Note 11 - Other Operating Income (Expense), Net - Schedule of Other Operating Expenses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 30, 2026	Apr. 30, 2025	Apr. 30, 2026	Apr. 30, 2025
Total other operating income (expense)	$ 180	$ (175)	$ (67)	$ (403)
Segment Reporting, Reconciling Item, Corporate Nonsegment [Member]
Straight Path Communications Inc. class action legal fees	209	0	(978)	(7)
Straight Path Communications Inc. class action insurance claims	0	0	1,237	0
Operating Segments [Member] \| National Retail Solutions [Member]
Straight Path Communications Inc. class action legal fees	0	0	(176)	0
Operating Segments [Member] \| Net2phone [Member]
Write-off of equipment	(30)	(212)	(174)	(400)
Operating Segments [Member] \| Traditional Communications [Member]
Traditional Communications	$ 1	$ 37	$ 24	$ 4

Amount of impairment loss for long-lived asset held and used. Includes, but is not limited to, impairment loss for long-lived asset to be disposed of other than by sale.

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