Retirement and Other Postretirement Benefit Plans - Schedule of Net Periodic Cost of Defined Benefit Retirement and Postretirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net periodic benefit costs of defined benefit retirement plans
Net periodic pension cost (income)	$ 0.1	$ (1.0)	$ (1.6)
Defined Benefit Retirement Plans | U.S. Plans
Net periodic benefit costs of defined benefit retirement plans
Service cost	1.2	1.2	1.2
Interest cost	0.5	0.6	0.6
Net amortization	0.3	0.1	0.2
Net periodic pension cost (income)	2.0	1.9	2.0
Defined Benefit Retirement Plans | European Plans
Net periodic benefit costs of defined benefit retirement plans
Service cost	1.1	1.0	1.1
Interest cost	3.5	4.5	4.4
Expected return on plan assets	(6.9)	(8.7)	(9.4)
Net amortization	0.4	0.3	0.3
Net periodic pension cost (income)	(1.9)	(2.9)	(3.6)
U.S. Postretirement Plans
Net periodic benefit costs of defined benefit retirement plans
Interest cost	0.1	0.1	0.1
Net amortization	(1.0)	(1.1)	(1.0)
Net periodic pension cost (income)	$ (0.9)	$ (1.0)	$ (0.9)