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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Total			$ (21.7)	$ (24.2)
Pension Costs [Member]
Service cost	$ 17.1	$ 16.7	52.8	53.2
Interest cost	27.3	27.7	81.3	84.6
Expected return on plan assets	(35.6)	(36.0)	(106.0)	(108.2)
Net amortization of prior service costs	0.9	0.6	2.8	3.0
Net amortization of plan net actuarial losses	14.3	16.2	41.4	46.5
Net periodic pension benefit cost	24.0	25.2	72.3	79.1
Net curtailment loss	(1.3)	0.0	(3.6)	0.0
Total	25.3	25.2	75.9	79.1
Pension Costs [Member] | Segment, Continuing Operations [Member]
Total
Pension Costs [Member] | Discontinued Operations [Member]
Total	$ 2.6	$ 2.4	$ 7.4	$ 7.4