Note 1 - Organization and Summary of Significant Accounting Policies (Details Textual) - USD ($) |
3 Months Ended | |
|---|---|---|
Jul. 31, 2025 |
Apr. 30, 2025 |
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| Investments, Fair Value Disclosure | $ 80,918,000 | $ 76,929,000 |
| Liabilities, Fair Value Disclosure | 0 | |
| Money Market Funds, at Carrying Value | 33,430,000 | 33,615,000 |
| Fair Value, Inputs, Level 3 [Member] | ||
| Investments, Fair Value Disclosure | $ 0 | $ 0 |
| EAM Trust [Member] | ||
| Non Voting Profits Interest Percent | 50.00% | |
| EAM Trust [Member] | Minimum [Member] | ||
| Non Voting Revenues Interest Percent | 41.00% | |
| Percentage of Non Voting Profits Interests Due from Ex Subsidiary Payable to Parent under Agreement | 90.00% | |
| EAM Trust [Member] | Maximum [Member] | ||
| Non Voting Revenues Interest Percent | 55.00% |
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Fair value of financial and nonfinancial obligations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. No definition available.
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- Definition Represents percentage of non-voting profits interest. No definition available.
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- Definition Represents percentage of non-voting revenues interest. No definition available.
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- Definition Represents the stated percentage of non voting profits interests due from ex-subsidiary payable to parent under agreement. No definition available.
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