Fair Value Measurements and Derivative Instruments (Details 9) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Cross currency swaps | Interest Expense
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ (498)		$ (1,319)
Cash flow hedge
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	119,127	(259,458)	28,740	72,380
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	37,805	(4,443)	88,200	118,620
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	3,109	(2,656)	(1,093)	6,802
Cash flow hedge | Cross currency swaps | Other income (expense)
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	13,221	(31,964)	851	6,614
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	14,405	(44,600)	2,505	120
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	234
Cash flow hedge | Interest rate swaps | Other income (expense)
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	(19,146)		(50,070)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	(277)		(347)
Cash flow hedge | Foreign currency forward contracts | Other income (expense)
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)				(12,375)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(238)	(238)	(715)	(47)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	(173)	(2,879)	(182)	(190)
Cash flow hedge | Foreign currency forward contracts | Depreciation and amortization expenses
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	19,881	(102,142)	(10,169)	10,014
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(196)	(189)	(588)	(538)
Cash flow hedge | Foreign currency collar options | Depreciation and amortization expenses
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	4,229		(8,335)
Cash flow hedge | Fuel contracts | Swaps | Other income (expense)
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	3,325	223	(564)	6,992
Cash flow hedge | Fuel contracts | Swaps | Fuel cost
Effect of derivative instruments involved in cash flow hedging on the consolidated financial statements
Amount of Gain (Loss) Recognized in OCI on Derivative (Effective Portion)	100,942	(125,352)	96,463	68,127
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ 24,332	$ 40,584	$ 88,317	$ 119,085