Derivatives - Schedule of Pretax Effects of Derivative Financial Instruments Designated or Previously Designated as Effective Hedges (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	$ (8.7)	$ (15.4)
Gain/(Loss) Reclassified from AOCI to Income	(13.1)	(0.3)
Interest Rate Swaps [Member] \| Interest Expense, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Reclassified from AOCI to Income	(1.9)	(2.0)
Foreign Currency Contracts [Member] \| Sales and Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	(5.3)	(11.8)
Gain/(Loss) Reclassified from AOCI to Income	(6.4)	8.6
Cross-currency Swaps [Member] \| Other Income (Expense), Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (effective portion)	(3.4)	(3.6)
Gain/(Loss) Reclassified from AOCI to Income	$ (4.8)	$ (6.9)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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