Hedging (Details) - USD ($)	6 Months Ended
Jun. 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	985,000	$ 15,593,000
Gross Amounts Offset	0	0
Gross Amounts Presented	985,000	15,593,000
Gross Amounts Not Offset	(985,000)	(144,000)
Legal Offset	0	15,449,000
Offsetting Derivative Liabilities [Abstract]
Gross Amounts Recognized	(9,502,000)	(144,000)
Gross Amounts Offset	0	0
Gross Amounts Presented	(9,502,000)	(144,000)
Gross Amounts Not Offset	985,000	144,000
Legal Offset	(8,517,000)	0
Prepaid and other current assets
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - assets	985,000	14,407,000
Other assets
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - assets	0	1,186,000
Other liabilities, current portion
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - liabilities	(8,067,000)	(144,000)
Other liabilities, excluding current portion
Foreign Currency Cash Flow Hedge Derivative at Fair Value [Abstract]
Fair Value - liabilities	(1,435,000)	0
Designated as hedging instrument \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	310,397,000	253,381,000
Designated as hedging instrument \| Euro \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	209,800,000	164,368,000
Designated as hedging instrument \| British pound sterling \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	71,917,000	65,237,000
Designated as hedging instrument \| Australian dollar \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Notional amount of foreign currency forward contract	$ 28,680,000	$ 23,776,000
Minimum \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Derivative term	1 month
Maximum \| Foreign currency forward contracts \| Cash flow hedging
Derivative [Line Items]
Derivative term	18 months

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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