5. Equity Compensation Plans (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Oct. 31, 2019	Oct. 31, 2018
Employee Stock Purchase Plan [Member]
Stock reserved for issuance	1,148,735
Stock issued during period, ESPP	47,526
Price per share, ESPP	$ 3.94
RSUs [Member]
Unrecognized compensation cost weighted average vesting period	2 years 10 months 24 days	3 years 3 months 22 days
Unrecognized compensation cost related to non-vested RSUs	$ 4,600	$ 1,600
Stock Incentive Plans [Member]
Stock reserved for issuance	7,106,600
Stock Incentive Plans [Member] \| Options and RSU's [Member]
Stock reserved for issuance	3,906,628
Stock Incentive Plans [Member] \| Future Grants [Member]
Stock reserved for issuance	3,199,972

Aggregate number of common shares reserved for future issuance.

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