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)
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-Article 12
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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.

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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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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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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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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.

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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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Derivative Instruments (Details) - USD ($) $ in Millions	3 Months Ended
Derivative Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	$ 552.6		$ 656.4
Changes in fiar value of non-designated derivatives	0.0	$ 0.0
Non-designated derivatives
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	175.6		158.7
Cash flow hedges \| Designated as hedge
Derivatives, Notional Amount [Line Items]
Notional amount of foreign currency derivatives	$ 377.0		$ 497.7
Maturities of cash flow hedge derivatives	18 months
Losses expected to be reclassified into earnings within the next 12 months	$ 2.8
Foreign exchange contracts \| Cash flow hedges
Derivatives, Notional Amount [Line Items]
Derivative instruments, gain (loss) recognized in other comprehensive income (loss), Effective portion	3.4	13.4
Cost of revenues and operating expenses \| Foreign exchange contracts \| Cash flow hedges
Derivatives, Notional Amount [Line Items]
Gain (loss) reclassified	$ (1.0)	$ 5.6