Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 584	$ 329	$ 1,645	$ 946
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	258	238	751	687
Unrealized/realized (gain) loss on fuel derivative instruments	87	63	172	(4)
Deferred income taxes	(82)	392	(40)	472
Changes in certain assets and liabilities:
Accounts and other receivables	4	(22)	(86)	(83)
Other assets	33	6	40	(7)
Accounts payable and accrued liabilities	380	(534)	424	(86)
Air traffic liability	(301)	(108)	617	806
Cash collateral received from (provided to) derivative counterparties	181	(98)	(213)	8
Other, net	(308)	(26)	(396)	(41)
Net cash provided by operating activities	836	240	2,914	2,698
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(230)	(406)	(1,231)	(1,282)
Assets constructed for others	(32)	(27)	(76)	(58)
Purchases of short-term investments	(506)	(415)	(1,383)	(2,344)
Proceeds from sales of short-term and other investments	509	805	1,732	2,427
Payments for (Proceeds from) Other Investing Activities	0	(1)	(9)	(2)
Net cash used in investing activities	(259)	(44)	(967)	(1,259)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Employee stock plans	9	23	30	96
Proceeds from termination of interest rate derivative instruments	0	0	12	0
Reimbursement for assets constructed for others	9	26	14	26
Payments of long-term debt and capital lease obligations	(79)	(48)	(170)	(167)
Payments of cash dividends	(49)	(41)	(180)	(138)
Repayment of construction obligation	(3)	(3)	(8)	(8)
Repurchase of common stock	(500)	(200)	(1,180)	(755)
Other, net	4	(3)	(7)	(16)
Net cash used in financing activities	(609)	(246)	(1,489)	(962)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(32)	(50)	458	477
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	1,772	1,882	1,282	1,355
CASH AND CASH EQUIVALENTS AT END OF PERIOD	1,740	1,832	1,740	1,832
CASH PAYMENTS FOR:
Interest, net of amount capitalized	33	35	86	102
Income taxes	409	132	975	144
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS
Flight equipment under capital leases	48	31	130	94
Assets constructed for others	$ 46	$ 27	$ 126	$ 59