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Derivative Financial Instruments - Effect on Statement of Comprehensive Income and Statement of Income (Details) - Designated as Hedging Instrument - Derivatives in Net Investment Hedging Relationship - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2018
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | $ (4.0) | $ (3.7)
Interest Expense |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Earnings from Excluded Components | [1] | 0.5 | 0.5
Forward contracts |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | (5.9) | (5.6)
Forward contracts | Interest Expense |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Earnings from Excluded Components | [1] | 0.5 | 0.5
Put option |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | 1.6 | 1.6
Put option | Interest Expense |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Earnings from Excluded Components | [1] | 0.0 | 0.0
Call option |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | 0.3 | 0.3
Call option | Interest Expense |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Earnings from Excluded Components | [1] | $ 0.0 | $ 0.0
[1] | The excluded components are recorded as a reduction in Interest expense.

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- Definition 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. + References No definition available. + Details
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- Definition Amount, after tax, of reclassification from accumulated other comprehensive income (AOCI) of gain (loss) from increase (decrease) in fair value of net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CCC -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998896-113959 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669646-108580 + Details
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- Details
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