Derivative Instruments.

No definition available.

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- Definition

Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

+ References

No definition available.

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Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Contractual interest rate for funds borrowed, under the debt agreement.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
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No definition available.

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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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.

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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.

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- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

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+ References

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Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Derivative Instruments (Textual) [Abstract]
Range of durations of foreign currency forward contracts			12 months
Gain/Loss on fair value of foreign currency forward contracts	$ 3.3		$ 3.3		$ (113.0)
Net gains (losses) of other income (expense) related to foreign currency forward contracts	(5.2)	$ 1.2	$ (4.8)	$ 5.7
Minimum
Derivative Instruments (Textual) [Abstract]
Range of durations of foreign currency forward contracts			1 month		1 month
Maximum
Derivative Instruments (Textual) [Abstract]
Range of durations of foreign currency forward contracts			15 months		21 months
Not designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	691.7		$ 691.7		$ 564.9
Other current assets \| Designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative asset, fair value, net	25.6		25.6		0.7
Other current assets \| Not designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative asset, fair value, net	4.1		4.1		1.8
Investments and other assets \| Designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative asset, fair value, net	5.4		5.4		0.2
Accrued expenses and other \| Designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative liability, fair value, net	10.9		10.9		84.7
Accrued expenses and other \| Not designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative liability, fair value, net	1.6		1.6		3.0
Other long-term liabilities \| Designated as hedging instrument
Summary of Derivatives designated as Hedging Instruments
Derivative liability, fair value, net	18.7		18.7		23.6
Foreign exchange contract \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	1,733.7		1,733.7		2,198.7
Interest rate swap \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	675.0		675.0
Revenue \| Cash flows, revenue \| Foreign exchange contract
Derivative Instruments (Textual) [Abstract]
Net gains (losses) in operating income for the settlement of certain effective cash flow hedge instruments	(8.4)	(18.8)	(51.7)	(15.1)
Net gains (losses) in net income of foreign currency forward contracts due to exclusion from effectiveness testing	0.3		7.3
Operating expense \| Cash flows, operating expenses \| Foreign exchange contract
Derivative Instruments (Textual) [Abstract]
Net gains (losses) in operating income for the settlement of certain effective cash flow hedge instruments	(0.3)	0.5	0.6	0.7
Net gains (losses) in net income of foreign currency forward contracts due to exclusion from effectiveness testing	0.4		0.0
Other income (expense) \| Cash flows, revenue \| Foreign exchange contract
Derivative Instruments (Textual) [Abstract]
Net gains (losses) in net income of foreign currency forward contracts due to exclusion from effectiveness testing		0.7		6.7
Other income (expense) \| Cash flows, operating expenses \| Foreign exchange contract
Derivative Instruments (Textual) [Abstract]
Net gains (losses) in net income of foreign currency forward contracts due to exclusion from effectiveness testing		$ 0.2		$ (0.1)
Euro \| Foreign exchange contract \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	1,662.5		1,662.5		1,875.6
British pound \| Foreign exchange contract \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	34.9		34.9		150.9
Canadian dollar \| Foreign exchange contract \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	26.9		26.9		83.5
Swiss franc \| Foreign exchange contract \| Designated as hedging instrument
Derivative Instruments (Textual) [Abstract]
Aggregate notional amount	$ 9.4		$ 9.4		$ 88.7
2.900% Senior Notes due 2020
Derivative Instruments (Textual) [Abstract]
Senior Notes interest rate	2.90%		2.90%
Short-term derivative [Member]
Derivative Instruments (Textual) [Abstract]
Unrealized gain (loss) on foreign currency derivatives, net, before tax			$ 7.0