Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Balance at the beginning of the year	$ 242,374
Equity in earnings of Kronos Worldwide, Inc.	34,323	$ 19,437	$ 26,470
Dividends received from Kronos	(25,356)	(25,356)	(25,356)
Equity in Kronos' other comprehensive income (loss):
Balance at the end of the year	264,803	242,374
Defined Benefit Pension Plans
Equity in Kronos' other comprehensive income (loss):
Defined benefit pension plans/ Other postretirement benefit plans	56	478	2,914
Kronos
Balance at the beginning of the year	242,400	248,400	255,500
Equity in earnings of Kronos Worldwide, Inc.	34,300	19,400	26,500
Dividends received from Kronos	(25,400)	(25,400)	(25,400)
Equity in Kronos' other comprehensive income (loss):
Currency translation	(2,100)	4,100	(500)
Other		(300)	(900)
Balance at the end of the year	264,800	242,400	248,400
Kronos | Defined Benefit Pension Plans
Equity in Kronos' other comprehensive income (loss):
Defined benefit pension plans/ Other postretirement benefit plans	$ 15,600	(3,700)	(6,700)
Kronos | OPEB
Equity in Kronos' other comprehensive income (loss):
Defined benefit pension plans/ Other postretirement benefit plans		$ (100)	$ (100)