Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash Flows From Operating Activities:
Net (loss)/income	$ (12,385)	$ 4,767	$ 3,935
Adjustments to reconcile net income to net cash provided by operating activities:
Restructuring charges	4,111	0	0
Depreciation and amortization	2,312	2,581	2,329
Deferred income taxes	(3,110)	1,473	1,364
Pension, postretirement and postemployment payments less/(greater) than expense	898	(922)	(790)
Impairments and equity method losses	2,432	62	60
Changes in certain assets and liabilities:
Receivables	1,168	(775)	108
Fuel inventory	354	(139)	324
Noncurrent assets	210	111	(221)
Profit sharing	(1,650)	354	233
Other payables, deferred revenue and accrued liabilities	240	144	(418)
Noncurrent liabilities	1,185	(16)	47
Other, net	559	244	(573)
Net cash (used in)/provided by operating activities	(3,793)	8,425	7,014
Property and equipment additions:
Flight equipment, including advance payments	(896)	(3,344)	(3,704)
Ground property and equipment, including technology	(1,003)	(1,592)	(1,464)
Proceeds from sale-leaseback transactions	465	0	0
Purchase of equity investments	(2,099)	(170)	0
Sale of equity investments	0	279	28
Purchase of short-term investments	(13,400)	0	(145)
Redemption of short-term investments	7,608	206	766
Other, net	87	58	126
Net cash used in investing activities	(9,238)	(4,563)	(4,393)
Cash Flows From Financing Activities:
Proceeds from short-term obligations	3,261	1,750	0
Proceeds from long-term obligations	22,790	2,057	3,745
Proceeds from sale-leaseback transactions	2,306	0	0
Payments on debt and finance lease obligations	(8,559)	(3,320)	(3,052)
Repurchase of common stock	(344)	(2,027)	(1,575)
Cash dividends	(260)	(980)	(909)
Fuel card obligation	364		7
Fuel card obligation		(339)
Other, net	(202)	(21)	58
Net cash provided by/(used in) financing activities	19,356	(2,880)	(1,726)
Net Increase in Cash, Cash Equivalents and Restricted Cash	6,325	982	895
Cash, cash equivalents and restricted cash at beginning of period	3,730	2,748	1,853
Cash, cash equivalents and restricted cash at end of period	10,055	3,730	2,748
Supplemental Disclosure of Cash Paid for Interest	761	481	376
Non-Cash Transactions:
Right-of-use assets acquired under operating leases	1,077	464	1,041
Flight and ground equipment acquired under finance leases	381	650	93
Operating leases converted to finance leases	0	190	7
Air traffic
Changes in certain assets and liabilities:
Liabilities and deferred revenue	(572)	454	297
Loyalty program
Changes in certain assets and liabilities:
Liabilities and deferred revenue	$ 455	$ 87	$ 319