Goodwill - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill [Line Items]
Goodwill	$ 379.7	$ 379.7	$ 379.7
Chemicals
Goodwill [Line Items]
Goodwill	352.6	352.6	352.6
Component Products [Member]
Goodwill [Line Items]
Goodwill	$ 27.1	$ 27.1	$ 27.1