Earnings Per Share And Stockholders' Equity (Computation Of Basic And Diluted Earnings Per Share) (Details) - USD ($)	3 Months Ended				6 Months Ended
	Oct. 31, 2022	Jul. 31, 2022	Oct. 31, 2021	Jul. 31, 2021	Oct. 31, 2022	Oct. 31, 2021
Earnings Per Share And Stockholders' Equity [Abstract]
Net income	$ 871,872	$ 1,376,675	$ 3,150,205	$ 8,796,716	$ 2,248,547	$ 11,946,921
Weighted-average shares, Basic	6,071,288		4,313,623		6,065,098	4,294,517
Weighted-average shares, Effect of dilutive stock options	73,935		240,276		94,167	150,772
Diluted	6,145,223		4,553,899		6,159,265	4,445,289
Basic earnings per share	$ 0.14		$ 0.73		$ 0.37	$ 2.78
Diluted earnings per share	$ 0.14		$ 0.69		$ 0.37	$ 2.69