LHFI and ACL, LHFI - Summary of Balance in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	$ 17,902	$ 17,687
Individually Evaluated for Credit Loss	39,853	40,288
Collectively Evaluated for Credit Loss	104,337	102,527
Collectively Evaluated for Credit Loss	12,457,342	12,163,751
Total LHFI	12,497,195	12,204,039
Total	122,239	120,214	$ 98,734	$ 99,457
Commercial and Industrial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	9,290	9,946
Individually Evaluated for Credit Loss	23,501	24,594
Collectively Evaluated for Credit Loss	14,172	13,194
Collectively Evaluated for Credit Loss	1,890,636	1,796,665
Total LHFI	1,914,137	1,821,259
Total	23,462	23,140	14,951	18,939
Consumer Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Collectively Evaluated for Credit Loss	5,532	5,792
Collectively Evaluated for Credit Loss	166,464	170,230
Total LHFI	166,464	170,230
Total	5,532	5,792	4,872	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	729	885
Collectively Evaluated for Credit Loss	1,193,727	1,223,863
Total LHFI	1,193,727	1,223,863
Total	729	885	2,371	2,708
Other Commercial Loans [Member]
Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract]
Individually Evaluated for Credit Loss	879	0
Individually Evaluated for Credit Loss	879	0
Collectively Evaluated for Credit Loss	4,831	4,647
Collectively Evaluated for Credit Loss	453,062	471,930
Total LHFI	453,941	471,930
Total	5,710	4,647	4,077	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	113	121
Individually Evaluated for Credit Loss	1,540	1,558
Collectively Evaluated for Credit Loss	13,147	12,707
Collectively Evaluated for Credit Loss	680,674	689,058
Total LHFI	682,214	690,616
Total	13,260	12,828	7,351	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	473	482
Collectively Evaluated for Credit Loss	11,918	12,374
Collectively Evaluated for Credit Loss	595,047	590,308
Total LHFI	595,520	590,790
Total	11,918	12,374	9,867	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	4,168	4,841
Collectively Evaluated for Credit Loss	18,640	19,488
Collectively Evaluated for Credit Loss	3,371,411	3,273,989
Total LHFI	3,375,579	3,278,830
Total	18,640	19,488	32,030	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
Collectively Evaluated for Credit Loss	2,362	4,743
Collectively Evaluated for Credit Loss	847,527	742,538
Total LHFI	847,527	742,538
Total	2,362	4,743	3,640	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	7,620	7,620
Individually Evaluated for Credit Loss	7,620	7,620
Collectively Evaluated for Credit Loss	6,850	7,512
Collectively Evaluated for Credit Loss	1,033,938	1,021,306
Total LHFI	1,041,558	1,028,926
Total	14,470	15,132	13,947	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	1,672	1,193
Collectively Evaluated for Credit Loss	26,156	21,185
Collectively Evaluated for Credit Loss	2,224,856	2,183,864
Total LHFI	2,226,528	2,185,057
Total	$ 26,156	$ 21,185	$ 5,628	$ 2,706

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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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