Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands		Apr. 30, 2024	Jul. 31, 2023
Debt Securities, Available-for-Sale, Amortized Cost		$ 29,952	$ 43,059
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(568)	(645)
Debt Securities, Available-for-Sale		29,384	42,414
US Treasury Bill Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		23,710	31,186
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(131)	(148)
Debt Securities, Available-for-Sale		23,579	31,038
US Government-sponsored Enterprises Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		2,378	3,881
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(6)	(8)
Debt Securities, Available-for-Sale		2,372	3,873
Corporate Bond Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		3,864	3,912
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(431)	(485)
Debt Securities, Available-for-Sale		$ 3,433	3,427
Certificates of Deposit [Member]
Debt Securities, Available-for-Sale, Amortized Cost	[1]		4,080
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax	[1]
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	[1]		(4)
Debt Securities, Available-for-Sale	[1]		$ 4,076

[1] Each of the Company’s certificates of deposit has a CUSIP, was purchased in the secondary market through a broker and may be sold in the secondary market.