Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 608	$ 465	$ 1,061	$ 617
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	250	228	494	449
Unrealized/realized (gain) loss on fuel derivative instruments	74	(7)	85	(67)
Deferred income taxes	23	(11)	43	81
Changes in certain assets and liabilities:
Accounts and other receivables	41	10	(90)	(61)
Other assets	(7)	(21)	6	(14)
Accounts payable and accrued liabilities	(134)	424	43	448
Air traffic liability	201	153	918	914
Cash collateral received from (provided to) derivative counterparties	(377)	95	(394)	106
Other, net	(52)	2	(87)	(15)
Net cash provided by operating activities	627	1,338	2,079	2,458
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(428)	(481)	(1,001)	(876)
Assets constructed for others	(22)	(19)	(44)	(31)
Purchases of short-term investments	(562)	(1,159)	(877)	(1,929)
Proceeds from sales of short-term and other investments	614	803	1,223	1,622
Payments for (Proceeds from) Other Investing Activities	(9)	(1)	(9)	(1)
Net cash used in investing activities	(407)	(857)	(708)	(1,215)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Employee stock plans	8	25	21	73
Proceeds from termination of interest rate derivative instruments	0	0	12	0
Reimbursement for assets constructed for others	3	0	5	0
Payments of long-term debt and capital lease obligations	(40)	(73)	(92)	(119)
Payments of cash dividends	(50)	(42)	(131)	(97)
Repayment of construction obligation	(3)	(2)	(5)	(5)
Repurchase of common stock	(380)	(240)	(680)	(555)
Other, net	(11)	(8)	(11)	(13)
Net cash used in financing activities	(473)	(340)	(881)	(716)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(253)	141	490	527
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	2,025	1,741	1,282	1,355
CASH AND CASH EQUIVALENTS AT END OF PERIOD	1,772	1,882	1,772	1,882
CASH PAYMENTS FOR:
Interest, net of amount capitalized	21	33	53	67
Income taxes	455	12	566	12
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS
Assets constructed for others	$ 37	$ 19	$ 80	$ 31