Other Income, Net - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019
Disclosure Other Income Net Additional Information Detail [Line Items]
Infrastructure reimbursement		$ 19.1	$ 9.1
Kronos Worldwide, Inc.
Disclosure Other Income Net Additional Information Detail [Line Items]
Gain on insurance settlement related to property damage claim	$ 1.5
City Of Henderson
Disclosure Other Income Net Additional Information Detail [Line Items]
Infrastructure reimbursement		$ 19.1	$ 8.8