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, 2023	Mar. 31, 2022	Dec. 31, 2022
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	$ 59,093	$ 54,655	$ 54,655
Initial allowance on loans purchased with credit deterioration	0	863
Provision for credit loss expense	(817)	2,952	4,806
Loans charged off	480	774	2,950
Recoveries collected	427	778	1,719
Allowance for credit losses, Ending Balance	58,223	58,474	59,093
Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		863	863
Construction and Land Development \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,250	1,743	1,743
Initial allowance on loans purchased with credit deterioration	0	272
Provision for credit loss expense	176	(25)	137
Loans charged off	0	2	2
Recoveries collected	0	0	100
Allowance for credit losses, Ending Balance	2,426	1,988	2,250
Construction and Land Development \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		272	272
Agricultural \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	1,433	1,257	1,257
Initial allowance on loans purchased with credit deterioration	0	0
Provision for credit loss expense	(29)	714	176
Loans charged off	0	0	0
Recoveries collected	0	0	0
Allowance for credit losses, Ending Balance	1,404	1,971	1,433
Agricultural \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		0	0
Residential Properties \| Real Estate Loan \| 1-4 Family
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	3,742	2,330	2,330
Initial allowance on loans purchased with credit deterioration	0	3
Provision for credit loss expense	(306)	1,264	1,241
Loans charged off	40	72	191
Recoveries collected	24	203	359
Allowance for credit losses, Ending Balance	3,420	3,728	3,742
Residential Properties \| Real Estate Loan \| 1-4 Family \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		3	3
Commercial \| Real Estate Loan
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	28,157	26,246	26,246
Initial allowance on loans purchased with credit deterioration	0	478
Provision for credit loss expense	(834)	3,613	1,462
Loans charged off	0	339	414
Recoveries collected	4	347	385
Allowance for credit losses, Ending Balance	27,327	30,345	28,157
Commercial \| Real Estate Loan \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		478	478
Agricultural Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	585	983	983
Initial allowance on loans purchased with credit deterioration	0	0
Provision for credit loss expense	(8)	68	(359)
Loans charged off	0	0	93
Recoveries collected	3	0	54
Allowance for credit losses, Ending Balance	580	1,051	585
Agricultural Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		0	0
Commercial and Industrial Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	20,808	19,241	19,241
Initial allowance on loans purchased with credit deterioration	0	94
Provision for credit loss expense	91	(2,045)	2,135
Loans charged off	13	3	870
Recoveries collected	256	61	208
Allowance for credit losses, Ending Balance	21,142	17,348	20,808
Commercial and Industrial Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		94	94
Consumer Loans
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance	2,118	2,855	2,855
Initial allowance on loans purchased with credit deterioration	0	16
Provision for credit loss expense	93	(637)	14
Loans charged off	427	358	1,380
Recoveries collected	140	167	613
Allowance for credit losses, Ending Balance	$ 1,924	2,043	2,118
Consumer Loans \| Cumulative Change in Accounting Principal, Adjustment \| ASU 2016-13
Allowance for loan losses [Abstract]
Allowance for credit losses, Beginning Balance		$ 16	$ 16

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

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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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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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