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

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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 ($)	3 Months Ended		6 Months Ended
Stock-Based Compensation Narrative (Details) - USD ($)	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2022	Jan. 31, 2021
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares			107,000
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number Authorized (shares)	1,219,500		1,219,500
Number Available (shares)	260,356		260,356
2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Expense	$ 817,000	$ 506,000	$ 1,453,000	$ 1,290,000
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	32,000	18,000