Loans and Allowance for Credit Losses - Allowance for Credit Losses Based on Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 70,182	$ 68,675	$ 68,675
Provision (release) for credit loss expense	1,652	(357)	5,635
Loans charged off	(2,083)	(819)	(5,748)
Recoveries collected	300	437	1,620
Allowance for credit losses, Ending Balance	70,051	67,936	70,182
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,275	2,918	2,918
Provision (release) for credit loss expense	456	(217)	352
Loans charged off	0	0	0
Recoveries collected	0	0	5
Allowance for credit losses, Ending Balance	3,731	2,701	3,275
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,361	1,366	1,366
Provision (release) for credit loss expense	(69)	(8)	(5)
Loans charged off	0	0	0
Recoveries collected	0	0	0
Allowance for credit losses, Ending Balance	1,292	1,358	1,361
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,579	4,220	4,220
Provision (release) for credit loss expense	(14)	(424)	(785)
Loans charged off	(39)	(67)	(195)
Recoveries collected	18	49	339
Allowance for credit losses, Ending Balance	3,544	3,778	3,579
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	32,669	31,758	31,758
Provision (release) for credit loss expense	(125)	618	1,178
Loans charged off	(338)	0	(451)
Recoveries collected	8	161	184
Allowance for credit losses, Ending Balance	32,214	32,537	32,669
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,957	705	705
Provision (release) for credit loss expense	809	125	3,587
Loans charged off	(1,117)	(52)	(2,410)
Recoveries collected	0	0	75
Allowance for credit losses, Ending Balance	1,649	778	1,957
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	25,602	25,450	25,450
Provision (release) for credit loss expense	559	(609)	510
Loans charged off	(223)	(274)	(688)
Recoveries collected	90	64	330
Allowance for credit losses, Ending Balance	26,028	24,631	25,602
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,739	2,258	2,258
Provision (release) for credit loss expense	36	158	798
Loans charged off	(366)	(426)	(2,004)
Recoveries collected	184	163	687
Allowance for credit losses, Ending Balance	$ 1,593	$ 2,153	$ 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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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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