Pensions and Other Postretirement Benefits (Net Periodic Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pension and other postretirement benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7.8	$ 7.0	$ 23.5	$ 21.2
Interest cost	16.6	18.3	49.9	54.8
Expected return on plan assets	(16.9)	(16.4)	(50.7)	(49.2)
Amortization of prior service costs	0.5	0.1	1.6	0.1
Recognized net actuarial gains	(4.3)	(4.9)	(12.8)	(14.9)
Defined Benefit Plan, Other Cost (Credit)	0.0	(3.1)	0.0	1.3
Net periodic benefit cost	3.7	1.0	11.5	13.3
Defined Benefit Plan Items | Reclassification out of Accumulated Other Comprehensive Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service costs				$ (0.1)
Defined Benefit Plan Items | Reclassification out of Accumulated Other Comprehensive Income [Member] | Pension and other postretirement benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service costs	$ 0.5	$ 0.1	$ 1.6