Financial Instruments (Schedule of Gain/(Loss) Recognized in Earnings for Interest Rate Contracts Designated as Fair Value Hedges) (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Derivative [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest expense, net	Interest expense, net	Interest expense, net
Fair Value Hedging \| Interest Rate Swap
Derivative [Line Items]
Gain/(loss) on derivative	$ (50)	$ (44)	$ (8)
Fair Value Hedging \| Fixed-Rate Debt
Derivative [Line Items]
Gain/(loss) on derivative	$ 50	$ 44	$ 8

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

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- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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