CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net Income	$ 848	$ 605	$ 508
Adjustments to reconcile net income to net cash provided by operating activities:
Special mileage plan accounting adjustment	0	0	(192)
Depreciation and amortization	320	294	270
Stock-based compensation and other	25	6	32
Changes in certain assets and liabilities:
Changes in deferred income taxes	(56)	(114)	(146)
(Increase) decrease in accounts receivable	47	(110)	(19)
Increase (decrease) in air traffic liability	38	67	29
Increase (decrease) in deferred revenue	57	40	84
Increase (Decrease) in Pension Plan Obligations	36	(18)	62
Other - net	157	32	148
Pension contribution	0	0	87
Net cash provided by operating activities	1,584	1,030	981
Property and equipment additions:
Aircraft and aircraft purchase deposits	(681)	(498)	(487)
Other flight equipment	(79)	(131)	(41)
Other property and equipment	(71)	(65)	(38)
Total property and equipment additions	(831)	(694)	(566)
Purchases of marketable securities	(1,327)	(949)	(1,218)
Sales and maturities of marketable securities	1,175	1,092	1,089
Proceeds from disposition of assets and changes in restricted deposits	53	10	(3)
Net cash used in investing activities	(930)	(541)	(698)
Cash flows from financing activities:
Proceeds from issuance of long-term debt	0	51	0
Long-term debt payments	(116)	(119)	(161)
Common stock repurchases	(505)	(348)	(159)
Cash dividend paid	(102)	(68)	(28)
Other financing activities	35	22	23
Net cash used in financing activities	(688)	(462)	(325)
Net increase (decrease) in cash and cash equivalents	(34)	27	(42)
Cash and cash equivalents at beginning of year	107	80	122
Cash and cash equivalents at end of year	73	107	80
Cash paid during the year for:
Interest (net of amount capitalized)	8	28	35
Income taxes	$ 349	$ 326	$ 149