Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Income Statement (Detail) - Kronos - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Schedule Of Equity Method Investments [Line Items]
Net sales	$ 484.5	$ 471.8	$ 921.0	$ 902.2
Cost of sales	375.0	300.0	702.2	555.6
Income from operations	46.5	119.9	95.5	227.4
Income tax expense	11.4	32.4	24.2	61.4
Net income	$ 29.5	$ 77.7	$ 59.8	$ 148.4

Equity method investment summarized financial information income tax expense benefit.

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The amount of the cost of sales reported by an equity method investment of the entity.

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The amount of gross profit (loss) reported by an equity method investment of the entity.

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The amount of net income (loss) reported by an equity method investment of the entity.

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The amount of revenue from sale of goods and services reduced by sales returns, allowances, and discounts reported by an equity method investment of the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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