Fair Value Measurements and Investments - Schedule of Non-Marketable Equity Securities (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Dec. 31, 2024 |
Dec. 31, 2023 |
Sep. 30, 2024 |
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| Fair Value Disclosures [Abstract] | |||
| Initial cost basis | $ 711 | $ 711 | |
| Adjustments: | |||
| Upward adjustments | 909 | 910 | |
| Downward adjustments, including impairment | (552) | (465) | |
| Carrying amount | 1,068 | $ 1,156 | |
| Upward adjustments | 0 | $ 9 | |
| Downward adjustments, including impairment | $ (91) | $ 0 | |
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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 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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- 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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- References No definition available.
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- Definition Equity Securities Without Readily Determinable Fair Value, Adjustments No definition available.
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- Definition Equity Securities Without Readily Determinable Fair Value, Impairment And Downward Price Adjustment, Annual Amount No definition available.
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- Definition Equity Securities Without Readily Determinable Fair Value Impairment And Downward Price Adjustment, Cumulative Amount No definition available.
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- Definition Equity Securities Without Readily Determinable Fair Value, Initial Cost No definition available.
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