LHFI and ACL, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	$ 1,421	$ 1,154
Individually Evaluated for Credit Loss	32,490	24,854
Collectively Evaluated for Credit Loss	159,010	155,917
Collectively Evaluated for Credit Loss	13,845,481	13,649,379
Total LHFI	13,877,971	13,674,233
Total	160,431	157,071	$ 167,010	$ 160,270
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	1,139	811
Individually Evaluated for Credit Loss	3,192	1,804
Collectively Evaluated for Credit Loss	23,661	19,758
Collectively Evaluated for Credit Loss	2,163,233	1,997,660
Total LHFI	2,166,425	1,999,464
Total	24,800	20,569	25,396	27,020
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	95	103
Individually Evaluated for Credit Loss	95	103
Collectively Evaluated for Credit Loss	6,042	5,740
Collectively Evaluated for Credit Loss	159,348	163,651
Total LHFI	159,443	163,754
Total	6,137	5,843	5,238	5,141
State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	0
Individually Evaluated for Credit Loss	0	0
Collectively Evaluated for Credit Loss	773	865
Collectively Evaluated for Credit Loss	1,059,624	1,061,584
Total LHFI	1,059,624	1,061,584
Total	773	865	1,605	1,250
Other Commercial Loans and Leases [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	96	0
Individually Evaluated for Credit Loss	1,240	764
Collectively Evaluated for Credit Loss	8,967	8,009
Collectively Evaluated for Credit Loss	857,477	819,092
Total LHFI	858,717	819,856
Total	9,063	8,009	6,530	6,247
Loans Secured by Real Estate [Member] \| Construction, Land Development and Other Land [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	0
Individually Evaluated for Credit Loss	150	156
Collectively Evaluated for Credit Loss	7,257	6,632
Collectively Evaluated for Credit Loss	559,993	549,197
Total LHFI	560,143	549,353
Total	7,257	6,632	6,982	6,452
Loans Secured by Real Estate [Member] \| Other Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	91	99
Individually Evaluated for Credit Loss	542	848
Collectively Evaluated for Credit Loss	14,386	13,485
Collectively Evaluated for Credit Loss	711,990	703,666
Total LHFI	712,532	704,514
Total	14,477	13,584	12,476	11,347
Loans Secured by Real Estate [Member] \| Secured by Nonfarm, Nonresidential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	141
Individually Evaluated for Credit Loss	8,848	2,531
Collectively Evaluated for Credit Loss	31,093	35,042
Collectively Evaluated for Credit Loss	3,280,267	3,301,992
Total LHFI	3,289,115	3,304,523
Total	31,093	35,183	39,973	37,896
Loans Secured by Real Estate [Member] \| Other Real Estate Secured [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	15,234	15,234
Collectively Evaluated for Credit Loss	18,187	20,410
Collectively Evaluated for Credit Loss	2,063,988	2,109,038
Total LHFI	2,079,222	2,124,272
Total	18,187	20,410	23,348	19,491
Other Loans Secured by Real Estate [Member] \| Other Construction [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	0	0
Individually Evaluated for Credit Loss	0	0
Collectively Evaluated for Credit Loss	4,695	4,889
Collectively Evaluated for Credit Loss	645,555	595,238
Total LHFI	645,555	595,238
Total	4,695	4,889	9,860	13,297
Other Loans Secured by Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	3,189	3,414
Collectively Evaluated for Credit Loss	43,949	41,087
Collectively Evaluated for Credit Loss	2,344,006	2,348,261
Total LHFI	2,347,195	2,351,675
Total	$ 43,949	$ 41,087	$ 35,602	$ 32,129

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