LHFI and ACL, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	$ 17,687	$ 7,625
Individually Evaluated for Credit Loss	40,288	44,361
Collectively Evaluated for Credit Loss	102,527	91,832
Collectively Evaluated for Credit Loss	12,163,751	10,203,468
Total LHFI	12,204,039	10,247,829
Total	120,214	99,457	$ 117,306	$ 84,277
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	9,946	5,750
Individually Evaluated for Credit Loss	24,594	18,444
Collectively Evaluated for Credit Loss	13,194	13,189
Collectively Evaluated for Credit Loss	1,796,665	1,395,835
Total LHFI	1,821,259	1,414,279
Total	23,140	18,939	14,851
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively Evaluated for Credit Loss	5,792	4,774
Collectively Evaluated for Credit Loss	170,230	162,555
Total LHFI	170,230	162,555
Total	5,792	4,774	5,838
State and Other Political Subdivision Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss		1,394
Individually Evaluated for Credit Loss		3,664
Collectively Evaluated for Credit Loss	885	1,314
Collectively Evaluated for Credit Loss	1,223,863	1,142,587
Total LHFI	1,223,863	1,146,251
Total	885	2,708	3,190
Other Commercial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss		203
Individually Evaluated for Credit Loss		4,608
Collectively Evaluated for Credit Loss	4,647	5,145
Collectively Evaluated for Credit Loss	471,930	530,235
Total LHFI	471,930	534,843
Total	4,647	5,348	7,439
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	121	278
Individually Evaluated for Credit Loss	1,558	5,198
Collectively Evaluated for Credit Loss	12,707	5,801
Collectively Evaluated for Credit Loss	689,058	591,770
Total LHFI	690,616	596,968
Total	12,828	6,079	6,854
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	482
Collectively Evaluated for Credit Loss	12,374	10,310
Collectively Evaluated for Credit Loss	590,308	517,683
Total LHFI	590,790	517,683
Total	12,374	10,310	9,928
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	4,841	11,072
Collectively Evaluated for Credit Loss	19,488	37,912
Collectively Evaluated for Credit Loss	3,273,989	2,966,012
Total LHFI	3,278,830	2,977,084
Total	19,488	37,912	48,523
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		56
Collectively Evaluated for Credit Loss	4,743	4,713
Collectively Evaluated for Credit Loss	742,538	725,987
Total LHFI	742,538	726,043
Total	4,743	4,713	7,382
Other Loans Secured by Real Estate [Member] \| Other Construction [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	7,620
Individually Evaluated for Credit Loss	7,620
Collectively Evaluated for Credit Loss	7,512	5,968
Collectively Evaluated for Credit Loss	1,021,306	711,813
Total LHFI	1,028,926	711,813
Total	15,132	5,968	8,158
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	1,193	1,319
Collectively Evaluated for Credit Loss	21,185	2,706
Collectively Evaluated for Credit Loss	2,183,864	1,458,991
Total LHFI	2,185,057	1,460,310
Total	$ 21,185	$ 2,706	$ 5,143

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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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