Divestitures and Held for Sale - Summary of Amounts Included in Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Discontinued Operations and Disposal Groups [Abstract]
Net sales	$ 147.5	$ 587.8	$ 684.9	$ 2,821.6
Cost of products sold	99.7	379.7	486.2	1,780.5
Selling, general and administrative expenses	26.5	126.6	111.5	577.9
Restructuring costs, net	0.0	1.8	0.5	6.2
Impairment of goodwill, intangibles and other assets	236.9	628.8	422.6	1,082.8
Operating loss	(215.6)	(549.1)	(335.9)	(625.8)
Non-operating expense (income)	(1.9)	(27.6)	0.6	(488.5)
Loss before income taxes	(213.7)	(521.5)	(336.5)	(137.3)
Income tax expense (benefit)	41.8	(64.2)	19.0	(243.9)
Net loss	$ (171.9)	$ (585.7)	$ (317.5)	$ (381.2)	$ (289.5)

Disposal group including discontinued operation impairment of goodwill, intangibles and other assets.

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Disposal group, including discontinued operation, nonoperating income (expense)

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Disposal group including discontinued operation restructuring costs.

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Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal.

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Amount of tax expense (benefit) attributable to income (loss) from operations classified as a discontinued operation. Excludes tax expense (benefit) for gain (loss) on disposal and for provision for gain (loss) until disposal.

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