Loans and Allowance for Credit Losses - Allowance for Credit Losses Based on Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 71,160	$ 68,312	$ 70,182	$ 68,675	$ 68,675
Provision (release) for credit loss expense	3,353	1,266	7,572	1,992	5,635
Loans charged off	(2,091)	(1,334)	(6,435)	(3,138)	(5,748)
Recoveries collected	503	530	1,606	1,245	1,620
Allowance for credit losses, Ending Balance	72,925	68,774	72,925	68,774	70,182
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	4,066	2,646	3,275	2,918	2,918
Provision (release) for credit loss expense	727	(23)	1,518	(249)	352
Loans charged off	(107)	0	(107)	0	0
Recoveries collected	0	5	0	5	5
Allowance for credit losses, Ending Balance	4,686	2,674	4,686	2,674	3,275
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,322	1,372	1,361	1,366	1,366
Provision (release) for credit loss expense	(110)	(30)	(149)	(24)	(5)
Loans charged off	0	0	0	0	0
Recoveries collected	53	0	53	0	0
Allowance for credit losses, Ending Balance	1,265	1,342	1,265	1,342	1,361
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,616	3,580	3,579	4,220	4,220
Provision (release) for credit loss expense	29	55	8	(633)	(785)
Loans charged off	(1)	(42)	(95)	(143)	(195)
Recoveries collected	78	88	230	237	339
Allowance for credit losses, Ending Balance	3,722	3,681	3,722	3,681	3,579
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	33,258	32,918	32,669	31,758	31,758
Provision (release) for credit loss expense	1,655	349	2,641	1,343	1,178
Loans charged off	(699)	(451)	(1,107)	(451)	(451)
Recoveries collected	5	9	16	175	184
Allowance for credit losses, Ending Balance	34,219	32,825	34,219	32,825	32,669
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,767	885	1,957	705	705
Provision (release) for credit loss expense	(353)	(50)	1,743	391	3,587
Loans charged off	0	0	(2,503)	(261)	(2,410)
Recoveries collected	198	25	415	25	75
Allowance for credit losses, Ending Balance	1,612	860	1,612	860	1,957
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	25,618	24,931	25,602	25,450	25,450
Provision (release) for credit loss expense	1,222	542	1,578	557	510
Loans charged off	(942)	(1)	(1,654)	(643)	(688)
Recoveries collected	66	97	438	205	330
Allowance for credit losses, Ending Balance	25,964	25,569	25,964	25,569	25,602
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,513	1,980	1,739	2,258	2,258
Provision (release) for credit loss expense	183	377	233	607	798
Loans charged off	(342)	(840)	(969)	(1,640)	(2,004)
Recoveries collected	103	306	454	598	687
Allowance for credit losses, Ending Balance	$ 1,457	$ 1,823	$ 1,457	$ 1,823	$ 1,739

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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