v3.26.1
Derivatives - Classification and Net Impact on Earnings of Derivatives (Details) - Derivatives not designated as hedging instruments - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Foreign currency forwards        
Derivative Instruments, Gain (Loss) [Line Items]        
Net impact on earnings $ (19.5) $ 33.4 $ (35.5) $ 74.3
Weather derivatives        
Derivative Instruments, Gain (Loss) [Line Items]        
Net impact on earnings 0.1 0.2 0.2 0.4
Interest rate swaps        
Derivative Instruments, Gain (Loss) [Line Items]        
Net impact on earnings 0.0 (0.3) 0.0 (0.5)
Reinsurance contracts accounted for as derivatives        
Derivative Instruments, Gain (Loss) [Line Items]        
Net impact on earnings $ (0.2) $ (0.1) $ (0.2) $ (0.1)