Business Combinations - Summary of Unaudited Pro Forma Financial Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2018	Sep. 30, 2018
Business Acquisition [Line Items]
Loss on foreign currency forward transactions	$ 29.0	$ 29.0
Hermes
Business Acquisition [Line Items]
Revenue		923.3
Net Income		$ 179.9

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.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of decrease in the fair value of derivatives recognized in the income statement.

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