Shareholders' Equity (Narrative) (Details) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended			36 Months Ended
	Sep. 30, 2023 shares	Jun. 30, 2024 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) shares
Class of Stock [Line Items]
Treasury Stock, Value, Acquired, Cost Method | $		$ 759	$ 2,007	$ 1,000
Share repurchase program activity | $		750	2,000	1,000
Retained earnings decrease | $		$ 286	$ 642		$ 642
Common shares, authorized		755,000,000	755,000,000		755,000,000
Preferred shares, authorized		500,000	500,000		500,000
Common Class A
Class of Stock [Line Items]
Common shares, authorized		750,000,000	750,000,000		750,000,000
Common Stock, Voting Rights, Votes		1
Common Class B
Class of Stock [Line Items]
Common shares, authorized		5,000,000	5,000,000		5,000,000
Treasury Shares
Class of Stock [Line Items]
Treasury Stock, Value, Acquired, Cost Method | $		$ 859	$ 1,907	$ 1,000
Treasury Stock, Shares, Acquired		9,000,000.0	24,600,000	19,500,000
Share repurchase program activity | $					$ 3,800
Treasury Shares | $200 million share repurchase program [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired				3,600,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares				$ 56.02
Treasury Shares | $300 million share repurchase program [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired				6,100,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares				$ 49.39
Treasury Shares | $500 million share repurchase program [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired	900,000	5,700,000	4,600,000	9,800,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares		$ 91.15	$ 87.18	$ 51.10
Treasury Shares | $250 million share repurchase program
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired		2,400,000	3,200,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares		$ 88.22	$ 77.50
Treasury Shares | Second $250 million share repurchase program [Member]
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired			3,200,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares			$ 77.27
Treasury Shares | $1 billion share repurchase program
Class of Stock [Line Items]
Treasury Stock, Shares, Acquired			13,600,000
Treasury shares acquired, average price per share (in usd per share) | $ / shares		$ 103.67	$ 73.36