v3.26.1
Fair Value (Available-For-Sale Securities) (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Fair Value Disclosure [Line Items]    
Amortized Cost $ 164.6 $ 145.8
Gross Unrealized Gains 1.4 2.4
Gross Unrealized Losses (2.7) (2.1)
Fair Value 163.3 146.1
U.S. Treasury debt securities    
Fair Value Disclosure [Line Items]    
Amortized Cost 10.4 9.5
Gross Unrealized Gains 0.0 0.0
Gross Unrealized Losses (0.1) 0.0
Fair Value 10.3 9.5
Corporate/Other debt securities    
Fair Value Disclosure [Line Items]    
Amortized Cost 154.2 136.3
Gross Unrealized Gains 1.4 2.4
Gross Unrealized Losses (2.6) (2.1)
Fair Value 153.0 136.6
Debt Securities, Available-for-sale, Unrealized Loss Position 74.2 40.2
US Treasury Securities    
Fair Value Disclosure [Line Items]    
Fair Value 5.8  
Debt Securities, Available-for-sale, Unrealized Loss Position $ 8.7 $ 3.5