FREQUENT FLYER PROGRAMS FREQUENT FLYER PROGRAMS (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Frequent Flyer Program [Line Items]
Other accrued liabilities	$ 886		$ 886		$ 878
Deferred revenue	682		682		640
Other liabilities	429		429		417
Passenger revenues	1,824	$ 1,322	5,115	$ 3,718
Other—net revenues	264	213	768	607
Frequent Flyer Program Revenue [Member]
Frequent Flyer Program [Line Items]
Passenger revenues	94	73	276	215
Other—net revenues	122	107	369	318
Frequent Flyer Program Revenue	216	$ 180	645	$ 533
Frequent Flyer Program Liabilities [Member]
Frequent Flyer Program [Line Items]
Other accrued liabilities	509		509		484
Deferred revenue	682		682		638
Other liabilities	24		24		21
Total	$ 1,215		$ 1,215		$ 1,143