Fair Value Measurements and Investments - Schedule of Debt Securities Classified by Contractual Maturity Date (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Sep. 30, 2025 |
|---|---|---|
| Fair Value Disclosures [Abstract] | ||
| Due within one year | $ 1,243 | |
| Due after one year through five years | 150 | |
| Total | $ 1,393 | $ 2,421 |
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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