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Investment in Kronos Worldwide, Inc. - Additional Information (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
	Jul. 16, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Kronos | Louisiana Pigment Company
Schedule Of Equity Method Investments [Line Items]
Percentage of voting interests acquired	50.00%
Business Combination non-cash gain		$ 4.6
Equity interest in acquiree percentage	50.00%
Payments to acquire businesses gross	$ 185.0
Business combination contingent consideration liability	$ 15.0	$ 0.0
Non-cash gain before tax associated with remeasurement			$ 64.5
Estimated fair value of existing ownership			178.2
Aggregate carrying value			$ 113.7
Kronos
Schedule Of Equity Method Investments [Line Items]
Number of shares owned		35.2		35.2
Quoted market price per share		$ 5.74		$ 9.75
Aggregate market value		$ 202.2		$ 343.4

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