Pension and Other Benefit Programs (Schedule of Periodic Benefit Costs (Credits) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
U.S. Defined-Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned during the period	$ 1.5	$ 2.1	$ 2.9	$ 4.2
Interest cost on projected benefit obligation	11.6	12.4	23.1	24.9
Expected return on plan assets	(24.0)	(24.8)	(48.0)	(49.6)
Amortization of prior service (credit) cost		0.3		0.7
Amortization of net actuarial (gain) loss	5.0	4.3	10.0	8.5
Net periodic pension\postretirement (credit)	(5.9)	(5.7)	(12.0)	(11.3)
Retiree Health And Life Insurance Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost of benefits earned during the period	0.1	0.1	0.1	0.2
Interest cost on projected benefit obligation	0.7	0.8	1.3	1.5
Amortization of net actuarial (gain) loss	(1.4)	$ (0.9)	(2.8)	(1.8)
Net periodic pension\postretirement (credit)	$ (0.6)		$ (1.4)	$ (0.1)