v3.26.1
Pension and Postretirement Benefit Plans (Net Pension And Postretirement Cost) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Pension benefits        
Defined Benefit Plan Disclosure [Line Items]        
Service cost $ 1.5 $ 1.9 $ 3.0 $ 3.7
Interest cost 6.6 6.7 13.2 13.3
Expected return on plan assets (7.4) (6.5) (14.9) (12.8)
Amortization of net actuarial losses 2.2 2.3 4.5 4.4
Amortization of prior service cost 0.4 0.4 0.8 0.8
Net periodic cost 3.3 4.8 6.6 9.4
Postretirement benefits        
Defined Benefit Plan Disclosure [Line Items]        
Service cost 0.1 0.0 0.1 0.0
Interest cost 0.5 0.3 0.9 0.7
Amortization of net actuarial losses 0.0 (0.1) 0.0 (0.1)
Amortization of prior service cost 0.1 0.1 0.2 0.2
Net periodic cost $ 0.7 $ 0.3 $ 1.2 $ 0.8