Note 11 - Information as to Employee Stock Purchase, Savings, and Similar Plans (Details Textual) - USD ($)	3 Months Ended			9 Months Ended
	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay		100.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent		3.00%
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 21,579		$ 22,571	$ 76,995	$ 69,227