Changes in Accumulated Other Comprehensive Income (Loss) (Reclassifications) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense)									$ (324,456)	$ (384,823)	$ (324,207)
Interest expense, net of interest capitalized									(332,422)	(355,785)	(382,416)
Depreciation and amortization expenses									(754,711)	(730,493)	(702,426)
Fuel									(924,414)	(909,691)	(764,758)
Net income	7,018	365,701	24,747	76,226	(392,803)	367,779	(3,653)	46,964	473,692	18,287	607,421
Reclassification out of accumulated other comprehensive income (loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income									67,010	107,155
Reclassification out of accumulated other comprehensive income (loss) | Gain (loss) on cash flow derivative hedges:
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net income									69,599	109,385
Reclassification out of accumulated other comprehensive income (loss) | Gain (loss) on cash flow derivative hedges: | Cross currency swaps
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense)									0	2,505
Interest expense, net of interest capitalized									(3,531)	(2,209)
Reclassification out of accumulated other comprehensive income (loss) | Gain (loss) on cash flow derivative hedges: | Foreign currency forward contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other income (expense)									27,423	(953)
Interest expense, net of interest capitalized									(440)	0
Depreciation and amortization expenses									(1,797)	(953)
Reclassification out of accumulated other comprehensive income (loss) | Gain (loss) on cash flow derivative hedges: | Fuel contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Fuel									47,944	110,995
Reclassification out of accumulated other comprehensive income (loss) | Amortization of defined benefit plans:
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of defined benefit plans:									(1,753)	(1,394)
Actuarial loss									(836)	(836)
Net income									$ (2,589)	$ (2,230)