Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements and Derivatives - Effects of cash flow hedge accounting on consolidated statements of operations (Details)

v3.19.2
Fair Value Measurements and Derivatives - Effects of cash flow hedge accounting on consolidated statements of operations (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Derivative Instruments Gain Loss [Line Items]        
Fuel $ 100,531 $ 95,212 $ 198,784 $ 188,643
Depreciation and amortization 156,271 140,704 326,012 271,948
Interest expense, net 65,969 72,988 139,472 132,686
Cash Flow Hedging        
Derivative Instruments Gain Loss [Line Items]        
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income 9,274 6,723 16,274 8,508
Cash Flow Hedging | Foreign currency contracts | Depreciation and amortization expense        
Derivative Instruments Gain Loss [Line Items]        
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income (703) (899) (1,406) (2,058)
Cash Flow Hedging | Interest rate contracts | Interest expense, net        
Derivative Instruments Gain Loss [Line Items]        
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income $ 92 $ (282) $ 277 $ (863)