Net Recognized Gains (Losses) on Equity Investments (Detail) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Sep. 30, 2021 |
Sep. 30, 2020 |
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| 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 | $ 37 | $ 17 |
| Net unrealized gains on investments still held | 325 | 100 |
| Total | 371 | 125 |
| 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 | 0 | (9) |
| Total | $ 362 | $ 108 |
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- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of realized and unrealized gain (loss) on investment. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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. No definition available.
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- Details
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