Condensed Consolidated Statement of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 511	$ 453
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	290	244
Unrealized/realized (gain) loss on fuel derivative instruments	88	11
Deferred income taxes	26	19
Changes in certain assets and liabilities:
Accounts and other receivables	(21)	(130)
Other assets	4	13
Accounts payable and accrued liabilities	313	177
Air traffic liability	685	717
Cash collateral provided to derivative counterparties	(231)	(17)
Other, net	(49)	(35)
Net cash provided by operating activities	1,616	1,452
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(438)	(573)
Assets constructed for others	(11)	(22)
Purchases of short-term investments	(256)	(316)
Proceeds from sales of short-term and other investments	530	609
Net cash used in investing activities	(175)	(302)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from Employee stock plans	11	13
Proceeds from termination of interest rate derivative instruments	0	12
Reimbursement for assets constructed for others	10	2
Payments of long-term debt and capital lease obligations	(56)	(51)
Payments of cash dividends	(96)	(81)
Repayment of construction obligation	(2)	(2)
Repurchase of common stock	(500)	(300)
Other, net	(3)	0
Net cash used in financing activities	(636)	(407)
NET CHANGE IN CASH AND CASH EQUIVALENTS	805	743
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	1,583	1,282
CASH AND CASH EQUIVALENTS AT END OF PERIOD	2,388	2,025
CASH PAYMENTS FOR:
Interest, net of amount capitalized	27	32
Income taxes	73	111
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS
Flight equipment under capital leases	169	41
Assets constructed for others	$ 60	$ 43