Segment Information (Reconciliation of Assets from Segments to Consolidated) (Details) - USD ($) $ in Millions		Dec. 31, 2020	Jun. 30, 2020
Segment Reporting Information [Line Items]
Total assets		$ 22,754	$ 21,750
Investments	[1]	1,006	618
Operating Segments | Cable Network Programming Segment
Segment Reporting Information [Line Items]
Total assets		2,681	2,591
Operating Segments | Television Segment
Segment Reporting Information [Line Items]
Total assets		8,140	7,054
Operating Segments | Other, Corporate and Eliminations Segment
Segment Reporting Information [Line Items]
Total assets		$ 10,927	$ 11,487

[1] Included investments accounted for at fair value on a recurring basis of $894 million and $531 million as of December 31, 2020 and June 30, 2020, respectively (See Note 4—Fair Value).