FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Schedule of Available-for-sale Securities Reconciliation - Fixed Income Securities [Member] - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Jan. 31, 2021	Apr. 30, 2020
FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Schedule of Available-for-sale Securities Reconciliation [Line Items]
Cost	$ 10,029	$ 10,081
Gross Unrealized Gains	492	495
Gross Unrealized Losses	(41)	(6)
Fair Market Value	$ 10,480	$ 10,570

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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