Revenues (Disaggregation of Revenue) (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]
Revenues	$ 6,116	$ 6,698	$ 19,060	$ 20,941
Advertising [Member]
Disaggregation of Revenue [Line Items]
Revenues	2,188	2,333	6,606	8,044
Affiliate [Member]
Disaggregation of Revenue [Line Items]
Revenues	2,365	2,149	6,756	6,469
Content Licensing [Member]
Disaggregation of Revenue [Line Items]
Revenues	1,221	1,828	4,717	5,202
Theatrical [Member]
Disaggregation of Revenue [Line Items]
Revenues	6	94	176	418
Publishing [Member]
Disaggregation of Revenue [Line Items]
Revenues	279	217	649	599
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 57	$ 77	$ 156	$ 209