Restructuring, Programming Charges and Other Corporate Matters (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 424	$ 310	$ 258
Payments for restructuring			234	219
Other corporate matters			57	128	0
Merger-related costs			294	0	0
Settlement of commercial dispute			40
Legal proceedings			17
Programming charges	$ 589	$ 162	589	162	144
Restructuring-related costs			0	52	0
Severance costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges			401	235	224
Contract termination and other related costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 23	$ 75	$ 12