Equity-Based Compensation (Summary of Equity-Based Compensation) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-based compensation	$ 37	$ 41	$ 112	$ 115
Intrinsic value of all settled equity-based awards	4	2	95	8
Tax benefit on settled equity-based awards	$ 1	$ 1	$ 17	$ 2

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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