Note 5 - Other Comprehensive Income (Loss) (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 1,354	$ (1,898)	$ 0

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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