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Financial Instruments (Other Investments) (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Investment Holdings [Line Items] |  |
Life Insurance Contracts | $ 43,773 | $ 44,808
Other Investments | 73,764 | 81,705
Equity Mutual Fund |  |
Investment Holdings [Line Items] |  |
Mutual Funds | 13,143 | 19,523
Fixed Income Mutual Fund |  |
Investment Holdings [Line Items] |  |
Mutual Funds | $ 16,848 | $ 17,374

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