Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 388	$ 584	$ 1,722	$ 1,645
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	315	258	903	751
Loss as asset impairment	0	0	21	0
Unrealized/realized (gain) loss on fuel derivative instruments	(67)	87	(101)	172
Deferred income taxes	315	(82)	395	(40)
Changes in certain assets and liabilities:
Accounts and other receivables	(320)	4	(355)	(86)
Other assets	(16)	33	(61)	40
Accounts payable and accrued liabilities	247	380	272	424
Air traffic liability	(77)	(301)	686	617
Cash collateral received from (provided to) derivative counterparties	114	181	230	(213)
Other, net	(43)	(308)	(128)	(396)
Net cash provided by operating activities	856	836	3,584	2,914
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(464)	(230)	(1,364)	(1,231)
Assets constructed for others	(33)	(32)	(70)	(76)
Purchases of short-term investments	(641)	(506)	(1,670)	(1,383)
Proceeds from sales of short-term and other investments	549	509	1,671	1,732
Payments for (Proceeds from) Other Investing Activities	5	0	0	(9)
Net cash used in investing activities	(584)	(259)	(1,433)	(967)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Employee stock plans	6	9	23	30
Proceeds from termination of interest rate derivative instruments	0	0	0	12
Reimbursement for assets constructed for others	33	9	68	14
Payments of long-term debt and capital lease obligations	(68)	(79)	(171)	(170)
Payments of cash dividends	(62)	(49)	(222)	(180)
Repayment of construction obligation	(2)	(3)	(6)	(8)
Repurchase of common stock	(250)	(500)	(1,450)	(1,180)
Other, net	(3)	4	(10)	(7)
Net cash used in financing activities	(346)	(609)	(1,768)	(1,489)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(74)	(32)	383	458
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	2,040	1,772	1,583	1,282
CASH AND CASH EQUIVALENTS AT END OF PERIOD	1,966	1,740	1,966	1,740
CASH PAYMENTS FOR:
Interest, net of amount capitalized	27	33	77	86
Income taxes	264	409	902	975
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS
Noncash or Part Noncash Acquisition, Debt Assumed	20	0	20	0
Flight equipment under capital leases	0	48	251	130
Assets constructed for others	$ 50	$ 46	$ 165	$ 126