Financial Instruments - Fair Value Measurements and Related Valuation Techniques and Fair Value Hierarchy Level (Detail) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Foreign exchange contract
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	$ 14.3	$ (22.8)
Fair value, measurements, recurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities	47.3	43.8
Fair value, measurements, recurring \| Foreign exchange contract
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	14.3	(22.8)
Fair value, measurements, recurring \| Interest rate swap contracts
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	(14.7)
Fair value, measurements, recurring \| Level 1
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities	47.3	43.8
Fair value, measurements, recurring \| Level 1 \| Foreign exchange contract
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	0.0	0.0
Fair value, measurements, recurring \| Level 1 \| Interest rate swap contracts
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	0.0
Fair value, measurements, recurring \| Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities	0.0	0.0
Fair value, measurements, recurring \| Level 2 \| Foreign exchange contract
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	14.3	(22.8)
Fair value, measurements, recurring \| Level 2 \| Interest rate swap contracts
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	(14.7)
Fair value, measurements, recurring \| Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Marketable equity securities	0.0	0.0
Fair value, measurements, recurring \| Level 3 \| Foreign exchange contract
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	0.0	$ 0.0
Fair value, measurements, recurring \| Level 3 \| Interest rate swap contracts
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Foreign currency contracts, net	$ 0.0

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

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+ References

No definition available.

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