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
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
U.S.
Net periodic benefit costs of defined benefit retirement plans
Service cost	$ 0.2	$ 0.3
Interest cost	0.1	0.1
Net amortization and deferral	0.2	0.1
Net periodic benefit cost (credit)	$ 0.5	$ 0.5
Defined Benefit Plan, Tax Status [Extensible List]	Non-qualified	Non-qualified	Non-qualified
European
Net periodic benefit costs of defined benefit retirement plans
Service cost	$ 0.2	$ 0.2
Interest cost	0.5	0.9
Expected return on plan assets	(0.9)	(1.7)
Net amortization and deferral	0.3	0.1
Net periodic benefit cost (credit)	$ 0.1	$ (0.5)