Property, Plant, and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant, and Equipment [Abstract]
Asset write-downs	$ 4.7	$ 0.0	$ 71.7
Depreciation and depletion expense	75.2	79.5	$ 79.4
Refractories Manufacturing Assets | China [Member]
Property, Plant, and Equipment [Abstract]
Gain on sale of assets, net	5.6	$ 12.3
Chromite Mine [Member] | South Africa [Member]
Property, Plant, and Equipment [Abstract]
Gain on sale of assets, net	$ 4.3