Fair Value Measurements and Derivatives - Effects of Foreign Currency Collar Designated as Cash Flow Hedges (Details 6) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Cash Flow Hedging \| Designated as Hedging Instrument \| Foreign Currency Collar
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from accumulated other comprehensive income (loss) into depreciation and amortization expense	$ (91)	$ (91)

The effective portion of loss reclassified from accumulated other comprehensive income into income on derivative instruments designated and 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 (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Name:	us-gaap_DerivativeInstrumentsLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortion
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration