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Note 2 - Summary of Significant Accounting Policies - Summary of Investments (Details) - USD ($) | Sep. 30, 2024 | Sep. 30, 2023
--- | --- | ---
Aggregate fair value | $ 358,691,000 | $ 303,128,000
Common Stock [Member] |  |
Aggregate fair value | 358,691,000 | 303,128,000
Amortized/ Adjusted cost basis | 139,094,000 | 165,412,000
Pretax unrealized gains | $ 219,597,000 | $ 137,716,000

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