Divestitures and Held for Sale - Summary of Amounts Included in Discontinued Operations (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Discontinued Operations and Disposal Groups [Abstract]
Net sales	$ 455.8	$ 1,527.2	$ 996.7	$ 2,733.1
Cost of products sold	312.7	934.5	691.5	1,740.3
Selling, general and administrative expenses	65.8	260.0	142.5	514.1
Restructuring costs, net	1.3	2.5	1.3	5.0
Impairment of goodwill, intangibles and other assets	11.0	454.0	185.7	454.0
Operating income (loss)	65.0	(123.8)	(24.3)	19.7
Non-operating expense (income)	5.9	(461.4)	2.7	(461.0)
Income (loss) before income taxes	59.1	337.6	(27.0)	480.7
Income tax expense (benefit)	(52.3)	(129.5)	(45.6)	(164.6)
Net income (loss)	$ 6.8	$ 208.1	$ (72.6)	$ 316.1

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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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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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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