Additional Financial Information (Components of Other Non-current Assets) (Details) - USD ($) $ in Millions		Sep. 30, 2020	Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Investments	[1]	$ 755	$ 618
Operating lease ROU assets		505	539
Grantor Trust		260	247
Inventories, net		255	202
Other		165	195
Total other non-current assets		$ 1,940	$ 1,801

[1] Included investments accounted for at fair value on a recurring basis of $640 million and $531 million as of September 30, 2020 and June 30, 2020, respectively (See Note 4—Fair Value).