v3.26.1
Fair Value Disclosures - Summary of the Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Available-for-sale debt securities $ 3,913,855 $ 3,951,455
Held-to-maturity debt securities 709,594 725,722
Equity securities 42,024 41,998
Trading debt securities 7,882 3,924
Derivative assets 43,918 40,892
Long-term debt 878,293 620,575
Derivative liabilities 41,578 24,458
Carrying Amount    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 2,956,611 2,099,118
Available-for-sale debt securities 3,913,855 3,951,455
Held-to-maturity debt securities 709,594 725,722
Equity securities 42,024 41,998
Trading debt securities 7,882 3,924
Loans held for sale 21,333 4,361
Loans held for investment, net 24,909,221 23,769,645
Derivative assets 43,918 40,892
Other trading assets 72  
Total deposits 28,516,688 26,448,767
Short-term borrowings   330,000
Long-term debt 878,293 620,575
Securities sold not yet purchased 12,503 12,026
Derivative liabilities 41,578 24,458
Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 2,956,611 2,099,118
Available-for-sale debt securities 3,913,855 3,951,455
Held-to-maturity debt securities 638,584 654,832
Equity securities 42,024 41,998
Trading debt securities 7,882 3,924
Loans held for sale 21,333 4,361
Loans held for investment, net 24,699,883 23,604,206
Derivative assets 43,918 40,892
Other trading assets 72  
Total deposits 28,524,120 26,450,932
Short-term borrowings   330,000
Long-term debt 849,030 593,610
Securities sold not yet purchased 12,503 12,026
Derivative liabilities 41,578 24,458
Level 1    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Equity securities 32,024 31,998
Trading debt securities 0 0
Loans held for investment, net 0 0
Derivative assets 0 0
Other trading assets 72  
Securities sold not yet purchased 12,503 12,026
Derivative liabilities 0 0
Level 1 | Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 2,956,611 2,099,118
Available-for-sale debt securities 0 0
Held-to-maturity debt securities 0 0
Equity securities 32,024 31,998
Trading debt securities 0 0
Loans held for sale 0
Loans held for investment, net 0 0
Derivative assets 0 0
Other trading assets 72  
Total deposits 0 0
Short-term borrowings   0
Long-term debt 0 0
Securities sold not yet purchased 12,503 12,026
Derivative liabilities 0 0
Level 2    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Equity securities 10,000 10,000
Trading debt securities 7,882 3,924
Loans held for investment, net 0 0
Derivative assets 43,918 40,892
Other trading assets 0  
Securities sold not yet purchased 0 0
Derivative liabilities 41,578 24,458
Level 2 | Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 0 0
Available-for-sale debt securities 3,903,281 3,940,658
Held-to-maturity debt securities 638,584 654,832
Equity securities 10,000 10,000
Trading debt securities 7,882 3,924
Loans held for sale 21,333 4,361
Loans held for investment, net 0 0
Derivative assets 43,918 40,892
Other trading assets 0  
Total deposits 0 0
Short-term borrowings   330,000
Long-term debt 849,030 593,610
Securities sold not yet purchased 0 0
Derivative liabilities 41,578 24,458
Level 3    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Equity securities 0 0
Trading debt securities 0 0
Loans held for investment, net 52,228 20,844
Derivative assets 0 0
Other trading assets 0  
Securities sold not yet purchased 0 0
Derivative liabilities 0 0
Level 3 | Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 0 0
Available-for-sale debt securities 10,574 10,797
Held-to-maturity debt securities 0 0
Equity securities 0 0
Trading debt securities 0 0
Loans held for sale 0
Loans held for investment, net 24,699,883 23,604,206
Derivative assets 0 0
Other trading assets 0  
Total deposits 28,524,120 26,450,932
Short-term borrowings   0
Long-term debt 0 0
Securities sold not yet purchased 0 0
Derivative liabilities $ 0 $ 0