Long-Term Debt - Revolving Credit Facility - Additional Information (Detail) - Kronos Worldwide, Inc. € in Millions, $ in Millions	1 Months Ended	3 Months Ended
	Jan. 31, 2017	Mar. 31, 2017 USD ($)	Mar. 31, 2017 EUR (€)
Foreign Line of Credit | Europe
Line Of Credit Facility [Line Items]
Amount available for borrowing		$ 88.3	€ 82.7
Percentage of borrowings available under credit facility		69.00%	69.00%
Line of credit, maturity date		Sep. 30, 2017
North American Revolving Credit Facility
Line Of Credit Facility [Line Items]
Line of credit maturity, description		In January 2017, Kronos extended the maturity date of its North American revolving credit facility to the earlier of (i) January 30, 2022 or (ii) 90 days prior to the maturity date of our existing term loan indebtedness (or 90 days prior to the maturity date of any indebtedness incurred in a permitted refinancing of such existing term loan indebtedness). Based on the February 2020 maturity date of our existing term loan, the maturity date of the North American revolving credit facility is currently November 2019.
Revolving credit facility, borrowings		$ 26.0
Debt instrument, Interest rate at period end		4.75%	4.75%
Debt instrument, average interest rate during period		4.72%
Amount available for borrowing		$ 74.9
North American Revolving Credit Facility | Maturity Date Option 1
Line Of Credit Facility [Line Items]
Line of credit, maturity date		Jan. 30, 2022
North American Revolving Credit Facility | Maturity Date Option 2
Line Of Credit Facility [Line Items]
Line of credit, maturity date		Nov. 30, 2019
Maturity date of term loan	90 days
Maturity date permitted refinancing of term loan	90 days