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

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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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 30
-Section 50
-Paragraph 1
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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
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-Name Accounting Standards Codification
-Topic 815
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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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No definition available.

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- Definition

Maximum amount of time remaining before foreign currency exchange rate derivatives mature or expire, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Derivative Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	$ 750.9		$ 750.9		$ 629.4
Non-designated derivatives
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	141.4		141.4		108.3
Cash flow hedges \| Designated as hedge
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	609.5		$ 609.5		$ 521.1
Maturities of cash flow hedge derivatives			18 months
Losses expected to be reclassified into earnings within the next 12 months			$ 5.8
Foreign exchange contracts \| Cash flow hedges
Derivatives, Notional Amount [Line Items]
Derivative instruments, gain (loss) recognized in other comprehensive income (loss), Effective portion	(6.1)	$ 6.8	(8.6)	$ 17.6
Cost of revenues and operating expenses \| Foreign exchange contracts \| Cash flow hedges
Derivatives, Notional Amount [Line Items]
Gain (loss) reclassified	$ (3.1)	$ 0.0	$ 5.8	$ 0.0