Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Balance at the beginning of the period	$ 264,803
Equity in earnings of Kronos Worldwide, Inc.	17,533	$ 5,968
Dividends received from Kronos	(6,692)	$ (6,339)
Balance at the end of the year	278,892
Kronos
Balance at the beginning of the period	264,800
Equity in earnings of Kronos Worldwide, Inc.	17,500
Dividends received from Kronos	(6,700)
Currency translation	2,000
Other	600
Balance at the end of the year	278,900
Kronos \| Defined Benefit Pension Plans
Defined benefit pension plans	$ 700

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