Note 3 - Cash, Cash Equivalents and Investments - CD Maturity Dates (Details) - USD ($)	Jun. 30, 2018	Sep. 30, 2017
Less than one year	$ 8,486,225	$ 5,937,150
1-5 years	18,226,000	19,816,000
Total	$ 26,712,225	$ 25,753,150

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

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