Investment in TiO2 Manufacturing Joint Venture and Other Assets - Components of Net Distributions from LPC (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Summary Of Investment Holdings [Line Items]
Net distributions (contributions)	$ 4.0	$ (6.0)	$ 3.6
LPC
Summary Of Investment Holdings [Line Items]
Distributions from LPC	34.3	44.0	35.0
Contributions to LPC	$ (30.3)	$ (50.0)	$ (31.4)

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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