Loans and Allowance for Credit Losses - Allowance for Credit Losses Based on Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 67,936	$ 58,223	$ 68,675	$ 59,093	$ 59,093
Initial allowance on loans purchased with credit deterioration					3,791
Provision for credit loss expense	1,083	458	726	(359)	6,104
Loans charged off	985	580	1,804	1,060	2,631
Recoveries collected	278	618	715	1,045	2,318
Allowance for credit losses, Ending Balance	68,312	58,719	68,312	58,719	68,675
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,701	2,426	2,918	2,250	2,250
Initial allowance on loans purchased with credit deterioration					308
Provision for credit loss expense	(55)	(204)	(272)	(28)	374
Loans charged off	0	14	0	14	14
Recoveries collected	0	0	0	0	0
Allowance for credit losses, Ending Balance	2,646	2,208	2,646	2,208	2,918
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,358	1,404	1,366	1,433	1,433
Initial allowance on loans purchased with credit deterioration					0
Provision for credit loss expense	14	(34)	6	(63)	(67)
Loans charged off	0	0	0	0	0
Recoveries collected	0	0	0	0	0
Allowance for credit losses, Ending Balance	1,372	1,370	1,372	1,370	1,366
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,778	3,420	4,220	3,742	3,742
Initial allowance on loans purchased with credit deterioration					124
Provision for credit loss expense	(264)	(235)	(688)	(541)	225
Loans charged off	34	16	101	56	87
Recoveries collected	100	78	149	102	216
Allowance for credit losses, Ending Balance	3,580	3,247	3,580	3,247	4,220
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	32,537	27,327	31,758	28,157	28,157
Initial allowance on loans purchased with credit deterioration					1,066
Provision for credit loss expense	376	385	994	(449)	1,755
Loans charged off	0	25	0	25	25
Recoveries collected	5	327	166	331	805
Allowance for credit losses, Ending Balance	32,918	28,014	32,918	28,014	31,758
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	778	580	705	585	585
Initial allowance on loans purchased with credit deterioration					0
Provision for credit loss expense	316	213	441	205	490
Loans charged off	209	276	261	276	408
Recoveries collected	0	7	0	10	38
Allowance for credit losses, Ending Balance	885	524	885	524	705
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	24,631	21,142	25,450	20,808	20,808
Initial allowance on loans purchased with credit deterioration					2,273
Provision for credit loss expense	624	414	15	505	2,322
Loans charged off	368	49	642	62	529
Recoveries collected	44	37	108	293	576
Allowance for credit losses, Ending Balance	24,931	21,544	24,931	21,544	25,450
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,153	1,924	2,258	2,118	2,118
Initial allowance on loans purchased with credit deterioration					20
Provision for credit loss expense	72	(81)	230	12	1,005
Loans charged off	374	200	800	627	1,568
Recoveries collected	129	169	292	309	683
Allowance for credit losses, Ending Balance	$ 1,980	$ 1,812	$ 1,980	$ 1,812	$ 2,258

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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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