v3.8.0.1

Financial Instruments and Fair Value Measurements - Schedule of Fair Value and Classification of Derivative Instruments (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Foreign Currency Options [Member] |  |  |  |
Derivatives Fair Value [Line Items] |  |  |  |
Unrealized gains (losses) on foreign exchange transactions | $ (12.3) | $ 3.1 | $ (44.8) | $ (10.4)

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- Definition Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated 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 (e) -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 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 + Details
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