v3.26.1
Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)
3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Aug. 31, 2025
Finite-Lived Intangible Assets [Line Items]            
Goodwill $ 1,482,000,000   $ 1,482,000,000   $ 1,482,000,000  
Finite-Lived Intangible Asset, Useful Life 10 years   10 years      
Goodwill and Intangible Asset Impairment     $ 0   $ 0  
Intangible amortization $ 38,000,000 $ 26,000,000 $ 79,000,000 $ 54,000,000    
Columbia Banking Systems and Pacific Premier Bancorp Merger            
Finite-Lived Intangible Assets [Line Items]            
Goodwill           $ 453,000,000