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

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Derivative Instruments (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Gain/Loss on fair value of foreign currency forward contracts	$ (0.5)	$ 27.3	$ (113.0)
Range of durations of foreign currency forward contracts	15 months
Net gains (losses) of other income (expense) related to foreign currency forward contracts	$ 5.9	2.0	$ 4.5
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	1,892.4	2,239.1
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 793.8	$ 735.1
Interest rate swap \| Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative, 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	15 months	12 months
Short-term derivative
Derivatives, Fair Value [Line Items]
Gain/Loss on fair value of foreign currency forward contracts	$ 2.4
Range of durations of foreign currency forward contracts	12 months