Note K - Supplemental Cash Flow Information (Details Textual) - USD ($)	9 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Taxes Paid	$ 259,000	$ 1,846,000
Interest Paid, Excluding Capitalized Interest, Operating Activities	2,463	$ 17,545
Noncash Portion of Finance Lease Right of Use Asset	518,616
Transfer of Ownership of Life Insurance Policy to Retired Officer [Member]
Other Significant Noncash Transaction, Value of Consideration Given	$ 121,000

Amount of noncash portion of finance lease right of use asset.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The value of the noncash (or part noncash) consideration given (for example, liability, equity) in a transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of a transaction not resulting in cash receipts or cash payments in the period.

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