NET INCOME PER SHARE (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended												12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Notes to Financial Statements [Abstract]
Net income (loss)	$ 78	$ 16	$ 228	$ 98	$ 152	[1]	$ (140)	[1]	$ 161	[1]	$ 5	[1]	$ 421	$ 178	$ 459
Income effect of assumed-conversion interest on 5.25% convertible notes													3	0	0
Net income (loss) available to common stockholders, Diluted													$ 424	$ 178	$ 459
Weighted average shares outstanding, basic													750	774	746
Dilutive effect of Employee stock options and restricted stock units (in millions of shares)													1	1	1
Dilutive effect of 5.25% convertible notes													6	0	0
Weighted average number of shares outstanding, diluted													757	775	747
NET INCOME (LOSS) PER SHARE [Abstract]
Net income per share, basic	$ 0.11	$ 0.02	$ 0.30	$ 0.13	$ 0.20	[1]	$ (0.18)	[1]	$ 0.21	[1]	$ 0.01	[1]	$ 0.56	$ 0.23	$ 0.62
Net income per share, diluted	$ 0.11	$ 0.02	$ 0.30	$ 0.13	$ 0.20	[1]	$ (0.18)	[1]	$ 0.21	[1]	$ 0.01	[1]	$ 0.56	$ 0.23	$ 0.61
Stock Options and Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially diluted amounts excluded from calculations													35	48	62
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially diluted amounts excluded from calculations													0	6	0

[1] Includes the results of AirTran for May 2011 through December 2011. See Note 2 to the Consolidated Financial Statements for further information.