Note 3 - Cash, Cash Equivalents and Investments - Maturity Date of CDs (Details) - USD ($)	Jun. 30, 2019	Sep. 30, 2018
Less than one year	$ 14,638,219	$ 8,930,225
1-5 years	22,519,000	17,974,000
Total	$ 37,157,219	$ 26,904,225

Amount of investment in debt security measured at amortized cost (held-to-maturity).

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