Defined Benefit Pension Plans and Other Post-Employment Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Components of net periodic benefit cost or (income):
Service cost	$ 2.1	$ 2.6	$ 6.1	$ 7.8
Interest cost	7.4	8.4	21.5	25.1
Expected return on plan assets	(13.0)	(11.6)	(38.2)	(34.7)
Amortization of net prior service cost	(0.1)	0.1	(0.2)	0.2
Amortization of net actuarial loss	2.8	3.0	8.4	8.4
Net periodic benefit (income) cost	(0.8)	2.5	(2.4)	6.8
Cost (income) of settlement/curtailment	1.3	0.3	2.6	0.1
Total benefit (income) cost	0.5	2.8	0.2	6.9
U.S.
Components of net periodic benefit cost or (income):
Service cost	0.0	0.2	0.1	0.4
Interest cost	1.6	2.0	5.1	5.8
Expected return on plan assets	(2.4)	(2.5)	(7.3)	(7.5)
Amortization of net prior service cost	0.0	0.0	0.0	0.0
Amortization of net actuarial loss	0.2	0.7	0.6	1.7
Net periodic benefit (income) cost	(0.6)	0.4	(1.5)	0.4
Cost (income) of settlement/curtailment	0.4	0.0	1.2	0.0
Total benefit (income) cost	(0.2)	0.4	(0.3)	0.4
International
Components of net periodic benefit cost or (income):
Service cost	2.1	2.4	6.0	7.4
Interest cost	5.8	6.4	16.4	19.3
Expected return on plan assets	(10.6)	(9.1)	(30.9)	(27.2)
Amortization of net prior service cost	(0.1)	0.1	(0.2)	0.2
Amortization of net actuarial loss	2.6	2.3	7.8	6.7
Net periodic benefit (income) cost	(0.2)	2.1	(0.9)	6.4
Cost (income) of settlement/curtailment	0.9	0.3	1.4	0.1
Total benefit (income) cost	0.7	2.4	0.5	6.5
Other employee benefit plans
Components of net periodic benefit cost or (income):
Service cost	0.0	0.1	0.1	0.2
Interest cost	0.4	0.5	1.3	1.4
Amortization of net prior service cost	(0.3)	(0.5)	(1.1)	(1.2)
Amortization of net actuarial loss	0.0	0.0	(0.1)	0.0
Net periodic benefit (income) cost	0.1	0.1	0.2	0.4
Cost (income) of settlement/curtailment	(13.5)	0.0	(13.5)	0.0
Total benefit (income) cost	$ (13.4)	$ 0.1	$ (13.3)	$ 0.4