LHFI and ACL, LHFI - Aging Analysis of Past Due and Nonaccrual LHFI by Loan Type (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	$ 13,057,943	$ 12,950,524
Total LHFI	13,057,943	12,950,524
30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	38,219	40,995
Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	24,249	13,898
Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	49,406	29,322
Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	111,874	84,215
Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	12,946,069	12,866,309
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	617,008	642,886
Total LHFI	617,008	642,886
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	354	93
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	590	507
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,011	2,362
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,955	2,962
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	615,053	639,924
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	625,387	622,397
Total LHFI	625,387	622,397
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	6,147	4,493
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,554	1,687
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,575	2,716
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	10,276	8,896
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	615,111	613,501
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,266,094	2,282,318
Total LHFI	2,266,094	2,282,318
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	14,706	19,298
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	7,246	9,327
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	25,361	22,164
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	47,313	50,789
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,218,781	2,231,529
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	3,543,235	3,489,434
Total LHFI	3,543,235	3,489,434
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	695	1,531
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	711	1,063
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	892	727
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,298	3,321
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	3,540,937	3,486,113
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,384,610	1,312,551
Total LHFI	1,384,610	1,312,551
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	126
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	207
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	333
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,384,610	1,312,218
Commercial and Industrial Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,922,711	1,922,910
Total LHFI	1,922,711	1,922,910
Commercial and Industrial Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	12,207	11,881
Commercial and Industrial Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	446	484
Commercial and Industrial Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	19,018	499
Commercial and Industrial Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	31,671	12,864
Commercial and Industrial Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,891,040	1,910,046
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Total LHFI	922,453	867,793
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	62
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	13,038	0
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	13,038	62
Other Construction Financing Receivable [Member] | Other Loans Secured by Real Estate [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	909,415	867,731
Consumer Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	159,340	165,734
Total LHFI	159,340	165,734
Consumer Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,616	2,112
Consumer Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	548	772
Consumer Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	512	647
Consumer Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	2,676	3,531
Consumer Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	156,664	162,203
State and Other Political Subdivision Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,052,844	1,088,466
Total LHFI	1,052,844	1,088,466
State and Other Political Subdivision Loans [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	972	152
State and Other Political Subdivision Loans [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
State and Other Political Subdivision Loans [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	0	0
State and Other Political Subdivision Loans [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	972	152
State and Other Political Subdivision Loans [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,051,872	1,088,314
Other Commercial Loans and Leases [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	564,261	556,035
Total LHFI	564,261	556,035
Other Commercial Loans and Leases [Member] | 30 Days or More Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,522	1,247
Other Commercial Loans and Leases [Member] | Past Due 60 to 89 Days [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	116	58
Other Commercial Loans and Leases [Member] | Past Due 90 Days or More [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	37	0
Other Commercial Loans and Leases [Member] | Financial Asset, Past Due [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	1,675	1,305
Other Commercial Loans and Leases [Member] | Current Loans
Financing Receivable Allowance For Credit Losses [Line Items]
Loans held for investment (LHFI)	$ 562,586	$ 554,730