Schedule of Continuous Unrealized Loss Position for 12 Months or Longer (Details) - USD ($) $ in Thousands	Jul. 31, 2023	Jul. 31, 2022
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	$ 570	$ 306
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	4,115	2,623
US Treasury Bill Securities [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	86	72
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	816	892
Corporate Bond Securities [Member]
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	484	234
Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, 12 Months or Longer	$ 3,299	$ 1,731