v3.25.2
Note 2 - Investments (Details Textual) - USD ($)
 3 Months Ended 12 Months Ended
Jul. 31, 2025
Jul. 31, 2024
Apr. 30, 2025
Equity Securities, FV-NI, Cost $ 15,411,000   $ 15,513,000
Equity securities 22,126,000   20,879,000
Proceeds from Sale of Equity Securities, FV-NI 215,000 $ 90,000  
Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent 15,000 177,000  
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax 3,000 47,000  
Equity Securities, FV-NI, Gain (Loss) (5,000) 0  
Equity Method Investments 61,220,000   60,807,000
EAM Trust [Member]      
Fair Value of Contributed Capital at Inception 55,805,000   55,805,000
Cash and Liquid Securities in Excess of Working Capital Requirements Contributed to Capital Account 5,820,000   5,820,000
Equity Method Investment, Other-than-Temporary Impairment $ 0 0  
Percentage of Non Voting Profit Interest 50.00%    
Accrued Non Voting Revenues and Non Voting Profits Interests Payable $ 5,057,000   4,493,000
Fixed Income Securities [Member]      
Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale 2,147,000 $ 16,357,000  
AOCI, Debt Securities, Available-for-Sale, Adjustment, after Tax 65,000   83,000
Other Comprehensive Income (Loss), Available-for-Sale Securities Adjustment, Net of Tax, Portion Attributable to Parent (18,000)   (237,000)
OCI, Debt Securities, Available-for-Sale, Unrealized Holding Gain (Loss), before Adjustment, Tax $ 3,000   $ (50,000)
Debt Securities, Available-for-Sale, Weighted Average Yield 4.20%   4.30%
Fixed Income Securities [Member] | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]      
AOCI Tax, Attributable to Parent $ 14,000   $ 17,000