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Investments - Schedule of Contract Maturity of Available for Sale (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Sep. 30, 2024
--- | --- | ---
Investments, Debt and Equity Securities [Abstract] |  |
Within one year | $ 474,459 | $ 578,276
After one to two years | 24,587 | 0
Total | $ 499,046 | $ 578,276

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