Pension Plans and Other Benefits - Changes in Net Periodic Pension Cost (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income
The estimated net actuarial (gain) loss and prior service cost (credit) for the pension plans that will be amortized from accumulated other comprehensive income into net periodic benefit cost in the next fiscal year	$ 11.5
North American Pension Plans
Net Periodic Benefit Cost Before Settlements:
Service cost	4.8	$ 6.2	$ 5.9
Interest cost	25.0	24.0	24.3
Expected return on plan assets	(33.8)	(39.7)	(41.3)
Prior service cost	2.3	2.4	2.3
Actuarial loss	9.2	9.1	2.8
Preliminary net periodic benefit cost (income)	7.5	2.0	(6.0)
Curtailment/settlement expense	0.0	1.2	2.4
Total net periodic benefit cost (income)	7.5	3.2	(3.6)
Other Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income
Prior service (credit) cost recognized in other comprehensive income	5.5	(4.3)	(3.8)
Net actuarial loss (gain) recognized in other comprehensive income	(13.9)	5.0	(4.0)
Total recognized in other comprehensive income (loss)	(8.4)	0.7	(7.8)
Total recognized in net periodic benefit (income) cost and other comprehensive income	$ (0.9)	$ 3.9	$ (11.4)