Derivative Instruments, Cash Flow Hedges and Offsetting of Derivatives (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Derivatives, Fair Value [Line Items]
Maximum length of time hedged in cash flow hedge	1 year
Foreign exchange contract [Member] \| Cash flow hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative instruments, gain (loss) recognized in other comprehensive income (loss), Effective portion	$ (6.1)	$ 2.7
Foreign exchange contract [Member] \| Cash flow hedging [Member] \| Operating expense [Member]
Derivatives, Fair Value [Line Items]
Derivative instruments, gain (loss) reclassified from accumulated OCI into operating expense, Effective portion	$ 3.0	$ (1.0)

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4D

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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