Fair Value Measurements and Derivative Instruments (Designated Cash Flow Hedges) (Details) (Cash flow hedge, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
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)	$ 197,428	$ 58,138
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	69,599	109,385
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	(2,973)	(1,389)
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)	0	851
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	0	2,505
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	0	0
Cross currency swaps | Interest 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)	0	0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(3,531)	(2,209)
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)	111,223	(44,971)
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	0	0
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	431	(348)
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)	0	0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	27,423	(953)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	0	0
Foreign currency forward contracts | Interest 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)	0	0
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(440)	0
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)	68,364	11,928
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	(1,797)	(953)
Amount of Gain (Loss) Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness testing)	9	0
Foreign currency collar options | 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)	0	0
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)	13,199	3,316
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	0	0
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)	(3,413)	(1,041)
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)	4,642	87,014
Amount of Gain (Loss) Reclassified from Accumulated OCI into Income (Effective Portion)	$ 47,944	$ 110,995