Net Recognized Gains (Losses) on Equity Investments (Detail) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]
Net realized gains on investments sold	$ 123	$ 83	$ 276
Net unrealized gains on investments still held	1,057	69	479
Total	1,232	32	648
Equity Securities
Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]
Impairments of investments	(11)	(116)	(10)
Total	$ 1,169	$ 36	$ 745