Income Statement Impacts Related to Derivatives Not Designated as Hedging Instruments (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Not Designated as Hedging Instrument \| Foreign Exchange Contracts \| Other Income And Expense [Member]
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Amount of Gain (Loss) Recorded in Income on Derivative	$ (2.2)	$ 1.1	$ 14.9	$ 29.7
Fair Value Hedging [Member]
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Derivative, Loss on Derivative	$ 0.8	$ 0.8	$ 1.6	$ 1.6

Derivative Instruments and Hedging Activities Disclosure [Line Items]

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- Definition

Amount of decrease in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

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