Note 7 - Debt Securities - Schedule of Unrealized Loss Position (Details) - USD ($) $ in Thousands	Apr. 30, 2026	Jul. 31, 2025
Debt securities, unrealized loss	$ (162)	$ (227)
Debt securities, fair value	26,557	21,452
Debt securities, unrealized loss 12 months or longer	(145)	(214)
Debt securities, fair value 12 months or longer	2,799	3,296
US Treasury Bill Securities [Member]
Debt securities, unrealized loss	(15)	(27)
Debt securities, fair value	15,784	12,926
Debt securities, unrealized loss 12 months or longer	(9)	(19)
Debt securities, fair value 12 months or longer	337	329
US Government-sponsored Enterprises Debt Securities [Member]
Debt securities, unrealized loss	(10)	(4)
Debt securities, fair value	7,990	5,550
Corporate Bond Securities [Member]
Debt securities, unrealized loss	(137)	(196)
Debt securities, fair value	2,783	2,976
Debt securities, unrealized loss 12 months or longer	(136)	(195)
Debt securities, fair value 12 months or longer	$ 2,462	$ 2,967

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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