Note 7 - Stock-based Compensation (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Payment Arrangement, Expense	$ 48,360	$ 93,360	$ 48,360	$ 93,360
Non-employee Director Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			1,000	1,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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