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)
-Number 210
-Article 12
-Section 13
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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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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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Derivative Contracts - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016	May 09, 2016
Goldman Sachs International
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount						$ 256.3
Foreign Exchange Contracts \| Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral provided	$ 0.6		$ 0.6		$ 0.0
Derivative notional amount	760.2		760.2		665.6
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	4.5	$ 0.6	25.2	$ (3.7)
Foreign Exchange Contracts \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral provided	0.0		0.0		2.2
Foreign Exchange Contracts \| Designated as Hedging Instrument \| General and Administrative Expense
Derivative Instruments, Gain (Loss) [Line Items]
Foreign exchange contract settlement	1.2	(3.1)	2.4	(5.6)
Foreign Exchange Contracts \| Designated as Hedging Instrument \| Net change from current period hedged transactions
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gain (loss)	(0.4)	3.1	3.3	(1.9)
Foreign Exchange Contracts \| Derivatives at Fair Value \| Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	521.5		521.5		240.2
Foreign Exchange Contracts \| Derivatives at Fair Value \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	27.3		27.3		0.0
Foreign Exchange Contracts \| Liabilities under Derivative Contracts \| Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	0.0		0.0		$ 108.6
Interest Rate Swaps \| 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	$ 0.0	$ 0.0	$ 0.0	$ (3.3)