Segment Information (Intersegment Details) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues [Abstract]
Total revenues	$ (44,827)	$ (38,038)
Operating Segments [Member]
Revenues [Abstract]
Total revenues	(45,916)	(38,007)
Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	858	31
Eliminations and consolidations [Member]
Revenues [Abstract]
Total revenues	1,256	302
Communications [Member] | Operating Segments [Member]
Revenues [Abstract]
Total revenues	(35,393)	(35,533)
Communications [Member] | Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	0	0
WarnerMedia [Member] | Operating Segments [Member]
Revenues [Abstract]
Total revenues	(8,379)	(112)
WarnerMedia [Member] | Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	858	31
Latin America [Member] | Operating Segments [Member]
Revenues [Abstract]
Total revenues	(1,718)	(2,025)
Latin America [Member] | Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	0	0
Xandr [Member] | Operating Segments [Member]
Revenues [Abstract]
Total revenues	(426)	(337)
Xandr [Member] | Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	0	0
Consolidations [Member]
Revenues [Abstract]
Total revenues	(167)	(333)
Consolidations [Member] | Total Intersegment Revenues [Member]
Revenues [Abstract]
Total revenues	$ 398	$ 271