7. EQUITY COMPENSATION PLANS (Details Narrative) $ / shares in Units, $ in Thousands	9 Months Ended
Jan. 31, 2019 USD ($) $ / shares shares
Stock Incentive Plans [Member]
Shares available for grant	7,294,508
Options and Restricted Stock Units [Member]
Shares available for grant	3,507,748
Future grants of share-based awards [Member]
Shares available for grant	3,786,760
Restricted Stock Units RSUs [Member]
Restricted Stock Units granted	217,200
Restricted Stock Units RSUs [Member] \| Employees [Member]
Restricted Stock Units granted	217,200
Aggregate grant date fair value \| $	$ 929
ESPP [Member]
Shares authorized under plan	2,142,857
Shares available for grant	1,231,699
Common stock purchased under plan	39,710
Stock purchase price \| $ / shares	$ 2.87
Non-Vested Employee Stock Options [Member]
Unrecognized compensation cost \| $	$ 4,287
Unrecognized cost amortization period	2 years 10 months 14 days
Non-Vested Restricted Stock Units [Member]
Unrecognized compensation cost \| $	$ 807
Unrecognized cost amortization period	3 years 7 months 2 days

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares of capital stock issued (purchased by employees) in connection with an employee stock ownership plan.

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