Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Income Statement (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Schedule Of Equity Method Investments [Line Items]
Net sales	$ 42,050	$ 35,924
Cost of sales	29,970	24,889
Income from operations	3,870	3,972
Income tax expense	2,705	2,505
Net income	18,557	13,257
Kronos
Schedule Of Equity Method Investments [Line Items]
Net sales	562,900	465,000
Cost of sales	413,600	369,300
Income from operations	83,300	34,000
Income tax expense	18,300	6,000
Net income	$ 57,500	$ 19,600