MILEAGE PLAN MILEAGE PLAN (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Mileage Plan [Line Items]
Other accrued liabilities	$ 736		$ 736		$ 629
Deferred revenue	401		401		374
Other liabilities	339		339		327
Passenger revenues	1,231	$ 1,174	2,318	$ 2,214
Other - net revenues	176	169	335	327
Liabilities From Mileage Plan [Member]
Mileage Plan [Line Items]
Other accrued liabilities	352		352		343
Deferred revenue	395		395		367
Other liabilities	20		20		20
Total	767		767		$ 730
Revenue From Mileage Plan [Member]
Mileage Plan [Line Items]
Passenger revenues	69	62	134	118
Other - net revenues	82	73	159	146
Total Mileage Plan Revenues	$ 151	$ 135	$ 293	$ 264