Loans and Allowance for Credit Losses - Loan Portfolio by Categories (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 16,555,098	$ 16,142,124
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	331,407	349,810
Consumer | Credit cards
Loans and Leases Receivable Disclosure [Line Items]
Loans	188,590	196,928
Consumer | Other consumer
Loans and Leases Receivable Disclosure [Line Items]
Loans	142,817	152,882
Real Estate
Loans and Leases Receivable Disclosure [Line Items]
Loans	12,887,917	12,581,262
Real Estate | Construction and development
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,777,122	2,566,649
Real Estate | Single family residential
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,589,831	2,546,115
Real Estate | Other commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	7,520,964	7,468,498
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,890,372	2,837,913
Commercial | Commercial
Loans and Leases Receivable Disclosure [Line Items]
Loans	2,669,731	2,632,290
Commercial | Agricultural
Loans and Leases Receivable Disclosure [Line Items]
Loans	220,641	205,623
Other
Loans and Leases Receivable Disclosure [Line Items]
Loans	$ 445,402	$ 373,139