LHFI and ACL, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	$ 14,955		$ 17,687
Individually Evaluated for Credit Loss	47,378		40,288
Collectively Evaluated for Credit Loss	119,076		102,527
Collectively Evaluated for Credit Loss	12,762,881		12,163,751
Total LHFI	12,810,259		12,204,039
Total	134,031	$ 129,298	120,214	$ 115,050	$ 103,140	$ 99,457
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	9,118		9,946
Individually Evaluated for Credit Loss	9,232		24,594
Collectively Evaluated for Credit Loss	14,637		13,194
Collectively Evaluated for Credit Loss	1,819,692		1,796,665
Total LHFI	1,828,924		1,821,259
Total	23,755	23,170	23,140	24,104	14,103	18,939
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively Evaluated for Credit Loss	5,804		5,792
Collectively Evaluated for Credit Loss	165,556		170,230
Total LHFI	165,556		170,230
Total	5,804	5,540	5,792	5,028	5,139	4,774
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	665		885
Collectively Evaluated for Credit Loss	1,056,569		1,223,863
Total LHFI	1,056,569		1,223,863
Total	665	676	885	1,594	1,917	2,708
Other Commercial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	5,837		0
Individually Evaluated for Credit Loss	13,371		0
Collectively Evaluated for Credit Loss	4,853		4,647
Collectively Evaluated for Credit Loss	454,737		471,930
Total LHFI	468,108		471,930
Total	10,690	5,607	4,647	4,698	4,963	5,348
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		121
Individually Evaluated for Credit Loss	0		1,558
Collectively Evaluated for Credit Loss	17,241		12,707
Collectively Evaluated for Credit Loss	655,381		689,058
Total LHFI	655,381		690,616
Total	17,241	15,343	12,828	10,251	7,301	6,079
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	980		482
Collectively Evaluated for Credit Loss	12,563		12,374
Collectively Evaluated for Credit Loss	602,838		590,308
Total LHFI	603,818		590,790
Total	12,563	12,173	12,374	10,739	10,038	10,310
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	20,973		4,841
Collectively Evaluated for Credit Loss	23,298		19,488
Collectively Evaluated for Credit Loss	3,548,698		3,273,989
Total LHFI	3,569,671		3,278,830
Total	23,298	20,376	19,488	25,924	29,735	37,912
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	0		0
Collectively Evaluated for Credit Loss	3,565		4,743
Collectively Evaluated for Credit Loss	1,218,499		742,538
Total LHFI	1,218,499		742,538
Total	3,565	3,481	4,743	3,398	3,297	4,713
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		7,620
Individually Evaluated for Credit Loss	0		7,620
Collectively Evaluated for Credit Loss	6,306		7,512
Collectively Evaluated for Credit Loss	953,945		1,021,306
Total LHFI	953,945		1,028,926
Total	6,306	14,377	15,132	13,919	14,397	5,968
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	2,822		1,193
Collectively Evaluated for Credit Loss	30,144		21,185
Collectively Evaluated for Credit Loss	2,286,966		2,183,864
Total LHFI	2,289,788		2,185,057
Total	$ 30,144	$ 28,555	$ 21,185	$ 15,395	$ 12,250	$ 2,706