Pension and Other Postretirement Benefits (Schedule of Amounts Recognized in Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Jun. 30, 2020
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial losses	$ 409	$ 533
Prior service cost	2	3
Net amounts recognized	411	536
Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Actuarial losses	13	20
Prior service cost	0	0
Net amounts recognized	$ 13	$ 20

Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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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.

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