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, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 68,312	$ 58,719	$ 68,675	$ 59,093	$ 59,093
Initial allowance on loans purchased with credit deterioration		3,791		3,791	3,791
Provision for credit loss expense	1,266	5,911	1,992	5,552	6,104
Loans charged off	1,334	521	3,138	1,581	2,631
Recoveries collected	530	341	1,245	1,386	2,318
Allowance for credit losses, Ending Balance	68,774	68,241	68,774	68,241	68,675
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,646	2,208	2,918	2,250	2,250
Initial allowance on loans purchased with credit deterioration		308		308	308
Provision for credit loss expense	23	219	(249)	191	374
Loans charged off	0	0	0	14	14
Recoveries collected	5	0	5	0	0
Allowance for credit losses, Ending Balance	2,674	2,735	2,674	2,735	2,918
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,372	1,370	1,366	1,433	1,433
Initial allowance on loans purchased with credit deterioration		0		0	0
Provision for credit loss expense	(30)	27	(24)	(36)	(67)
Loans charged off	0	0	0	0	0
Recoveries collected	0	0	0	0	0
Allowance for credit losses, Ending Balance	1,342	1,397	1,342	1,397	1,366
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,580	3,247	4,220	3,742	3,742
Initial allowance on loans purchased with credit deterioration		124		124	124
Provision for credit loss expense	55	629	(633)	88	225
Loans charged off	42	21	143	77	87
Recoveries collected	88	91	237	193	216
Allowance for credit losses, Ending Balance	3,681	4,070	3,681	4,070	4,220
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	32,918	28,014	31,758	28,157	28,157
Initial allowance on loans purchased with credit deterioration		1,066		1,066	1,066
Provision for credit loss expense	349	2,727	1,343	2,278	1,755
Loans charged off	451	0	451	25	25
Recoveries collected	9	16	175	347	805
Allowance for credit losses, Ending Balance	32,825	31,823	32,825	31,823	31,758
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	885	524	705	585	585
Initial allowance on loans purchased with credit deterioration		0		0	0
Provision for credit loss expense	(50)	245	391	450	490
Loans charged off	0	132	261	408	408
Recoveries collected	25	3	25	13	38
Allowance for credit losses, Ending Balance	860	640	860	640	705
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	24,931	21,544	25,450	20,808	20,808
Initial allowance on loans purchased with credit deterioration		2,273		2,273	2,273
Provision for credit loss expense	542	1,697	557	2,202	2,322
Loans charged off	1	0	643	62	529
Recoveries collected	97	81	205	374	576
Allowance for credit losses, Ending Balance	25,569	25,595	25,569	25,595	25,450
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,980	1,812	2,258	2,118	2,118
Initial allowance on loans purchased with credit deterioration		20		20	20
Provision for credit loss expense	377	367	607	379	1,005
Loans charged off	840	368	1,640	995	1,568
Recoveries collected	306	150	598	459	683
Allowance for credit losses, Ending Balance	$ 1,823	$ 1,981	$ 1,823	$ 1,981	$ 2,258

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- Definition

Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

+ References

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-Topic 326
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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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