Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Schedule Of Equity Method Investments [Line Items]
Balance at the beginning of the period			$ 292,206
Equity in loss of Kronos	$ (6,229)	$ 6,416	(13,382)	$ 37,940
Dividends received from Kronos			(20,075)	$ (20,074)
Equity in Kronos' other comprehensive income (loss):
Balance at the end of the period	255,233		255,233
Kronos
Schedule Of Equity Method Investments [Line Items]
Balance at the beginning of the period			292,200
Equity in loss of Kronos			(13,400)
Dividends received from Kronos			(20,100)
Equity in Kronos' other comprehensive income (loss):
Currency translation			(4,300)
Defined benefit pension plans			700
Other			100
Balance at the end of the period	$ 255,200		$ 255,200