31, 2023
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	$ 20,478	$ 19,796
Individually evaluated for impairment	1,603	1,903
Total Allowance for Credit Losses - Loans for impairment	22,081	21,699	$ 21,598	$ 21,153
Collectively evaluated for impairment	2,289,830	2,287,674
Individually evaluated for impairment	25,833	25,568
Total Loans	2,315,663	2,313,242
Residential [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Total Loans	301,170	301,735
Commercial [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Total Loans	1,117,240	1,121,435
Construction [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Total Loans	168,896	164,326
Real Estate Loans [Member] \| Residential [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	3,184	1,902
Individually evaluated for impairment	29	38
Total Allowance for Credit Losses - Loans for impairment	3,213	1,940	2,347	2,354
Collectively evaluated for impairment	348,768	349,909
Individually evaluated for impairment	1,453	1,489
Total Loans	350,221	351,398
Real Estate Loans [Member] \| Commercial [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	9,150	9,070
Individually evaluated for impairment	87	104
Total Allowance for Credit Losses - Loans for impairment	9,237	9,174	9,741	9,178
Collectively evaluated for impairment	1,102,159	1,105,847
Individually evaluated for impairment	15,081	15,588
Total Loans	1,117,240	1,121,435
Real Estate Loans [Member] \| Agricultural [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	4,350	3,529
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans for impairment	4,350	3,529	3,672	3,264
Collectively evaluated for impairment	326,283	323,660
Individually evaluated for impairment	3,702	4,062
Total Loans	329,985	327,722
Real Estate Loans [Member] \| Construction [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	1,552	1,402
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans for impairment	1,552	1,402	1,595	1,950
Collectively evaluated for impairment	167,494	164,043
Individually evaluated for impairment	1,402	283
Total Loans	168,896	164,326
Consumer [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	422	391
Individually evaluated for impairment	996	1,014
Total Allowance for Credit Losses - Loans for impairment	1,418	1,405	1,266	1,496
Collectively evaluated for impairment	128,943	132,180
Individually evaluated for impairment	1,000	1,027
Total Loans	129,943	133,207
Other Commercial Loans [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	1,541	2,952
Individually evaluated for impairment	491	747
Total Allowance for Credit Losses - Loans for impairment	2,032	3,699	2,680	2,229
Collectively evaluated for impairment	134,745	128,728
Individually evaluated for impairment	2,784	2,582
Total Loans	137,529	131,310
Other Agricultural Loans [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	137	133
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans for impairment	137	133	174	270
Collectively evaluated for impairment	28,077	29,125
Individually evaluated for impairment	411	537
Total Loans	28,488	29,662
State and Political Subdivision Loans [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	57	61
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans for impairment	57	61	65	45
Collectively evaluated for impairment	53,361	54,182
Individually evaluated for impairment	0	0
Total Loans	53,361	54,182
Unallocated [Member]
Loans And Leases Receivable, Allowance For Loan Losses [Abstract]
Collectively evaluated for impairment	85	356
Individually evaluated for impairment	0	0
Total Allowance for Credit Losses - Loans for impairment	85	356	$ 58	$ 367
Collectively evaluated for impairment	0	0
Individually evaluated for impairment	0	0
Total Loans	$ 0	$ 0

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