Note 11 - Other Comprehensive Income (Loss) - Schedule of Other Comprehensive Income and Loss (Details) - USD ($)	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Unrealized gains (losses), before tax	$ 694,177	$ (836,071)
Unrealized gains (losses), tax	(178,681)	215,205
Unrealized gains (losses), after tax	515,496	(620,866)
Transfer of realized gains to interest expense, before tax	(384,273)	(545,183)
Transfer of realized gains to interest expense, tax	98,912	140,329
Transfer of realized gains to interest expense, after tax	(285,361)	(404,854)
Net interest rate swaps, before tax	309,904	(1,381,254)
Net interest rate swaps, tax	(79,769)	355,534
Interest rate swaps	230,135	(1,025,720)
Amortization of net actuarial gains, before tax	(10,378)	16,015
Amortization of net actuarial gains, tax	2,671	(4,122)
Amortization of net actuarial gains, after tax	(7,707)	11,893
Other comprehensive income (loss), before tax	299,526	1,365,239
Other comprehensive income (loss), tax	(77,098)	351,412
Other comprehensive income (loss), after tax	222,428	(1,013,827)
Unrealized gains (losses), before tax	694,177	(836,071)
Amortization of net actuarial gains (losses), after tax	(7,707)	11,893
Other comprehensive income (loss), before tax	(299,526)	(1,365,239)
Other comprehensive income (loss), tax	$ (77,098)	$ 351,412

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

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