Revenue Recognition (Revenue Categories) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Total operating revenues	$ 42,340	$ 44,588	$ 126,069	$ 134,372
Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	14,365	14,435	42,975	42,984
Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	5,490	5,399	16,310	15,985
Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	2,707	2,886	8,330	8,962
Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	10,081	11,267	30,617	33,954
Content
Disaggregation of Revenue [Line Items]
Total operating revenues	2,130	3,115	6,965	9,850
Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	1,679	1,523	4,456	5,136
Other
Disaggregation of Revenue [Line Items]
Total operating revenues	1,330	1,692	4,063	5,153
Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	4,558	4,271	12,353	12,348
Operating Segments
Disaggregation of Revenue [Line Items]
Total operating revenues	43,197	45,481	128,522	137,032
Operating Segments | Communications
Disaggregation of Revenue [Line Items]
Total operating revenues	34,287	35,401	102,128	105,837
Operating Segments | Communications | Mobility
Disaggregation of Revenue [Line Items]
Total operating revenues	17,894	17,701	52,445	52,356
Operating Segments | Communications | Mobility | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	13,811	13,856	41,314	41,171
Operating Segments | Communications | Mobility | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Mobility | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Mobility | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Mobility | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Mobility | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	72	74	206	212
Operating Segments | Communications | Mobility | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Mobility | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	4,011	3,771	10,925	10,973
Operating Segments | Communications | Entertainment Group
Disaggregation of Revenue [Line Items]
Total operating revenues	10,053	11,197	30,637	33,893
Operating Segments | Communications | Entertainment Group | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Entertainment Group | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	2,128	2,117	6,329	6,296
Operating Segments | Communications | Entertainment Group | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	538	628	1,679	1,969
Operating Segments | Communications | Entertainment Group | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	6,556	7,512	20,220	22,872
Operating Segments | Communications | Entertainment Group | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Entertainment Group | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	408	421	1,115	1,170
Operating Segments | Communications | Entertainment Group | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	373	517	1,189	1,580
Operating Segments | Communications | Entertainment Group | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	50	2	105	6
Operating Segments | Communications | Business Wireline
Disaggregation of Revenue [Line Items]
Total operating revenues	6,340	6,503	19,046	19,588
Operating Segments | Communications | Business Wireline | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Business Wireline | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	3,348	3,269	9,943	9,649
Operating Segments | Communications | Business Wireline | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	2,031	2,252	6,227	6,973
Operating Segments | Communications | Business Wireline | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Business Wireline | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Business Wireline | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Communications | Business Wireline | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	780	783	2,315	2,430
Operating Segments | Communications | Business Wireline | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	181	199	561	536
Operating Segments | WarnerMedia
Disaggregation of Revenue [Line Items]
Total operating revenues	7,514	8,350	22,176	25,990
Operating Segments | WarnerMedia | Turner
Disaggregation of Revenue [Line Items]
Total operating revenues	3,176	3,007	9,326	9,860
Operating Segments | WarnerMedia | Turner | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Turner | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Turner | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Turner | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	1,840	1,927	5,693	5,835
Operating Segments | WarnerMedia | Turner | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	175	89	595	335
Operating Segments | WarnerMedia | Turner | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	1,077	913	2,830	3,440
Operating Segments | WarnerMedia | Turner | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	84	78	208	250
Operating Segments | WarnerMedia | Turner | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Home Box Office
Disaggregation of Revenue [Line Items]
Total operating revenues	1,781	1,819	4,905	5,045
Operating Segments | WarnerMedia | Home Box Office | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Home Box Office | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Home Box Office | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Home Box Office | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	1,624	1,533	4,403	4,383
Operating Segments | WarnerMedia | Home Box Office | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	150	284	488	655
Operating Segments | WarnerMedia | Home Box Office | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Home Box Office | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	7	2	14	7
Operating Segments | WarnerMedia | Home Box Office | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Warner Bros.
