Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Schedule Of Equity Method Investments [Line Items]
Balance at the beginning of the period			$ 247,582
Equity in earnings of Kronos	$ 21,982	$ (6,229)	30,431	$ (13,382)
Dividends received from Kronos			(15,144)	$ (20,075)
Equity in Kronos' other comprehensive income (loss):
Balance at the end of the period	259,556		259,556
Kronos
Schedule Of Equity Method Investments [Line Items]
Balance at the beginning of the period			247,600
Equity in earnings of Kronos			30,400
Dividends received from Kronos			(15,100)
Equity in Kronos' other comprehensive income (loss):
Currency translation			(3,700)
Balance at the end of the period	$ 259,600		259,600
Kronos | Defined Benefit Pension Plans
Equity in Kronos' other comprehensive income (loss):
Defined benefit pension plans			$ 400