Accounts Payable and Accrued Liabilities - Schedule of Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Payable to affiliates:
Accrued litigation settlement	$ 11.8	$ 60.0
Operating lease liabilities	6.4
Employee benefits	34.3	37.5
Deferred income	11.3	28.3
Accrued sales discounts and rebates	26.0	29.7
Environmental remediation and related costs	4.5	6.5
Interest	1.2	5.2
Other	38.4	33.6
Total	274.1	339.0
Kronos Worldwide, Inc.
Accounts payable:
Accounts payable	113.2	103.2
CompX
Accounts payable:
Accounts payable	3.5	3.2
BMI and LandWell
Accounts payable:
Accounts payable	3.9	2.9
NL
Accounts payable:
Accounts payable	1.5	1.6
Other
Accounts payable:
Accounts payable	0.4	0.6
Contran | Income Taxes Payable
Payable to affiliates:
Payable to affiliates	4.4	10.0
LPC | Trade Accounts Payables
Payable to affiliates:
Payable to affiliates	$ 13.3	$ 16.7