Schedule of Available-for-sale Securities, Unrealized Loss Position (Details) - USD ($) $ in Thousands	Oct. 31, 2023	Jul. 31, 2023
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	$ 711	$ 645
Debt Securities, Available-for-Sale, Unrealized Loss Position	33,242	41,635
Certificates of Deposit [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	3	4
Debt Securities, Available-for-Sale, Unrealized Loss Position	1,917	3,356
US Treasury Bill Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	141	148
Debt Securities, Available-for-Sale, Unrealized Loss Position	24,944	31,038
US Government-sponsored Enterprises Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	3	8
Debt Securities, Available-for-Sale, Unrealized Loss Position	3,044	3,873
Corporate Bond Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Accumulated Loss	564	485
Debt Securities, Available-for-Sale, Unrealized Loss Position	$ 3,337	$ 3,368