Loans and Allowance for Credit Losses - Loan Portfolio by Categories (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 15,607,135	$ 12,012,503
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	373,163	355,370
Consumer | Credit cards
Loans and Leases Receivable Disclosure [Line Items]
Loans	192,559	187,052
Consumer | Other consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	180,604	168,318
Real Estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	12,089,193	9,167,250
Real Estate | Construction and development
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,372,294	1,326,371
Real Estate | Single family residential
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,467,008	2,101,975
Real Estate | Other commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	7,249,891	5,738,904
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,788,757	2,160,760
Commercial | Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,525,218	1,992,043
Commercial | Agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	263,539	168,717
Other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 356,022	$ 329,123