Pensions and Postretirement Benefits Other Than Pensions (Schedule of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net periodic benefit cost after net curtailment and settlement (gains) losses	$ (39.3)	$ (21.9)	$ (31.0)
Pension Plan [Member]
Service cost	73.6	75.0	70.8
Interest cost	119.1	109.7	109.0
Expected return on plan assets	(138.5)	(146.6)	(141.7)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	5.0	4.2	3.8
Plan net actuarial losses, net amortization of	54.3	51.3	56.8
Net periodic benefit cost	113.5	93.6	98.7
Net curtailment and settlement (gains) losses	4.5	2.3	5.6
Net periodic benefit cost after net curtailment and settlement (gains) losses	118.0	95.9	104.3
Segment, Continuing Operations [Member] | Pension Plan [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	69.8	72.7	68.2
Segment, Discontinued Operations [Member] | Pension Plan [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	12.1	8.6	10.7
Other Nonoperating Income (Expense) [Member] | Segment, Continuing Operations [Member] | Pension Costs [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	$ 36.1	$ 14.6	$ 25.4