v3.25.3
Fair Value Disclosures - Summary of the Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($)
$ in Thousands
Sep. 30, 2025
Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Available-for-sale debt securities $ 3,801,261 $ 3,524,686
Held-to-maturity debt securities 743,120 796,168
Equity securities 55,054 75,261
Trading securities 2,219 0
Derivative assets 37,297 23,202
Long-term debt 620,416 660,346
Derivative liabilities 24,264 57,906
Carrying Amount    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 3,064,825 3,188,808
Available-for-sale debt securities 3,801,261 3,524,686
Held-to-maturity debt securities 743,120 796,168
Equity securities 55,054 75,261
Trading securities 2,219  
Loans held for investment, net 23,917,837 22,178,357
Derivative assets 37,297 23,202
Total deposits 27,505,398 25,238,599
Short-term borrowings 275,000 885,000
Long-term debt 620,416 660,346
Securities sold not yet purchased 24,730 33,705
Derivative liabilities 24,264 57,906
Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 3,064,825 3,188,808
Available-for-sale debt securities 3,801,261 3,524,686
Held-to-maturity debt securities 661,923 678,174
Equity securities 55,054 75,261
Trading securities 2,219  
Loans held for investment, net 23,874,493 22,115,585
Derivative assets 37,297 23,202
Total deposits 27,504,235 25,245,009
Short-term borrowings 275,000 885,000
Long-term debt 592,312 622,713
Securities sold not yet purchased 24,730 33,705
Derivative liabilities 24,264 57,906
Level 1 | Estimated Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]    
Cash and cash equivalents 3,064,825 3,188,808
Available-for-sale debt securities 0 277,285
Held-to-maturity debt securities 0 0
Equity securities 45,054 59,235
Trading securities 0  
Loans held for investment, net 0 0
Derivative assets 0 0
Total deposits 0 0
Short-term borrowings 0 0
Long-term debt 0 0
Securities sold not yet purchased 24,730 33,705
Derivative liabilities 0 0
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 3,790,268 3,235,475
Held-to-maturity debt securities 661,923 678,174
Equity securities 10,000 16,026
Trading securities 2,219  
Loans held for investment, net 0 0
Derivative assets 37,297 23,202
Total deposits 0 0
Short-term borrowings 275,000 885,000
Long-term debt 592,312 622,713
Securities sold not yet purchased 0 0
Derivative liabilities 24,264 57,906
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 10,993 11,926
Held-to-maturity debt securities 0 0
Equity securities 0 0
Trading securities 0  
Loans held for investment, net 23,874,493 22,115,585
Derivative assets 0 0
Total deposits 27,504,235 25,245,009
Short-term borrowings 0 0
Long-term debt 0 0
Securities sold not yet purchased 0 0
Derivative liabilities $ 0 $ 0