Derivative Instruments - Derivatives Not Designated as Hedging Instruments (Details) - Other expense - net - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments
Amount of Gain or (Loss) Recognized in Income on Derivatives Not Designated as Hedging Instruments	$ 4,425	$ (1,042)	$ (511)
Foreign exchange contracts
Derivative Instruments
Amount of Gain or (Loss) Recognized in Income on Derivatives Not Designated as Hedging Instruments	$ 4,425	$ (1,042)	$ (511)

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

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

Name:	us-gaap_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration