v3.26.1
Derivative Contracts - Gain/(Loss) Recognized in Income on Derivative (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Not Designated as Hedging Instrument | Foreign exchange contracts    
Derivative Instruments, Gain (Loss) [Line Items]    
Gain (loss) to net income from derivative instruments $ 43.9 $ (34.0)
Not Designated as Hedging Instrument | Loss portfolio transfer liability, embedded derivative    
Derivative Instruments, Gain (Loss) [Line Items]    
Gain (loss) to net income from derivative instruments 3.6 12.9
Designated as Hedging Instrument | Foreign exchange contracts | General, administrative and corporate expenses    
Derivative Instruments, Gain (Loss) [Line Items]    
Gain (loss) on foreign currency fair value hedge derivatives 0.7 (0.9)
Designated as Hedging Instrument | Foreign exchange contracts | Net change from current period hedged transactions    
Derivative Instruments, Gain (Loss) [Line Items]    
Gain (loss) on foreign currency fair value hedge derivatives $ 6.7 $ (6.5)