COMPREHENSIVE INCOME (LOSS) (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive income (loss) [Abstract]
Net income (loss)	$ (140)	$ 205	$ 26	$ 328
Unrealized gain (loss) on fuel derivative instruments, net of deferred taxes	(372)	199	(219)	160
Unrealized gain (loss) on interest rate swaps, net of deferred taxes	(30)	(12)	(34)	(34)
Other, net of deferred taxes	(4)	1	2	(1)
Total Other comprehensive income	(406)	188	(251)	125
Total comprehensive income	(546)	393	(225)	453
Deferred taxes on unrealized gain (loss) on fuel derivative instruments	(233)	124	(137)	100
Deferred taxes on unrealized gain (loss) on interest rate derivative instruments	(19)	(7)	(22)	(21)
Deferred taxes on Other	(3)	1	1	0
Accumulated Other Comprehensive Income Loss Net of Tax [Line Items]
Beginning Balance	(107)		(262)
2011 changes in fair value	(451)		(329)
Reclassification to earnings	45		78
Ending Balance	(513)		(513)
Fuel hedge derivatives [Member]
Accumulated Other Comprehensive Income Loss Net of Tax [Line Items]
Beginning Balance	(97)		(250)
2011 changes in fair value	(417)		(297)
Reclassification to earnings	45		78
Ending Balance	(469)		(469)
Interest rate derivatives [Member]
Accumulated Other Comprehensive Income Loss Net of Tax [Line Items]
Beginning Balance	(38)		(34)
2011 changes in fair value	(30)		(34)
Reclassification to earnings	0		0
Ending Balance	(68)		(68)
Other [Member]
Accumulated Other Comprehensive Income Loss Net of Tax [Line Items]
Beginning Balance	28		22
2011 changes in fair value	(4)		2
Reclassification to earnings	0		0
Ending Balance	$ 24		$ 24