Accounts Payable and Accrued Liabilities - Components of Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Accounts Payable And Accrued Liabilities [Line Items]
Accounts payable	$ 137.9	$ 143.6
Employee benefits	17.1	28.7
Accrued sales discounts and rebates	20.9	28.9
Operating lease liabilities	$ 3.5	$ 3.7
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total	Total
Other	$ 53.3	$ 52.0
Total	267.6	275.1
LPC
Accounts Payable And Accrued Liabilities [Line Items]
Payables to affiliate	22.6	17.3
Valhi | Income taxes
Accounts Payable And Accrued Liabilities [Line Items]
Payables to affiliate	$ 12.3	$ 0.9