Share-Based Compensation (Additional Data Related to Restricted Share Unit Activity) (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Restricted Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost, net of estimated forfeitures, related to nonvested restricted share and share unit awards not yet recognized, pre-tax	$ 73	$ 73	$ 73
Weighted-average period in years over which restricted share and share unit cost is expected to be recognized (in years)	2 years	2 years	2 years
Total fair value of shares vested during the year	$ 58	$ 74	$ 70
Award vesting period (in years)	3 years
Performance Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost, net of estimated forfeitures, related to nonvested restricted share and share unit awards not yet recognized, pre-tax	$ 38	$ 17	$ 26
Weighted-average period in years over which restricted share and share unit cost is expected to be recognized (in years)	2 years	2 years	2 years
Total fair value of shares vested during the year	$ 23	$ 14	$ 1