MILEAGE PLAN MILEAGE PLAN (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Mileage Plan [Line Items]
Other accrued liabilities	$ 698		$ 698		$ 629
Deferred revenue	416		416		374
Other liabilities	341		341		327
Passenger revenues	1,297	$ 1,249	3,615	$ 3,463
Other - net revenues	188	184	523	511
Liabilities From Mileage Plan [Member]
Mileage Plan [Line Items]
Other accrued liabilities	368		368		343
Deferred revenue	410		410		367
Other liabilities	20		20		20
Total	798		798		$ 730
Revenue From Mileage Plan [Member]
Mileage Plan [Line Items]
Passenger revenues	66	62	199	180
Other - net revenues	85	77	244	223
Total Mileage Plan Revenues	$ 151	$ 139	$ 443	$ 403