Note 1 - Summary of Significant Accounting Policies - Maturity Date of CDs (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2020
Less than one year	$ 10,373,831	$ 10,582,527
1-5 years	36,912,777	25,143,000
Total	$ 47,286,608	$ 35,725,527

Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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