Note O - Income taxes (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Expense (Benefit), Total	$ 4,314,700	$ (62,716)	$ 7,271,580	$ (340,484)
Effective Income Tax Rate Reconciliation, Percent, Total			22.90%	23.50%