CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net Income	$ 266	$ 197
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	211	191
Stock-based compensation and other	16	17
Changes in certain assets and liabilities:
Changes in deferred tax provision	62	67
Increase in air traffic liability	385	306
Increase in deferred revenue	75	52
Other—net	18	(104)
Net cash provided by operating activities	1,033	726
Property and equipment additions:
Aircraft and aircraft purchase deposits	(172)	(271)
Other flight equipment	(83)	(56)
Other property and equipment	(78)	(96)
Total property and equipment additions, including capitalized interest	(333)	(423)
Purchases of marketable securities	(885)	(529)
Sales and maturities of marketable securities	663	474
Other investing activities	25	10
Net cash used in investing activities	(530)	(468)
Cash flows from financing activities:
Proceeds from issuance of debt	254	0
Long-term debt payments	(532)	(258)
Common stock repurchases	(25)	(25)
Dividends paid	(86)	(79)
Other financing activities	26	15
Net cash used in financing activities	(363)	(347)
Net increase (decrease) in cash, cash equivalents, and restricted cash	140	(89)
Cash, cash equivalents, and restricted cash at beginning of year	114	197
Cash, cash equivalents, and restricted cash at end of the period	254	108
Cash paid during the period for:
Interest (net of amount capitalized)	34	39
Income taxes	$ 0	$ 0