Equity-Based Compensation (Summary of Equity-Based Compensation) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity-based compensation	$ 44	$ 42	$ 75	$ 74
Intrinsic value of all settled equity-based awards	10	3	91	6
Tax benefit on settled equity-based awards	$ 2	$ 1	$ 16	$ 1

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

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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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