Location and Fair Value of Derivative Instruments Designated as Hedging Instruments (Detail) - Derivatives Designated as Hedging Instruments - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	$ 11.0	$ 14.8
Fair value of derivative liability	1.3	6.2
Forward currency contracts \| Other Current Assets
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	9.4	10.9
Forward currency contracts \| Other Assets
Derivatives, Fair Value [Line Items]
Fair value of derivative assets	1.6	3.9
Forward currency contracts \| Accrued Expenses
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	1.1	6.2
Forward currency contracts \| Other Long-term Liabilities
Derivatives, Fair Value [Line Items]
Fair value of derivative liability	$ 0.2	$ 0.0

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=82924980&loc=SL51823488-111719

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226000-175313

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