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

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

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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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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.

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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.

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Derivative Instruments (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Gain/Loss on fair value of foreign currency forward contracts	$ (27.3)	$ 113.0	$ (49.8)
Range of durations of foreign currency forward contracts	12 months
Net gains (losses) of other income (expense) related to foreign currency forward contracts	$ 2.0	4.5	$ 29.2
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Aggregate notional amount	2,239.1	2,198.7
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Aggregate notional amount	$ 735.1	$ 564.9
Interest rate swap \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Aggregate notional amount				$ 675.0
2.90% Senior Notes due 2020
Derivatives, Fair Value [Line Items]
Interest rate on senior notes	2.90%			2.90%
Minimum
Derivatives, Fair Value [Line Items]
Range of durations of foreign currency forward contracts	1 month	1 month
Maximum
Derivatives, Fair Value [Line Items]
Range of durations of foreign currency forward contracts	12 months	21 months
Accrued expenses and other \| Foreign Exchange Contract \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability derivatives	$ 6.9	$ 84.7
Accrued expenses and other \| Foreign Exchange Contract \| Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability derivatives	$ 3.2	$ 3.0