MILEAGE PLAN MILEAGE PLAN (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Mileage Plan [Line Items]
Other accrued liabilities	$ 809		$ 661
Deferred revenue	467		431
Other liabilities	359		362
Passenger revenues	1,133	$ 1,087
Other - net revenues	190	159
Liabilities From Mileage Plan [Member]
Mileage Plan [Line Items]
Other accrued liabilities	388		368
Deferred revenue	464		427
Other liabilities	19		19
Total	871		$ 814
Revenue From Mileage Plan [Member]
Mileage Plan [Line Items]
Passenger revenues	69	64
Other - net revenues	103	76
Total Mileage Plan Revenues	$ 172	$ 140