Segment Information (Summary of Revenues by Segment by Component to Consolidated) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Disaggregation Of Revenue [Line Items]
Revenues	$ 2,890	$ 3,215	$ 4,087	$ 2,717	$ 2,418	$ 3,440	$ 3,778	$ 2,667	$ 12,909	$ 12,303	$ 11,389
Operating Segments | Cable Network Programming Segment
Disaggregation Of Revenue [Line Items]
Revenues									5,683	5,492	5,381
Operating Segments | Cable Network Programming Segment | Affiliate Fee
Disaggregation Of Revenue [Line Items]
Revenues									3,995	3,870	3,804
Operating Segments | Cable Network Programming Segment | Advertising
Disaggregation Of Revenue [Line Items]
Revenues									1,337	1,164	1,184
Operating Segments | Cable Network Programming Segment | Other
Disaggregation Of Revenue [Line Items]
Revenues									351	458	393
Operating Segments | Television Segment
Disaggregation Of Revenue [Line Items]
Revenues									7,048	6,661	5,979
Operating Segments | Television Segment | Affiliate Fee
Disaggregation Of Revenue [Line Items]
Revenues									2,440	2,038	1,708
Operating Segments | Television Segment | Advertising
Disaggregation Of Revenue [Line Items]
Revenues									4,094	4,169	3,872
Operating Segments | Television Segment | Other
Disaggregation Of Revenue [Line Items]
Revenues									514	454	399
Operating Segments | Other, Corporate and Eliminations Segment
Disaggregation Of Revenue [Line Items]
Revenues									$ 178	$ 150	$ 29