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Financial Instruments - Other Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Summary of Investment Holdings [Line Items] |  |
Life Insurance Contracts | $ 44,478 | $ 44,808
Total other investments | 68,346 | 81,705
Equity Mutual Fund |  |
Summary of Investment Holdings [Line Items] |  |
Mutual Funds | 13,786 | 19,523
Fixed Income Mutual Fund |  |
Summary of Investment Holdings [Line Items] |  |
Mutual Funds | $ 10,082 | $ 17,374

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