Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements and Derivatives (Details 3)

v3.8.0.1
Fair Value Measurements and Derivatives (Details 3) - Cash Flow Hedging - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Derivatives Fair Value [Line Items]    
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income $ 1,785 $ (9,705)
Fuel Swaps | Fuel    
Derivatives Fair Value [Line Items]    
Total amounts of income and expense line items presented in the consolidated statements of operations in which the effects of cash flow hedges are recorded 93,431 88,886
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income 3,525 (8,003)
Foreign currency forward contracts | Depreciation and amortization expense    
Derivatives Fair Value [Line Items]    
Total amounts of income and expense line items presented in the consolidated statements of operations in which the effects of cash flow hedges are recorded 131,244 119,205
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income (1,159) (857)
Interest Rate Swap | Interest expense, net    
Derivatives Fair Value [Line Items]    
Total amounts of income and expense line items presented in the consolidated statements of operations in which the effects of cash flow hedges are recorded 59,698 52,960
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income $ (581) $ (845)