v3.26.3
Pensions and Postretirement Benefits Other than Pensions (Components of the Company's Pension-Related Costs) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) $ (1.3) $ (4.2) $ (7.3) $ (13.3)
Pension Costs [Member]        
Service cost 6.2 7.4 17.7 22.2
Interest cost 23.2 28.1 69.4 83.7
Expected return on plan assets (25.6) (27.1) (76.7) (80.7)
Net amortization of prior service costs 0.4 0.7 1.2 2.1
Net amortization of plan net actuarial losses 3.2 4.1 9.7 12.0
Net periodic pension benefit cost 7.4 13.2 21.3 39.3
Net curtailment loss 0.0 0.0 (3.7) (0.7)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) 7.4 13.2 25.0 40.0
Pension Costs [Member] | Continuing Operations [Member]        
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) 5.3 6.4 15.3 18.9
Pension Costs [Member] | Discontinued Operations [Member]        
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) 0.7 2.5 2.1 7.4
Other Pension Plan | Continuing Operations [Member]        
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) $ 1.4 $ 4.3 $ 7.6 $ 13.7