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Financial Instruments (Other Investments) (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Sep. 30, 2023
--- | --- | ---
Investment Holdings [Line Items] |  |
Life Insurance Contracts | $ 43,862 | $ 42,242
Other Investments | 78,744 | 73,976
Equity Mutual Fund |  |
Investment Holdings [Line Items] |  |
Mutual Funds | 18,291 | 15,837
Fixed Income Mutual Fund |  |
Investment Holdings [Line Items] |  |
Mutual Funds | $ 16,591 | $ 15,897

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