Note J - Weighted Average Shares Outstanding - Weighted Average Shares of Common Stock Outstanding (Details) - shares	12 Months Ended
	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021
Statement [Line Items]
Weighted average shares outstanding-basic (in shares)	6,371,229	6,509,673	6,628,749
Dilutive options and restricted stock (in shares)	195,667	313,808	332,826
Weighted average shares outstanding-diluted (in shares)	6,566,896	6,823,481	6,961,575
Share-Based Payment Arrangement, Option [Member]
Statement [Line Items]
Antidilutive securities (in shares)	315,625	120,000	152,500
Restricted Stock [Member]
Statement [Line Items]
Antidilutive securities (in shares)	15,231	4,784	2,479