v3.26.1
Goodwill and Core Deposit Intangibles - Goodwill and Core Deposit Intangibles (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Finite-Lived Intangible Assets [Line Items]      
Goodwill, Beginning balance $ 3,503,127 $ 3,503,129 $ 3,503,129
Goodwill, Ending balance 3,822,283   3,503,127
Core Deposit Intangibles, Beginning balance 51,605 66,047 66,047
Core Deposit Intangibles, Amortization (5,259) $ (3,641) (14,442)
Core Deposit Intangibles, Ending balance 111,243   51,605
Lone Star Merger [Member]      
Finite-Lived Intangible Assets [Line Items]      
Goodwill, Measurement period adjustment     $ (2)
American Merger [Member]      
Finite-Lived Intangible Assets [Line Items]      
Goodwill, Merger 185,042    
Core Deposit Intangibles, Merger 31,103    
Southwest Merger [Member]      
Finite-Lived Intangible Assets [Line Items]      
Goodwill, Merger 134,114    
Core Deposit Intangibles, Merger $ 33,794