CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net Income	$ 414	$ 645
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	290	275
Stock-based compensation and other	34	43
Changes in certain assets and liabilities:
Changes in deferred tax provision	122	208
Increase in air traffic liability	144	223
Increase in deferred revenue	106	130
Other—net	(124)	(167)
Net cash provided by operating activities	986	1,357
Property and equipment additions:
Aircraft and aircraft purchase deposits	(349)	(679)
Other flight equipment	(76)	(70)
Other property and equipment	(129)	(92)
Total property and equipment additions, including capitalized interest	(554)	(841)
Purchases of marketable securities	(672)	(1,408)
Sales and maturities of marketable securities	857	1,069
Other investing activities	36	38
Net cash used in investing activities	(333)	(1,142)
Cash flows from financing activities:
Long-term debt payments	(544)	(265)
Common stock repurchases	(37)	(50)
Dividends paid	(118)	(111)
Other financing activities	33	27
Net cash used in financing activities	(666)	(399)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(13)	(184)
Cash, cash equivalents, and restricted cash at beginning of year	197	328
Cash, cash equivalents, and restricted cash at end of the period	184	144
Cash paid during the period for:
Interest (net of amount capitalized)	60	68
Income taxes	$ 0	$ 129