Note I - Stock-based Compensation - Stock Option Plan Comparison (Details)	3 Months Ended
Jul. 31, 2023 shares
Minimum exercise price as a percentage of fair market value at date of grant	100.00%
Last expiration date for outstanding options	May 01, 2033
Shares available for grant at July 31, 2022 (in shares)	225,000

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Period Type:	instant