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Derivative Contracts - Narrative (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	May 09, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral provided	$ 0		$ 0
Goldman Sachs International
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount				$ 256,300,000
Foreign Exchange Contracts | Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	757,500,000		665,600,000
Foreign Exchange Contracts | Derivatives 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	3,100,000	$ (4,400,000)
Foreign Exchange Contracts | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Cash collateral provided	0		2,200,000
Foreign Exchange Contracts | Designated as Hedging Instrument | General and Administrative Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Foreign exchange contract settlement	300,000	(1,100,000)
Foreign Exchange Contracts | Designated as Hedging Instrument | Net change from current period hedged transactions [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Net unrealized gain (loss)	1,300,000	(2,100,000)
Foreign Exchange Contracts | Derivatives at Fair Value | Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	357,000,000		240,200,000
Foreign Exchange Contracts | Derivatives at Fair Value | Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	81,900,000		0
Net unrealized gain (loss)	700,000		2,200,000
Interest Rate Swaps | Derivatives 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	$ (2,800,000)
Interest Rate Swaps | Derivatives at Fair Value | Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	$ 0		$ 0

X

- Definition

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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- Definition

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
-Paragraph 4H
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624258-113959

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+ References

No definition available.

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
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-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 815
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