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Derivative Instruments (Details 1) - Foreign Exchange Contract - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Cash flows, revenue | Revenue |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Amount Reclassified from Accumulated Other Comprehensive Income into Income Gain/(Loss) (Effective Portion) | $ (32.5) | $ 5.3 | $ 173.2
Cash flows, revenue | Other income (expense) |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in earnings of foreign currency forward contracts due to hedge ineffectiveness | 8.9 | 2.9 | 4.9
Cash flows, operating expenses | Other income (expense) |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in earnings of foreign currency forward contracts due to hedge ineffectiveness | (0.2) | 0.1 | 0.0
Cash flows, operating expenses | Operating Expense |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Amount Reclassified from Accumulated Other Comprehensive Income into Income Gain/(Loss) (Effective Portion) | $ 0.6 | $ (1.5) | $ 0.0

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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 + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + 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 (d) -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 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
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