Goodwill and Other Intangible Assets, Net - Schedule of Other Intangible Assets and Related Amortization Periods (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Mar. 31, 2019
Intangible Assets [Line Items]
Indefinite life, Net Book Value	$ 4,093.1
Gross Carrying Amount	6,298.6	6,301.6
Accumulated Amortization	(719.0)	(765.2)
Net Book Value	5,579.6	5,536.4
Trade Names [Member]
Intangible Assets [Line Items]
Indefinite life, Net Book Value	4,093.0	4,089.4
Trade Names [Member]
Intangible Assets [Line Items]
Indefinite life, Net Book Value	4,093.0	4,089.4
Gross Carrying Amount	170.5	170.3
Accumulated Amortization	(36.5)	(39.9)
Net Book Value	$ 134.0	130.4
Trade Names [Member] \| Minimum [Member]
Intangible Assets [Line Items]
Amortization periods	2 years
Trade Names [Member] \| Maximum [Member]
Intangible Assets [Line Items]
Amortization periods	15 years
Capitalized Software [Member]
Intangible Assets [Line Items]
Gross Carrying Amount	$ 520.0	529.0
Accumulated Amortization	(348.1)	(363.7)
Net Book Value	$ 171.9	165.3
Capitalized Software [Member] \| Minimum [Member]
Intangible Assets [Line Items]
Amortization periods	3 years
Capitalized Software [Member] \| Maximum [Member]
Intangible Assets [Line Items]
Amortization periods	12 years
Patents and Intellectual Property [Member]
Intangible Assets [Line Items]
Gross Carrying Amount	$ 136.4	134.1
Accumulated Amortization	(79.2)	(83.4)
Net Book Value	$ 57.2	50.7
Patents and Intellectual Property [Member] \| Minimum [Member]
Intangible Assets [Line Items]
Amortization periods	3 years
Patents and Intellectual Property [Member] \| Maximum [Member]
Intangible Assets [Line Items]
Amortization periods	14 years
Customer Relationships & Distributor Channels [Member]
Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,269.7	1,269.8
Accumulated Amortization	(180.9)	(196.9)
Net Book Value	$ 1,088.8	1,072.9
Customer Relationships & Distributor Channels [Member] \| Minimum [Member]
Intangible Assets [Line Items]
Amortization periods	3 years
Customer Relationships & Distributor Channels [Member] \| Maximum [Member]
Intangible Assets [Line Items]
Amortization periods	30 years
Other [Member]
Intangible Assets [Line Items]
Gross Carrying Amount	$ 109.0	109.0
Accumulated Amortization	(74.3)	(81.3)
Net Book Value	$ 34.7	$ 27.7
Other [Member] \| Minimum [Member]
Intangible Assets [Line Items]
Amortization periods	3 years
Other [Member] \| Maximum [Member]
Intangible Assets [Line Items]
Amortization periods	5 years

Intangible Assets [Line Items]

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
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