Profit Sharing, Retirement Savings Plans and Defined Benefit Pension Plans - Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 7.0	$ 10.6	$ 11.4
Interest cost	22.9	26.1	30.4
Expected return on plan assets	(40.4)	(34.3)	(39.7)
Other adjustments	0.0	1.3	0.0
Amortization of net prior service cost	(0.1)	0.0	0.0
Amortization of net loss	6.5	7.5	7.8
Net periodic benefit (income) cost	(4.1)	11.2	9.9
Cost (income) of settlement/curtailment	5.1	0.7	1.0
Total benefit cost	1.0	11.9	10.9
U.S.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.1	0.6	0.7
Interest cost	6.8	7.8	8.6
Expected return on plan assets	(9.8)	(10.0)	(11.4)
Other adjustments	0.0	1.3	0.0
Amortization of net prior service cost	0.0	0.0	0.0
Amortization of net loss	0.8	2.2	1.8
Net periodic benefit (income) cost	(2.1)	1.9	(0.3)
Cost (income) of settlement/curtailment	2.1	0.6	1.6
Total benefit cost	0.0	2.5	1.3
International
Defined Benefit Plan Disclosure [Line Items]
Service cost	6.9	10.0	10.7
Interest cost	16.1	18.3	21.8
Expected return on plan assets	(30.6)	(24.3)	(28.3)
Other adjustments	0.0	0.0	0.0
Amortization of net prior service cost	(0.1)	0.0	0.0
Amortization of net loss	5.7	5.3	6.0
Net periodic benefit (income) cost	(2.0)	9.3	10.2
Cost (income) of settlement/curtailment	3.0	0.1	(0.6)
Total benefit cost	$ 1.0	$ 9.4	$ 9.6