Marketable Securities (Details) - Schedule of Unrealized Gain (Loss) on Investments - Fixed Income Securities [Member] - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Marketable Securities (Details) - Schedule of Unrealized Gain (Loss) on Investments [Line Items]
Fair Value, Less than 12 months	$ 2,349	$ 1,793
Unrealized Losses, Less than 12 months	(146)	(52)
Fair Value, Morethan 12 months	5,573	614
Unrealized Losses, More than 12 months	(316)	(50)
Fair Value	7,922	2,407
Unrealized Losses	$ (462)	$ (102)