Retirement Benefits - Components of Net Periodic Benefit Cost for Defined Benefit Plans and Other Postretirement Plans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 0.1	$ 0.1	$ 0.3	$ 0.3
Interest cost	0.2	0.1	0.3	0.2
Net amortization	(0.1)	(0.1)	(0.2)	(0.3)
Net periodic (benefit) cost	0.2	0.1	0.4	0.2
U.S. | Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.1	0.1	0.1	0.1
Interest cost	0.0	0.1	0.1	0.2
Expected return on plan assets	0.0	(0.6)	(0.1)	(0.8)
Settlement loss recognized	0.0	10.5	0.0	10.5
Net amortization	0.0	0.1	0.1	0.2
Net periodic (benefit) cost	0.1	10.2	0.2	10.2
Non-U.S. | Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	0.4	0.5	0.9	1.0
Interest cost	0.3	0.2	0.5	0.4
Expected return on plan assets	(0.3)	(0.3)	(0.6)	(0.5)
Settlement loss recognized	0.0	0.0	0.0	0.0
Net amortization	0.2	0.6	0.4	1.1
Net periodic (benefit) cost	$ 0.6	$ 1.0	$ 1.2	$ 2.0