Other Comprehensive Income (Loss) (Details) - Schedule of Accumulated Other Comprehensive Income (Loss) - USD ($) $ in Thousands		12 Months Ended
		Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2020
Schedule of Accumulated Other Comprehensive Income (Loss) [Abstract]
Balance, Change in Market Value of Marketable Securities		$ (440)	$ 291	$ 490
Items of other comprehensive income (loss) before reclassification, pretax		(725)	(171)
Tax effect		(1)	(6)
Items of other comprehensive income (loss) before reclassification, net of taxes		(726)	(177)
Reclassification adjustments, pretax **	[1]	(6)	(28)
Tax effect		1	6
Tax effect		(5)	(22)
Total other comprehensive income (loss), net of taxes		$ (731)	$ (199)

[1] The reclassification adjustments represent net realized gains on the sale or redemption of available-for-sale marketable securities that were reclassified from AOCI to Other income (expense), net.