FREQUENT FLYER PROGRAMS FREQUENT FLYER PROGRAMS (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Frequent Flyer Program [Line Items]
Other accrued liabilities	$ 979		$ 979		$ 878
Deferred revenue	652		652		640
Other liabilities	427		427		417
Passenger revenues	1,807	$ 1,263	3,291	$ 2,396
Other—net revenues	263	204	504	394
Frequent Flyer Program Revenue [Member]
Frequent Flyer Program [Line Items]
Passenger revenues	94	73	180	143
Other—net revenues	128	108	248	211
Frequent Flyer Program Revenue	222	$ 181	428	$ 354
Frequent Flyer Program Liabilities [Member]
Frequent Flyer Program [Line Items]
Other accrued liabilities	499		499		484
Deferred revenue	652		652		638
Other liabilities	23		23		21
Total	$ 1,174		$ 1,174		$ 1,143