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v3.23.2

Schedule of Investments and Unrealized Gains/Losses (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2023 | Apr. 30, 2023
Schedule of Investments [Line Items] |  |
Amortized Cost | $ 22,790 | $ 27,790
Unrealized Gains (Losses) | 104 | 158
Market Value | 22,894 | 27,948
Corporate Bonds [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 9,393 | 14,776
Unrealized Gains (Losses) | 63 | 100
Market Value | 9,456 | 14,876
Government Bonds and Notes [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 10,586 | 9,188
Unrealized Gains (Losses) | 30 | 33
Market Value | 10,616 | 9,221
Government Agency [Member] |  |
Schedule of Investments [Line Items] |  |
Amortized Cost | 2,811 | 3,826
Unrealized Gains (Losses) | 11 | 25
Market Value | $ 2,822 | $ 3,851

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