Fair Value Measurements and Derivative Instruments - Designated Cash Flow Hedges (Details) - Cash flow hedge - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	$ 14,913	$ (300,302)	$ (9,150)	$ (483,946)
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	(80,623)	(77,810)	(263,774)	(202,978)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	82	(2,970)	(5,158)	(3,166)
Interest rate swaps | Other income (expense)
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	90	(617)	(1,152)	(395)
Interest rate swaps
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	6,598	(68,956)	(126,505)	(75,104)
Interest rate swaps | Interest expense, net of interest capitalized
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	(11,953)	(10,276)	(32,019)	(27,024)
Foreign currency forward contracts
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	11,405	(619)	22,715	(131,211)
Foreign currency forward contracts | Other income (expense)
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	(3,465)	(239)	(10,206)	(715)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	0		(57)
Foreign currency forward contracts | Other operating expenses
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	0	0	(207)	0
Foreign currency forward contracts | Depreciation and amortization expenses
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	(2,710)	(752)	(5,408)	(2,153)
Foreign currency collar options
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	0	34	0	(64,559)
Foreign currency collar options | Depreciation and amortization expenses
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	(601)	(568)	(1,806)	(1,003)
Fuel swaps
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	(3,090)	(230,761)	94,640	(213,072)
Fuel swaps | Other income (expense)
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	2,760		9,356	0
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing)	(8)	(2,353)	(3,949)	(2,771)
Fuel swaps | Fuel cost
Effect of derivative instruments involved in hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Income into Income (Effective Portion)	$ (64,654)	$ (65,975)	$ (223,484)	$ (172,083)