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Stock-Based Compensation Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jan. 31, 2024	Jan. 31, 2023	Jan. 31, 2024	Jan. 31, 2023
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares			195,000
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number Authorized (shares)	1,719,500		1,719,500
Number Available (shares)	638,076		638,076
2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Expense	$ 1.0	$ 0.8	$ 1.8	$ 1.6
2006 Plan \| Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period (years)			1 year
2006 Plan \| Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Award Vesting Period (years)			5 years
2006 Plan \| Common Stock \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares			70,000	57,000
2006 Plan \| Common Class B \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares			125,000	0