Description of Company and Basis of Presentation (Details - Statement of stockholder equity) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2023	Oct. 31, 2022	Oct. 31, 2023	Oct. 31, 2022
Beginning balance, value	$ 190,268	$ 178,796	$ 189,169	$ 174,526
Common stock issued under equity compensation plans	120	566	998	1,578
Stock-based compensation expense	2,466	2,786	4,809	4,683
Net loss	(9,521)	(520)	(11,643)	841
Ending balance, value	183,333	181,628	183,333	181,628
Previously Reported [Member]
Beginning balance, value	190,598		189,470
Common stock issued under equity compensation plans	120		998
Stock-based compensation expense	2,466		4,809
Net loss	(9,509)		(11,602)
Ending balance, value	183,675		183,675
Revision of Prior Period, Adjustment [Member]
Beginning balance, value	(330)		(301)
Common stock issued under equity compensation plans
Stock-based compensation expense
Net loss	(12)		(41)
Ending balance, value	(342)		(342)
Retained Earnings [Member]
Beginning balance, value	(433,240)	(430,016)	(431,118)	(431,377)
Common stock issued under equity compensation plans
Stock-based compensation expense
Net loss	(9,521)	(520)	(11,643)	841
Ending balance, value	(442,761)	$ (430,536)	(442,761)	$ (430,536)
Retained Earnings [Member] | Previously Reported [Member]
Beginning balance, value	(432,910)		(430,817)
Common stock issued under equity compensation plans
Stock-based compensation expense
Net loss	(9,509)		(11,602)
Ending balance, value	$ (442,419)		$ (442,419)