Accumulated Other Comprehensive Loss - Summary of Changes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (490.3)	$ (533.3)	$ (385.1)
Net current period other comprehensive income	0.2	1.1	1.8
Ending balance	(711.9)	(490.3)	(533.3)
Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(7.2)	(8.3)	(10.1)
Other comprehensive income before reclassifications	0.2	1.1
Net current period other comprehensive income	0.2	1.1	1.8
Ending balance	(7.0)	(7.2)	(8.3)
Defined Benefit Pension and Retiree Health Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(7.2)	(8.3)
Other comprehensive income before reclassifications	0.2	1.1
Net current period other comprehensive income	0.2	1.1
Ending balance	$ (7.0)	$ (7.2)	$ (8.3)