Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements and Derivatives - Effects of Derivatives Designated as Cash flow Hedges (Details)

v3.19.2
Fair Value Measurements and Derivatives - Effects of Derivatives Designated as Cash flow Hedges (Details) - Cash Flow Hedging - 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]        
Amount of Gain (Loss) Recognized in Other Comprehensive Income $ (17,189) $ (15,894) $ (2,037) $ 32,682
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income 9,274 6,723 16,274 8,508
Fuel contracts | Fuel        
Derivative Instruments, Gain (Loss) [Line Items]        
Amount of Gain (Loss) Recognized in Other Comprehensive Income (16,577) 70,508 79,931 64,496
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income 9,885 7,904 17,403 11,429
Foreign currency contracts | Depreciation and amortization expense        
Derivative Instruments, Gain (Loss) [Line Items]        
Amount of Gain (Loss) Recognized in Other Comprehensive Income 4,181 (88,382) (76,097) (33,889)
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income (703) (899) (1,406) (2,058)
Interest rate contracts | Interest expense, net        
Derivative Instruments, Gain (Loss) [Line Items]        
Amount of Gain (Loss) Recognized in Other Comprehensive Income (4,793) 1,980 (5,871) 2,075
Amount of gain or (loss) reclassified from accumulated other comprehensive income (loss) into income $ 92 $ (282) $ 277 $ (863)