LHFI and ACL, LHFI - Loan Portfolio Held for Investment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Loan Portfolio [Abstract]
Total LHFI	$ 12,204,039	$ 10,247,829
Less ACL, LHFI	120,214	99,457	$ 117,306	$ 84,277
Net LHFI	12,083,825	10,148,372
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	690,616	596,968
Other Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	590,790	517,683
Secured by 1-4 Family Residential Properties [Member] | Other Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	2,185,057	1,460,310
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	742,538	726,043
Other Construction [Member] | Other Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	1,028,926	711,813
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member]
Loan Portfolio [Abstract]
Total LHFI	3,278,830	2,977,084
Less ACL, LHFI	19,488	37,912	48,523
Commercial and Industrial Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	1,821,259	1,414,279
Less ACL, LHFI	23,140	18,939	14,851
Consumer Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	170,230	162,555
Less ACL, LHFI	5,792	4,774	5,838
State and Other Political Subdivision Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	1,223,863	1,146,251
Less ACL, LHFI	885	2,708	3,190
Other Commercial Loans [Member]
Loan Portfolio [Abstract]
Total LHFI	471,930	534,843
Less ACL, LHFI	$ 4,647	$ 5,348	$ 7,439