Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Income Statement (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Schedule Of Equity Method Investments [Line Items]
Net sales	$ 37,971	$ 41,151
Cost of sales	28,304	28,447
Income (loss) from operations	1,356	4,197
Income tax expense	988	1,421
Net income (loss)	6,839	(6,716)
Kronos | Reportable Legal Entities
Schedule Of Equity Method Investments [Line Items]
Net sales	478,800	426,300
Cost of sales	407,300	395,500
Income (loss) from operations	19,500	(18,300)
Income tax expense	3,500	(6,900)
Net income (loss)	$ 8,100	$ (15,200)