Fair Value Measurements and Derivatives - Effects of Foreign Currency Collar Designated as Cash Flow Hedges (Details 8) - USD ($) $ in Thousands  | 
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2016  | 
Jun. 30, 2015  | 
Jun. 30, 2016  | 
Jun. 30, 2015  | 
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| 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) | $ (182) | $ (182) | 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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- Definition 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 
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