Share-Based Compensation (Schedule of Additional Data Related to Stock Options) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net proceeds/(withholding) from share-based compensation	$ 8	$ 8	$ (14)
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of outstanding options at period end	11	12	10
Aggregate intrinsic value of exercisable options at period end	11	12	10
Aggregate intrinsic value of exercised options	10	8	1
Net proceeds/(withholding) from share-based compensation	32	26	3
Excess tax benefits from share based compensation	(5)	6	7
Total compensation cost, net of estimated forfeitures, related to unvested stock options not yet recognized, pre-tax	0	1	5
Total fair value of shares vested during the year	$ 3	$ 8	$ 20
Weighted-average grant date fair value per stock option (in usd per share)	$ 12.94	$ 8.26	$ 8.34
Award vesting period (in years)	3 years
Exercisable period of plans (in years)	10 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period of plans (in years)	10 years

The instrument's contractual term.

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The net cash inflow/(outflow) associated with the amount received from holders exercising their stock options and paid by the company to satisfy an employee's income tax withholding obligation when shares are withheld from settlement of a share-based award to cover taxes. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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