Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Number of shares authorized for issuance under share-based payment arrangement.

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Stock-Based Compensation Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Stock-Based Compensation Narrative (Details) - USD ($)	Apr. 30, 2022	Apr. 30, 2021	Apr. 30, 2022	Apr. 30, 2021
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares			122,000
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number Authorized (shares)	1,219,500		1,219,500
Number Available (shares)	249,969		249,969
2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Expense	$ 814,000	$ 559,000	$ 2,267,000	$ 1,849,000
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	15,000	5,000