Note G - Stock Based Compensation (Details Textual) - 2016 Restricted Stock Plan [Member] - USD ($)	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020	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	$ 121,704	$ 110,813
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 744,296
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	140,375

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

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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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