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Schedule of Investments and Unrealized Gains/Losses (Details) $ in Thousands	6 Months Ended
	Oct. 31, 2022 USD ($)
Net Investment Income [Line Items]
Total Cost	$ 35,868
Unrealized Gains (Losses)	(28)
Market Value	35,840
Corporate Bonds [Member]
Net Investment Income [Line Items]
Total Cost	27,364
Unrealized Gains (Losses)	(23)
Market Value	27,341
Government Bonds and Notes [Member]
Net Investment Income [Line Items]
Total Cost	5,008
Unrealized Gains (Losses)
Market Value	5,008
Government Agency [Member]
Net Investment Income [Line Items]
Total Cost	3,496
Unrealized Gains (Losses)	(5)
Market Value	$ 3,491

X

- Definition

Cost of the investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

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