INVESTMENTS AND FAIR VALUE MEASUREMENTS - AMORTIZED COST (Details) - USD ($) $ in Thousands	Oct. 31, 2024	Apr. 30, 2024
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	$ 115,672	$ 137,646
Unrealized Gains	4,234	7,632
Unrealized Losses	(3,750)	(5,885)
Fair Value	116,156	139,393
Marketable Equity Securities | Equity securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	45,339	50,645
Unrealized Gains	2,802	5,656
Unrealized Losses	(3,728)	(5,805)
Fair Value	44,413	50,496
Marketable Debt Securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	70,333	87,001
Unrealized Gains	1,432	1,976
Unrealized Losses	(22)	(80)
Fair Value	71,743	88,897
Marketable Debt Securities | U.S. treasury securities
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	49,749	61,306
Unrealized Gains	748	825
Unrealized Losses	0	(32)
Fair Value	50,497	62,099
Marketable Debt Securities | Corporate bonds
Debt and Equity Securities, FV-NI
Cost or Amortized Cost	20,584	25,695
Unrealized Gains	684	1,151
Unrealized Losses	(22)	(48)
Fair Value	$ 21,246	$ 26,798