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Derivative Contracts - Gain/(Loss) Recognized in Income on Derivative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Not Designated as Hedging Instrument | Interest Rate Swaps | Change In Fair Value Of Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to net income from derivative instruments	$ 0.0	$ (3.1)
Not Designated as Hedging Instrument | Foreign Exchange Contracts | Change In Fair Value Of Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) to net income from derivative instruments	27.7	(21.5)
Designated as Hedging Instrument | Foreign Exchange Contracts | General, administrative and corporate expenses
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on foreign currency fair value hedge derivatives	4.4	(8.7)
Designated as Hedging Instrument | Foreign Exchange Contracts | Net change from current period hedged transactions
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on foreign currency fair value hedge derivatives	$ 3.0	$ 0.7

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+ References

No definition available.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or 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 (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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Amount of gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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