Income Taxes - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
	Mar. 27, 2020	Mar. 31, 2020	Dec. 31, 2017	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax [Line Items]
Deferred tax assets valuation allowance				$ 3.8	$ 7.4
Transition tax			$ 74.5
Noncurrent payable to affiliate				$ 33.5	44.7
Income tax liability payable period				8 years
Due To Affiliate Noncurrent				$ 33.5	44.7
Current payable to affiliate				22.9	18.2
Current cash tax benefit				(20.1)	(21.6)	$ (14.9)
Non-cash deferred income tax benefit				(1.6)	(11.0)	1.0
Business interest income, adjusted taxable income	30.00%
CARES act of 2020, Business interest income, adjusted taxable income	50.00%
Cash tax benefit due to reversal of valuation allowance		$ 0.5
Increase decrease in valuation allowance					$ 2.8	$ 2.8
Non-cash income tax benefit as a reduction of valuation allowance				3.5
Estimated unrecognized tax benefits decrease amount for next twelve months				1.0
Unrecognized tax benefits that would impact effective tax rate				3.2
Valhi | Income Tax Payable
Income Tax [Line Items]
Noncurrent payable to affiliate				33.5
Payable to affiliate				44.7
Due To Affiliate Noncurrent				33.5
Current payable to affiliate				11.2
Corporate Purposes
Income Tax [Line Items]
Deferred tax assets valuation allowance				0.0
D E | Corporate Purposes
Income Tax [Line Items]
Net operating loss carryforwards				414.0
B E | Corporate Purposes
Income Tax [Line Items]
Net operating loss carryforwards				$ 13.0