Reportable Segments (Revenues) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 6,116	$ 6,698	$ 19,060	$ 20,941
Operating Segments [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	2,354	2,454	7,588	8,798
Operating Segments [Member] | Cable Networks [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	3,061	3,283	9,151	9,361
Operating Segments [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	590	851	2,048	2,458
Operating Segments [Member] | Publishing [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	279	217	649	599
Corporate and Eliminations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	(168)	(107)	(376)	(275)
Intersegment Eliminations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	(168)	(113)	(376)	(295)
Intersegment Eliminations [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	(67)	(69)	(185)	(163)
Intersegment Eliminations [Member] | Cable Networks [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	(57)	(11)	(75)	(38)
Intersegment Eliminations [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	(44)	(33)	(116)	(94)
Advertising [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	2,188	2,333	6,606	8,044
Advertising [Member] | Operating Segments [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	1,053	1,063	3,385	4,339
Advertising [Member] | Operating Segments [Member] | Cable Networks [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	1,135	1,280	3,244	3,742
Affiliate [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	2,365	2,149	6,756	6,469
Affiliate [Member] | Operating Segments [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	803	641	2,288	1,868
Affiliate [Member] | Operating Segments [Member] | Cable Networks [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	1,562	1,508	4,468	4,601
Content Licensing [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	1,221	1,828	4,717	5,202
Content Licensing [Member] | Operating Segments [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	455	695	1,796	2,442
Content Licensing [Member] | Operating Segments [Member] | Cable Networks [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	364	495	1,439	1,018
Other [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	57	77	156	209
Other [Member] | Operating Segments [Member] | TV Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	43	55	119	149
Other [Member] | Operating Segments [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	16	29	45	82
Theatrical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	6	94	176	418
Theatrical [Member] | Operating Segments [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	6	94	176	418
Home Entertainment [Member] | Operating Segments [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	150	153	533	468
Licensing [Member] | Operating Segments [Member] | Filmed Entertainment [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 418	$ 575	$ 1,294	$ 1,490