Note 2 - Stock Incentive Plans and Other Share-based Compensation (Details Textual) - USD ($)	3 Months Ended	6 Months Ended
Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2023	Apr. 30, 2022
Restricted Stock [Member]
Share-Based Payment Arrangement, Shares Withheld for Tax Withholding Obligation			28,073
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 2 months 12 days
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 730,000		$ 730,000
Plan 2017 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	384,000		384,000
Plan 2017 [Member] \| Employees, Consultant and Non-employee Directors [Member]
Share-Based Payment Arrangement, Expense	$ 154,639	$ 113,212	$ 289,680	$ 237,651

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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No definition available.

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