Disaggregation of Revenue [Line Items]
Total operating revenues	2,411	3,333	8,907	10,240
Operating Segments | WarnerMedia | Warner Bros. | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Warner Bros. | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Warner Bros. | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | WarnerMedia | Warner Bros. | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	11	23	37	67
Operating Segments | WarnerMedia | Warner Bros. | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	2,293	3,129	8,532	9,636
Operating Segments | WarnerMedia | Warner Bros. | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	1	13	4	33
Operating Segments | WarnerMedia | Warner Bros. | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	106	168	334	504
Operating Segments | WarnerMedia | Warner Bros. | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America
Disaggregation of Revenue [Line Items]
Total operating revenues	1,396	1,730	4,218	5,205
Operating Segments | Latin America | Vrio
Disaggregation of Revenue [Line Items]
Total operating revenues	753	1,013	2,392	3,112
Operating Segments | Latin America | Vrio | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	753	1,013	2,392	3,112
Operating Segments | Latin America | Vrio | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Vrio | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico
Disaggregation of Revenue [Line Items]
Total operating revenues	643	717	1,826	2,093
Operating Segments | Latin America | Mexico | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	385	455	1,197	1,376
Operating Segments | Latin America | Mexico | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Operating Segments | Latin America | Mexico | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	258	262	629	717
Eliminations and other | WarnerMedia
Disaggregation of Revenue [Line Items]
Total operating revenues	146	191	(962)	845
Eliminations and other | WarnerMedia | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0		0	0
Eliminations and other | WarnerMedia | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0		0	0
Eliminations and other | WarnerMedia | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0		0	0
Eliminations and other | WarnerMedia | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	87		221	160
Eliminations and other | WarnerMedia | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	(488)		(2,650)	(776)
Eliminations and other | WarnerMedia | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	529		1,416	1,451
Eliminations and other | WarnerMedia | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	18		51	10
Eliminations and other | WarnerMedia | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0		0	0
Eliminations and other | WarnerMedia | Warner Bros. | Content sales with HBO Max
Disaggregation of Revenue [Line Items]
Total operating revenues	(200)		(1,850)
Eliminations and other | WarnerMedia | Warner Bros. | Content sales with HBO Linear
Disaggregation of Revenue [Line Items]
Total operating revenues	(180)	(110)	(510)	(310)
Eliminations and other | WarnerMedia | Warner Bros. | Content sales with Turner
Disaggregation of Revenue [Line Items]
Total operating revenues	(100)	(170)	(220)	(290)
Corporate and Other
Disaggregation of Revenue [Line Items]
Total operating revenues	431	407	1,256	1,218
Corporate and Other | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	169	124	464	437
Corporate and Other | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	14	13	38	40
Corporate and Other | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	138	6	424	20
Corporate and Other | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Corporate and Other | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Corporate and Other | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Corporate and Other | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	52	227	197	605
Corporate and Other | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	58	37	133	116
Corporate and Other | WarnerMedia
Disaggregation of Revenue [Line Items]
Total operating revenues		191
Corporate and Other | WarnerMedia | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues		0
Corporate and Other | WarnerMedia | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues		0
Corporate and Other | WarnerMedia | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues		0
Corporate and Other | WarnerMedia | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues		57
Corporate and Other | WarnerMedia | Content
Disaggregation of Revenue [Line Items]
Total operating revenues		(387)
Corporate and Other | WarnerMedia | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues		523
Corporate and Other | WarnerMedia | Other
Disaggregation of Revenue [Line Items]
Total operating revenues		(2)
Corporate and Other | WarnerMedia | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues		0
Eliminations and consolidations
Disaggregation of Revenue [Line Items]
Total operating revenues	(1,288)	(1,300)	(3,709)	(3,878)
Eliminations and consolidations | Wireless
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Eliminations and consolidations | Advanced Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Eliminations and consolidations | Legacy Voice & Data
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Eliminations and consolidations | Subscription
Disaggregation of Revenue [Line Items]
Total operating revenues	(790)	(798)	(2,349)	(2,475)
Eliminations and consolidations | Content
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Eliminations and consolidations | Advertising
Disaggregation of Revenue [Line Items]
Total operating revenues	(408)	(421)	(1,115)	(1,170)
Eliminations and consolidations | Other
Disaggregation of Revenue [Line Items]
Total operating revenues	(90)	(81)	(245)	(233)
Eliminations and consolidations | Equipment
Disaggregation of Revenue [Line Items]
Total operating revenues	0	0	0	0
Eliminations and consolidations | Mobility | HBO Max customer subscriptions at Mobility
Disaggregation of Revenue [Line Items]
Total operating revenues	(120)		(150)
Eliminations and consolidations | Entertainment Group | Turner channel distribution arrangements with Entertainment Group
Disaggregation of Revenue [Line Items]
Total operating revenues	(370)	(430)	(1,170)	(1,340)
Eliminations and consolidations | Entertainment Group | HBO linear channel distribution arrangements with Entertainment Group
Disaggregation of Revenue [Line Items]
Total operating revenues	$ (250)	$ (330)	$ (880)	$ (1,000)