Allowance for Credit Losses on Loans - Summary of Changes in Allowance for Loan Losses, by Portfolio Type (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	$ 30,926	$ 23,518	$ 23,518
ASC 326 Adoption Day 1 Adjustment		8,120
Charge-offs	(2,285)	(973)	(5,771)
Recoveries	255	489
Provision	2,554	314
Ending allowance	31,450	31,468	30,926
Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	24,744	13,102	13,102
ASC 326 Adoption Day 1 Adjustment		7,042
Charge-offs	(41)	(171)
Recoveries	12	37
Provision	(134)	1,781
Ending allowance	24,581	21,791	24,744
Real Estate \| Construction & land development
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	5,845	1,232	1,232
ASC 326 Adoption Day 1 Adjustment		1,891
Charge-offs	0	0	0
Recoveries	1	0
Provision	(1,016)	779
Ending allowance	4,830	3,902	5,845
Real Estate \| Farmland
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	36	83	83
ASC 326 Adoption Day 1 Adjustment		(39)
Charge-offs	0	0	0
Recoveries	0	0
Provision	27	(6)
Ending allowance	63	38	36
Real Estate \| 1- 4 family
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	6,653	1,761	1,761
ASC 326 Adoption Day 1 Adjustment		3,465
Charge-offs	(41)	(33)	(964)
Recoveries	3	3
Provision	(20)	253
Ending allowance	6,595	5,449	6,653
Real Estate \| Multifamily
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	1,614	746	746
ASC 326 Adoption Day 1 Adjustment		1,418
Charge-offs	0	0	0
Recoveries	0	0
Provision	163	194
Ending allowance	1,777	2,358	1,614
Real Estate \| Non-farm non-residential
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	10,596	9,280	9,280
ASC 326 Adoption Day 1 Adjustment		307
Charge-offs	0	(138)	(138)
Recoveries	8	34
Provision	712	561
Ending allowance	11,316	10,044	10,596
Non-Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	6,182	10,416	10,416
ASC 326 Adoption Day 1 Adjustment		1,078
Charge-offs	(2,244)	(802)
Recoveries	243	452
Provision	2,688	(1,467)
Ending allowance	6,869	9,677	6,182
Non-Real Estate \| Agricultural
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	97	240	240
ASC 326 Adoption Day 1 Adjustment		(98)
Charge-offs	(33)	0	0
Recoveries	10	167
Provision	46	(166)
Ending allowance	120	143	97
Non-Real Estate \| Commercial and industrial
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	2,711	2,194	2,194
ASC 326 Adoption Day 1 Adjustment		2,971
Charge-offs	(627)	(44)	(1,694)
Recoveries	115	154
Provision	1,684	(1,021)
Ending allowance	3,883	4,254	2,711
Non-Real Estate \| Commercial leases
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	1,948	4,879	4,879
ASC 326 Adoption Day 1 Adjustment		(162)
Charge-offs	0	0	0
Recoveries	0	0
Provision	(564)	(2,280)
Ending allowance	1,384	2,437	1,948
Non-Real Estate \| Consumer and other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	1,426	2,506	2,506
ASC 326 Adoption Day 1 Adjustment		(1,042)
Charge-offs	(1,584)	(758)	(2,975)
Recoveries	118	131
Provision	1,522	860
Ending allowance	1,482	1,697	1,426
Non-Real Estate \| Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning allowance	0	597	597
ASC 326 Adoption Day 1 Adjustment		(591)
Charge-offs	0	0
Recoveries	0	0
Provision	0	1,140
Ending allowance	$ 0	$ 1,146	$ 0

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable from change in methodology. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-11

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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