Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Statement of Cash Flows [Abstract]
Net Cash Provided by Operating Activities	$ 4,381	$ 3,007
Property and equipment additions:
Flight equipment, including advance payments	(1,177)	(857)
Ground property and equipment, including technology	(328)	(275)
Purchase of short-term investments	(613)	(240)
Redemption of short-term investments	334	493
Other, net	17	37
Net cash used in investing activities	(1,767)	(842)
Cash Flows From Financing Activities:
Payments on long-term debt and capital lease obligations	(634)	(1,477)
Repurchase of common stock	(1,350)	(350)
Cash dividends	(147)	(101)
Fuel card obligation	(320)	1
Proceeds from long-term obligations	41	273
Other, net	1	7
Net cash used in financing activities	(2,409)	(1,647)
Net Increase in Cash and Cash Equivalents	205	518
Cash and cash equivalents at beginning of period	2,088	2,844
Cash and cash equivalents at end of period	2,293	3,362
Non-Cash Transactions:
Flight equipment under capital leases	$ 65	$ 28