Divestitures and Held for Sale - Summary of Amounts Included in Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Discontinued Operations and Disposal Groups [Abstract]
Net sales	$ 859.3	$ 1,197.0	$ 3,592.4	$ 3,901.1
Cost of products sold	552.8	794.2	2,293.1	2,490.1
Selling, general and administrative expenses	155.3	219.7	669.4	743.9
Restructuring costs, net	2.8	2.9	7.8	13.8
Impairment of goodwill, intangibles and other assets	628.8		1,082.8	0.7
Operating income (loss)	(480.4)	180.2	(460.7)	652.6
Non-operating expense (income)	(27.3)	(5.4)	(488.3)	(1.3)
Income before income taxes	(453.1)	185.6	27.6	653.9
Income tax expense (benefit)	(62.6)	62.3	227.2	230.0
Net income (loss)	$ (515.7)	$ 123.3	$ (199.6)	$ 423.9

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

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Disposal group, including discontinued operation, non operating 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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Amount of costs of goods sold attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of general and administrative expense attributable to disposal group, including, but not limited to, discontinued operation.

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