Net Recognized Gains (Losses) on Equity Investments (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Schedule Of Gain Loss On Investments Including Marketable Securities And Investments Held At Cost Income Statement Reported Amounts Summary [Line Items]
Net realized gains (losses) on investments sold	$ (8)	$ (31)	$ 57	$ 14
Net unrealized gains on investments still held	25	286	437	163
Total	(860)	69	(397)	(38)
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	(853)	(179)	(872)	(179)
Total	$ (836)	$ 76	$ (378)	$ (2)