Additional Financial Information (Components of Accounts Payable, Accrued Expenses and Other Current Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accrued expenses	$ 1,010	$ 907
Program rights payable	650	485
Deferred revenue	276	152
Operating lease liabilities	92	122
Other current liabilities	185	240
Total accounts payable, accrued expenses and other current liabilities	$ 2,213	$ 1,906