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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 | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2019
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | $ 6.7 | $ 0.3
Gain Recognized in Earnings from Excluded Components | [1] | 3.5 | 7.0
Forward contracts |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | 26.6 | 9.8
Gain Recognized in Earnings from Excluded Components | [1] | 3.5 | 7.0
Put options |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | (12.3) | 5.6
Gain Recognized in Earnings from Excluded Components | [1] | 0.0 | 0.0
Call options |  |  |
Derivative [Line Items] |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  | (7.6) | (15.1)
Gain Recognized in Earnings from Excluded Components | [1] | 0.0 | 0.0
Foreign Currency Translation Adjustment |  |  |
Derivative [Line Items] |  |  |
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | 0.3 | 0.2
Foreign Currency Translation Adjustment | Forward contracts |  |  |
Derivative [Line Items] |  |  |
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | 0.3 | 0.2
Foreign Currency Translation Adjustment | Put options |  |  |
Derivative [Line Items] |  |  |
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | 0.0 | 0.0
Foreign Currency Translation Adjustment | Call options |  |  |
Derivative [Line Items] |  |  |
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  | $ 0.0 | $ 0.0
[1] | The excluded components of the forward contracts are recognized in earnings on a straight-line basis over the respective period of the contracts as a reduction to Interest expense on the Consolidated Statements of Income.

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- Definition Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Net of Tax + References No definition available. + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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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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