Fair Value Measurements and Investments - Schedule of Non-Marketable Equity Securities (Details) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Sep. 30, 2022 |
Sep. 30, 2021 |
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| Fair Value Disclosures [Abstract] | ||
| Initial cost basis | $ 734 | |
| Upward adjustments | 810 | |
| Downward adjustments (including impairment) | (349) | |
| Carrying amount, end of period | 1,195 | |
| Upward adjustments | 231 | $ 484 |
| Downward adjustments (including impairment) | $ (341) | $ (3) |
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- Definition Amount of investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of cumulative loss from downward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Equity Securities Without Readily Determinable Fair Value, Cost No definition available.
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