Post Employment Plans - Projected Benefit Obligation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Settlements	$ 0.0
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning	162.5
Settlements	0.0
Fair value of plan assets at end of period	151.9	$ 162.5
Pension plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation, beginning	174.0	158.9
Curtailment	(1.2)	(1.0)
Service costs	3.0	4.5	$ 4.1
Interest cost	3.8	3.3	3.6
Actuarial gain	(1.6)	(10.3)
Contributions paid	0.3	0.1
Benefits paid	(1.6)	(2.5)
Settlements	(0.5)	0.0
Foreign currency translation	(7.6)	21.0
Projected benefit obligation, ending	168.6	174.0	158.9
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning	162.5	138.2
Actual return on plan assets	(3.1)	5.5
Benefits paid	(1.6)	(2.5)
Settlements	(0.5)	0.0
Employer contributions	1.2	2.2
Contributions paid	0.3	0.1
Foreign currency translation	(6.9)	19.0
Fair value of plan assets at end of period	151.9	162.5	138.2
Funded (unfunded) status	(16.7)	(11.5)
Presented as:
Other non-current assets	15.7	22.0
Other non-current liabilities	(32.4)	(33.5)
Other Postretirement Benefits Plan
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Projected benefit obligation, beginning	6.2	5.8
Curtailment	0.0	0.0
Service costs	0.6	0.6	0.6
Interest cost	0.2	0.2	0.2
Actuarial gain	(1.3)	(0.3)
Contributions paid	0.0	0.0
Benefits paid	(0.1)	(0.1)
Settlements		0.0
Foreign currency translation	0.0	0.0
Projected benefit obligation, ending	5.6	6.2	5.8
Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning	0.0	0.0
Actual return on plan assets	0.0	0.0
Benefits paid	(0.1)	0.0
Settlements		0.0
Employer contributions	0.1	0.0
Contributions paid	0.0	0.0
Foreign currency translation	0.0	0.0
Fair value of plan assets at end of period	0.0	0.0	$ 0.0
Funded (unfunded) status	(5.6)	(6.2)
Presented as:
Other non-current assets	0.0	0.0
Other non-current liabilities	$ 0.0	$ 0.0