Stock-Based Compensation Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Oct. 31, 2023	Oct. 31, 2022
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares	182,000
2006 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number Authorized (shares)	1,219,500
Number Available (shares)	120,805
2006 Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based Compensation Expense	$ 0.8	$ 0.8
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	57,000	40,000
2006 Plan \| Common Class B \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted, number of shares	125,000	0

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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