Business Combinations, Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Beginning balance	$ 57.7	$ 57.7
Warrick impairment	0.0	(20.5)
Ending balance	57.7	37.2
Accumulated impairment loss	(38.9)	(18.4)
Net carrying value	$ 18.8	$ 18.8