Pensions and Postretirement Benefits Other than Pensions (Components of the Company's Pension-Related Costs) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Total	$ (1.7)	$ (9.8)
Pension Costs [Member]
Service cost	17.7	18.1
Interest cost	22.5	29.8
Expected return on plan assets	(31.9)	(34.6)
Net amortization of prior service costs	1.3	1.2
Net amortization of plan net actuarial losses	11.3	13.4
Net periodic pension benefit cost	20.9	27.9
Net curtailment loss	3.6	(1.6)
Total	17.3	29.5
Pension Costs [Member] | Continuing Operations [Member]
Total
Pension Costs [Member] | Discontinued Operations [Member]
Total	1.8	6.9
Operating Income (Loss) [Member] | Pension Costs [Member] | Continuing Operations [Member]
Total	14.8	14.3
Other Nonoperating Income (Expense) [Member] | Pension Costs [Member] | Continuing Operations [Member]
Total	$ 0.7	$ 8.3