Note 3 - Cash, Cash Equivalents, and Investments - Maturity Date of CDs (Details) - USD ($)	Jun. 30, 2021	Sep. 30, 2020
Less than one year	$ 10,864,831	$ 10,582,527
1-5 years	26,721,221	25,143,000
Total	$ 37,586,052	$ 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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