Note G - Stock Based Compensation (Details Textual) - 2016 Restricted Stock Plan [Member] - USD ($)	9 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Sep. 01, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)			500,000
Restricted Stock [Member]
Share-based Payment Arrangement, Expense	$ 376,363	$ 249,708
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 1,014,541
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 292 days

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Number of shares authorized for issuance under share-based payment arrangement.

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