v3.26.3
Pensions and Postretirement Benefits Other than Pensions (Components of Net Periodic Postretirement Benefit Cost) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Total $ (1.3) $ (4.2) $ (7.3) $ (13.3)
Postretirement Benefit Costs [Member]        
Service cost 0.3 0.3 0.7 0.8
Interest cost 2.3 2.7 7.0 8.2
Net amortization of prior service gains 0.1 0.1 0.4 0.4
Net amortization of plan net actuarial losses (2.6) (3.2) (7.7) (9.6)
Total 0.1 (0.1) 0.4 (0.2)
Postretirement Benefit Costs [Member] | Continuing Operations [Member]        
Total 0.2 0.3 0.7 0.8
Postretirement Benefit Costs [Member] | Discontinued Operations [Member]        
Total $ 0.0 $ (0.3) $ 0.0 $ (0.6)