Changes in Accumulated Other Comprehensive (Loss) Income - Reclassifications (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassifications out of accumulated other comprehensive loss
Interest expense, net of interest capitalized	$ (218,889)	$ (111,304)	$ (311,800)	$ (211,719)
Depreciation and amortization expenses	(319,757)	(311,600)	(644,087)	(603,885)
Other expense	(83,825)	(21,781)	(116,684)	(26,869)
Fuel	(79,192)	(181,924)	(273,460)	(342,095)
Other expense	(680,420)	(1,544,504)	(2,191,239)	(2,958,208)
Other operating
Reclassifications out of accumulated other comprehensive loss
Other expense	(279,465)	(348,801)	(703,463)	(694,943)
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income
Reclassifications out of accumulated other comprehensive loss
Total reclassifications for the period	(57,745)	6,725	(80,630)	19,259
Loss on cash flow derivative hedges | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income
Reclassifications out of accumulated other comprehensive loss
Total reclassifications for the period	(22,917)	6,920	(45,297)	19,642
Loss on cash flow derivative hedges | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income | Interest rate swaps
Reclassifications out of accumulated other comprehensive loss
Interest expense, net of interest capitalized	(6,016)	(409)	(9,407)	(800)
Loss on cash flow derivative hedges | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income | Foreign currency forward contracts
Reclassifications out of accumulated other comprehensive loss
Depreciation and amortization expenses	(3,780)	(3,545)	(7,117)	(6,879)
Other expense	(2,581)	(1,300)	(4,344)	(2,615)
Loss on cash flow derivative hedges | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income | Fuel swaps
Reclassifications out of accumulated other comprehensive loss
Other expense	2,149	(1,188)	2,493	(1,444)
Fuel	(12,689)	13,362	(26,922)	31,380
Changes in defined benefit plans | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income
Reclassifications out of accumulated other comprehensive loss
Payroll and related	(528)	(195)	(1,033)	(383)
Total reclassifications for the period	(528)	(195)	(1,033)	(383)
Foreign cumulative translation | Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income (Loss) into Income | Other operating
Reclassifications out of accumulated other comprehensive loss
Other expense	$ (34,300)	$ 0	$ (34,300)	$ 0