Segment Information (Summary of Revenues by Segment by Component to Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Disaggregation Of Revenue [Line Items]
Revenues	$ 4,087	$ 3,778	$ 6,804	$ 6,445
Operating Segments | Cable Network Programming Segment
Disaggregation Of Revenue [Line Items]
Revenues	1,488	1,469	2,813	2,754
Operating Segments | Cable Network Programming Segment | Affiliate Fee
Disaggregation Of Revenue [Line Items]
Revenues	928	957	1,901	1,896
Operating Segments | Cable Network Programming Segment | Advertising
Disaggregation Of Revenue [Line Items]
Revenues	441	337	740	591
Operating Segments | Cable Network Programming Segment | Other
Disaggregation Of Revenue [Line Items]
Revenues	119	175	172	267
Operating Segments | Television Segment
Disaggregation Of Revenue [Line Items]
Revenues	2,556	2,266	3,906	3,622
Operating Segments | Television Segment | Affiliate Fee
Disaggregation Of Revenue [Line Items]
Revenues	590	479	1,150	934
Operating Segments | Television Segment | Advertising
Disaggregation Of Revenue [Line Items]
Revenues	1,841	1,673	2,511	2,460
Operating Segments | Television Segment | Other
Disaggregation Of Revenue [Line Items]
Revenues	125	114	245	228
Operating Segments | Other, Corporate and Eliminations Segment
Disaggregation Of Revenue [Line Items]
Revenues	$ 43	$ 43	$ 85	$ 69