Retirement and Other Postretirement Benefit Plans - Schedule of Net Periodic Benefit Costs of Defined Benefit Retirement Plans (Details) - Defined Benefit Retirement Plans - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
U.S.
Net periodic benefit costs of defined benefit retirement plans
Service cost	$ 0.3	$ 0.4	$ 0.6	$ 0.7
Interest cost	0.2	0.1	0.3	0.3
Settlement expense		0.1		0.1
Net amortization and deferral		0.1		0.2
Net periodic benefit (credit) cost	$ 0.5	$ 0.7	$ 0.9	$ 1.3
Defined Benefit Plan, Tax Status [Extensible List]	us-gaap:NonqualifiedPlanMember	us-gaap:NonqualifiedPlanMember	us-gaap:NonqualifiedPlanMember	us-gaap:NonqualifiedPlanMember	us-gaap:NonqualifiedPlanMember
European
Net periodic benefit costs of defined benefit retirement plans
Service cost	$ 0.2	$ 0.2	$ 0.5	$ 0.4
Interest cost	1.1	1.1	2.2	2.2
Expected return on plan assets	(2.3)	(2.1)	(4.7)	(4.1)
Net amortization and deferral	0.1	0.1	0.2	0.2
Net periodic benefit (credit) cost	$ (0.9)	$ (0.7)	$ (1.8)	$ (1.3)