Note 10 - Other Comprehensive Income (Loss) - Schedule of Other Comprehensive Income and Loss (Details) - USD ($)	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Unrealized losses	$ (836,071)	$ (43,947)
Unrealized losses	215,205	11,311
Unrealized losses	(620,866)	(32,636)
Transfer of realized gains to interest expense	(545,183)	(290,779)
Transfer of realized gains to interest expense	140,329	(74,845)
Transfer of realized gains to interest expense	(404,854)	(215,934)
Net interest rate swaps	(1,381,254)	246,832
Net interest rate swaps	355,534	(63,534)
Net interest rate swaps	(1,025,720)	183,298
Amortization of actuarial losses	16,015	19,703
Amortization of actuarial losses	(4,122)	(5,072)
Amortization of actuarial losses	11,893	14,631
Other comprehensive loss	(1,365,239)	(227,129)
Other comprehensive loss	351,412	58,462
Other comprehensive loss	1,013,827	168,667
Unrealized gains (losses)	836,071	43,947
Unrealized gains (losses)	(215,205)	(11,311)
Unrealized gains (losses)	620,866	32,636
Transfer of realized gains to interest expense	(140,329)	74,845
Net interest rate swaps	1,381,254	(246,832)
Net interest rate swaps	(355,534)	63,534
Net interest rate swaps	$ 1,025,720	$ (183,298)

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