Pensions and Other Benefit Programs (Schedule of Periodic Benefit Costs (Credits) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
U.S. Defined-Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned during the period	$ 1.2	$ 1.4	$ 3.6	$ 4.2
Interest cost on projected benefit obligation	2.2	2.8	6.7	12.7
Expected return on plan assets	(4.1)	(6.6)	(12.4)	(28.0)
Amortization of net actuarial (gain) loss	0.9	0.8	2.7	5.5
Settlement				374.4
Special termination benefits		2.0		2.0
Net periodic postretirement (credit) cost	0.2	0.4	0.6	370.8
Retiree Health And Life Insurance Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost on projected benefit obligation	0.3	0.4	0.9	1.4
Amortization of prior service credit	(0.1)	(0.1)	(0.2)	(0.2)
Amortization of net actuarial (gain) loss	(0.6)	(1.7)	(1.7)	(5.0)
Net periodic postretirement (credit) cost	$ (0.4)	$ (1.4)	$ (1.0)	$ (3.8)