Other Income, Net - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Disclosure Other Income Net Additional Information Detail [Line Items]
Net proceeds				$ 23.4	$ 1.2
Pre-tax gain on sale of land	$ 10.4			16.0	0.5
Infrastructure reimbursement				6.2	19.6
Kronos Worldwide, Inc.
Disclosure Other Income Net Additional Information Detail [Line Items]
Gain on insurance settlement related to property damage claim			$ 1.5
BMI
Disclosure Other Income Net Additional Information Detail [Line Items]
Pre-tax gain on sale of land		$ 4.0
City Of Henderson
Disclosure Other Income Net Additional Information Detail [Line Items]
Infrastructure reimbursement				$ 6.2	$ 19.1