Schedule of Available-for-sale Securities (Details) - USD ($) $ in Thousands		Jul. 31, 2023	Jul. 31, 2022
Debt Securities, Available-for-Sale, Amortized Cost		$ 43,059	$ 22,849
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax			1
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(645)	(547)
Debt Securities, Available-for-Sale		42,414	22,303
Certificates of Deposit [Member]
Debt Securities, Available-for-Sale, Amortized Cost	[1]	4,080	2,000
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)	(14)
Debt Securities, Available-for-Sale	[1]	4,076	1,986
US Treasury Bill Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		31,186	13,848
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(148)	(114)
Debt Securities, Available-for-Sale		31,038	13,734
US Government-sponsored Enterprises Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		3,881
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(8)
Debt Securities, Available-for-Sale		3,873
Corporate Bond Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost		3,912	3,966
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax			1
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax		(485)	(416)
Debt Securities, Available-for-Sale		$ 3,427	3,551
Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Amortized Cost			3,035
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax			(3)
Debt Securities, Available-for-Sale			$ 3,032

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