Consolidated Statement of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 2,300	$ 2,465	$ 3,357
Adjustments to reconcile net income to cash provided by (used in) operating activities:
Depreciation and amortization	1,219	1,201	1,218
Boeing 737-300 aircraft grounding charge	0	0	63
Unrealized/realized gains on fuel derivative instruments	0	(14)	(50)
Deferred income taxes	(55)	301	(1,066)
Changes in certain assets and liabilities:
Accounts and other receivables	(94)	117	(102)
Other assets	239	(227)	(262)
Accounts payable and accrued liabilities	298	545	233
Air traffic liability	440	506	343
Other liabilities	(277)	0	0
Cash collateral received from (provided to) derivative counterparties	25	(15)	316
Other, net	(108)	14	(121)
Net cash provided by operating activities	3,987	4,893	3,929
Net cash used in investing activities
Capital expenditures	(1,027)	(1,922)	(2,123)
Supplier proceeds	400	0	0
Assets constructed for others	0	(54)	(126)
Purchases of short-term investments	(2,122)	(2,409)	(2,380)
Proceeds from sale of short-term and other investments	2,446	2,342	2,221
Other, net	0	5	0
Net cash used in investing activities	(303)	(2,038)	(2,408)
Net cash used in financing activities
Proceeds from issuance of long-term debt	0	0	600
Proceeds from Employee stock plans	40	35	29
Reimbursement for assets constructed for others	0	170	126
Payments of long-term debt and finance lease obligations	(615)	(342)	(592)
Payments of cash dividends	372	332	274
Repayment of construction obligation	0	(30)	(10)
Repurchase of common stock	(2,000)	(2,000)	(1,600)
Other, net	(43)	3	15
Net cash used in financing activities	(2,990)	(2,496)	(1,706)
NET CHANGE IN CASH AND CASH EQUIVALENTS	694	359	(185)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	1,854	1,495	1,680
CASH AND CASH EQUIVALENTS AT END OF PERIOD	2,548	1,854	1,495
CASH PAYMENTS FOR:
Interest, net of amount capitalized	88	107	81
Income taxes	779	327	992
SUPPLEMENTAL DISCLOSURE OF NONCASH TRANSACTIONS:
Flight equipment under finance leases	1	32	233
Assets constructed for others	65	171	197
Supplier receivables	$ 428	$ 0	$ 0