CONSOLIDATED STATEMENT OF CHANGES IN STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Accumulated Deficit
Balance (in shares) at Apr. 30, 2021		13,414,066
Balance (in shares) at Apr. 30, 2021
Balance at Apr. 30, 2021	$ 7,428	$ 13		$ 79,945	$ (72,530)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	912			912
Issuance of common stock on exercise of stock options and warrants (in shares)		108,375
Issuance of common stock on exercise of stock options	208	$ 1		207
Net income (loss)	$ 548				548
Balance (in shares) at Apr. 30, 2022	13,522,441	13,522,441
Balance (in shares) at Apr. 30, 2022			0
Balance at Apr. 30, 2022	$ 9,096	$ 14	$ 0	81,064	(71,982)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation expense	864			864
Issuance of common stock on exercise of stock options and warrants (in shares)		36,209
Issuance of common stock on exercise of stock options	$ 85	$ 0		85
Repurchase of common stock (in shares)	(14,422)		(14,422)
Repurchase of common stock	$ (74)		$ (74)
Net income (loss)	$ (5,335)				(5,335)
Balance (in shares) at Apr. 30, 2023	13,544,228	13,544,228
Balance (in shares) at Apr. 30, 2023			14,422
Balance at Apr. 30, 2023	$ 4,636	$ 14	$ (74)	$ 82,013	$ (77,317)