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Derivative Contracts - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Foreign Exchange Contracts | Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	$ 1,274.1		$ 1,257.3
Foreign Exchange Contracts | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	(3.1)	$ 23.5
Foreign Exchange Contracts | Designated as Hedging Instrument | General and Administrative Expense
Derivative Instruments, Gain (Loss) [Line Items]
Foreign exchange contract settlement	0.4	1.7
Foreign Exchange Contracts | Designated as Hedging Instrument | Net change from current period hedged transactions
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gain (loss)	1.7	0.9
Foreign Exchange Contracts | Derivatives at Fair Value | Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	667.6		496.5
Foreign Exchange Contracts | Derivatives at Fair Value | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	70.8		0.0
Foreign Exchange Contracts | Liabilities under Derivative Contracts | Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Liability notional amount	606.5		760.8
Foreign Exchange Contracts | Liabilities under Derivative Contracts | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	0.0		94.3
Interest Rate Swap | Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Initial and margin posted	109.1		0.0
Interest Rate Swap | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	(50.2)	$ 0.0
Interest Rate Swap | Liabilities under Derivative Contracts | Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Liability notional amount	$ 3,318.0		$ 0.0

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

+ References

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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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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-Publisher FASB
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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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Nominal or face amount used to calculate payments on the derivative liability.

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Amount of gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective.

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