Pensions and Postretirement Benefits Other Than Pensions (Schedule of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net periodic benefit cost after net curtailment and settlement (gains) losses	$ (20.0)	$ (10.6)	$ (1.6)
Pension Plans [Member]
Service cost	34.4	47.5	50.9
Interest cost	119.6	70.3	58.6
Expected return on plan assets	(120.3)	(103.8)	(106.2)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	3.6	3.9	5.0
Plan net actuarial losses, net amortization of	16.2	23.3	35.6
Net periodic benefit cost	53.5	41.2	43.9
Net curtailment and settlement (gains) losses	1.4	15.0	8.0
Net periodic benefit cost after net curtailment and settlement (gains) losses	54.9	56.2	51.9
Segment, Discontinued Operations [Member] | Pension Plans [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	6.7	3.8	5.7
Other Nonoperating Income (Expense) [Member] | Segment, Continuing Operations [Member] | Pension Plans [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	18.6	9.2	(0.9)
Operating Income (Loss) [Member] | Segment, Continuing Operations [Member] | Pension Plans [Member]
Net periodic benefit cost after net curtailment and settlement (gains) losses	$ 29.6	$ 43.2	$ 47.1