Note F - Property, Plant and Equipment (Details Textual)	3 Months Ended	6 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2021 USD ($)	May 25, 2021 USD ($) ft² a	Mar. 31, 2021 USD ($)
Construction in Progress, Gross	$ 5,994,357	$ 5,994,357		$ 9,614
Accumulated Depreciation, Depletion and Amortization, Wrote-off	115,578	2,060,226
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance	25,340,164	25,340,164		$ 30,180,893
Facility in Sinton, Texas [Member]
Area of Land (Acre) | a			26.5
Lessee, Operating Lease, Term of Contract (Year)			99 years
Capital Expenditures, Expected Cost			$ 21,000,000
Construction in Progress, Gross	5,994,357	5,994,357
Payments for Construction in Process		2,760,289
Construction in Progress Expenditures Incurred but Not yet Paid		3,234,068
Facility in Sinton, Texas [Member]
Area of Real Estate Property (Square Foot) | ft²			70,000
Decatur Facility Equipment [Member]
Proceeds from Sale of Machinery and Equipment		160,542
Property, Plant and Equipment, Gross, Ending Balance	3,604,209	3,604,209
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance	$ 3,447,465	$ 3,447,465