Note N - Supplemental Cash Flow Information (Details Textual) - USD ($)	9 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2021
Interest Paid, Excluding Capitalized Interest, Operating Activities	$ 154,000	$ 6,000
Income Taxes Paid, Net, Total	7,487,000	$ 10,000
Proceeds from Income Tax Refunds	423,000
Construction in Progress, Gross	12,983,850		$ 9,614
Capital Expenditures Incurred but Not yet Paid	$ 5,600,000