FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Schedule of Available-for-sale Securities Reconciliation - Fixed Income Securities [Member] - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Oct. 31, 2021	Apr. 30, 2021
FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Schedule of Available-for-sale Securities Reconciliation [Line Items]
Cost	$ 9,746	$ 10,022
Gross Unrealized Gains	313	393
Gross Unrealized Losses	(104)	(102)
Fair Market Value	$ 9,955	$ 10,313

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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