Earnings Per Share - Calculations of Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Apr. 30, 2022	Apr. 30, 2021
Basic and diluted net income per share computation (dollars in thousands):
Net income attributable to common stockholders	$ 548	$ 362
Basic net income per share (in usd per share)	$ 0.04	$ 0.03
Diluted income per share computation
Net income attributable to common stockholders	$ 548	$ 362
Weighted Average common shares (in shares)	13,197,170	13,138,995
Incremental shares from assumed exercise of warrants and stock options (in shares)	962,629	1,434,566
Adjusted weighted average share - diluted (in shares)	14,159,799	14,573,561
Diluted net income per share (in usd per share)	$ 0.04	$ 0.02