Defined Benefit Pension Plans and Other Post-Employment Benefit Plans - Components of Net Periodic Benefit Cost (Income) for Defined Benefit Pension Plans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Components of net periodic benefit cost (income):
Service cost	$ 1.0	$ 1.2	$ 2.0	$ 2.2
Interest cost	5.5	5.5	10.9	11.0
Expected return on plan assets	(7.9)	(9.7)	(15.8)	(19.3)
Amortization of net prior service cost	0.1	0.0	0.1	0.0
Amortization of net actuarial loss	1.3	0.8	2.5	1.7
Net periodic cost (income)	0.0	(2.2)	(0.3)	(4.4)
Cost of settlement	0.1	0.1	0.3	0.1
Total benefit cost (income)	0.1	(2.1)	0.0	(4.3)
U.S.
Components of net periodic benefit cost (income):
Service cost	0.0	0.1	0.0	0.1
Interest cost	1.8	1.6	3.5	3.2
Expected return on plan assets	(1.8)	(2.2)	(3.6)	(4.4)
Amortization of net prior service cost	0.0	0.0	0.0	0.0
Amortization of net actuarial loss	0.4	0.2	0.7	0.5
Net periodic cost (income)	0.4	(0.3)	0.6	(0.6)
Cost of settlement	0.0	0.0	0.0	0.0
Total benefit cost (income)	0.4	(0.3)	0.6	(0.6)
International
Components of net periodic benefit cost (income):
Service cost	1.0	1.1	2.0	2.1
Interest cost	3.7	3.9	7.4	7.8
Expected return on plan assets	(6.1)	(7.5)	(12.2)	(14.9)
Amortization of net prior service cost	0.1	0.0	0.1	0.0
Amortization of net actuarial loss	0.9	0.6	1.8	1.2
Net periodic cost (income)	(0.4)	(1.9)	(0.9)	(3.8)
Cost of settlement	0.1	0.1	0.3	0.1
Total benefit cost (income)	$ (0.3)	$ (1.8)	$ (0.6)	$ (3.7)