Hedging - Derivatives Designated as Hedging Instruments (Details) - USD ($)	9 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Amount of ineffectiveness on net investment hedges	$ 0
Foreign currency forward contracts
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized		$ 15,593,000
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized		(144,000)
Foreign currency forward contracts \| Designated as hedging instrument \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	343,147,000	253,381,000
Offsetting Derivative Assets [Abstract]
Gross Amounts Recognized	50,000	15,593,000
Gross Amounts Offset	0	0
Gross Amounts Presented	50,000	15,593,000
Gross Amounts Not Offset	(50,000)	(144,000)
Legal Offset	0	15,449,000
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(14,874,000)	(144,000)
Gross Amounts Offset	0	0
Gross Amounts Presented	(14,874,000)	(144,000)
Gross Amounts Not Offset	50,000	144,000
Legal Offset	(14,824,000)	0
Foreign currency forward contracts \| Designated as hedging instrument \| Euro \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	234,477,000	164,368,000
Foreign currency forward contracts \| Designated as hedging instrument \| British pound sterling \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	77,387,000	65,237,000
Foreign currency forward contracts \| Designated as hedging instrument \| Australian dollar \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	$ 31,283,000	23,776,000
Foreign currency forward contracts \| Minimum \| Cash flow hedging
Derivative [Line Items]
Derivative term	1 month
Foreign currency forward contracts \| Maximum \| Cash flow hedging
Derivative [Line Items]
Derivative term	18 months
Prepaid and other current assets
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - assets	$ 42,000	14,407,000
Other assets
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - assets	8,000	1,186,000
Other liabilities, current portion
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - liabilities	(13,897,000)	(144,000)
Other liabilities, excluding current portion
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - liabilities	$ (977,000)	$ 0

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
-Sentence Column B

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Gain (loss) on hedging derivative instrument or the foreign currency transaction gain (loss) on the nonderivative hedging instrument designated as a hedge of a net investment in foreign operations related to hedge ineffectiveness, which is included in earnings in the period.

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