Other Comprehensive Loss - Components of Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	$ (58.4)	$ (94.3)	$ (20.2)	$ (193.8)
Tax	0.0	0.0	0.2	(0.7)
Other comprehensive loss	(58.4)	(94.3)	(20.0)	(194.5)
Cumulative translation adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	(58.1)	(94.9)	(19.2)	(196.3)
Tax	0.0	0.0	0.0	0.0
Other comprehensive loss	(58.1)	(94.9)	(19.2)	(196.3)
Pension and other postretirement adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Pre-tax	(0.3)	0.6	(1.0)	2.5
Tax	0.0	0.0	0.2	(0.7)
Other comprehensive loss	$ (0.3)	$ 0.6	$ (0.8)	$ 1.8