Fair Value Measurements and Financial Instruments - Additional Information (Detail) - Kronos Worldwide, Inc.	Mar. 31, 2019 USD ($)	Mar. 31, 2019 EUR (€)	Mar. 31, 2018 USD ($)
3.75% Senior Secured Notes due September 15, 2025 | Kronos International, Inc
Financial Instrument At Fair Value [Line Items]
Estimated market price of the notes		€ 954
Principal amount of debt instrument		€ 1,000
Currency Forward Contracts
Financial Instrument At Fair Value [Line Items]
Currency forward contracts outstanding | $	$ 0		$ 0