Note 8 - Federal, State and Local Income Taxes - Effective Income Tax Rate Reconciliation (Details)	9 Months Ended		12 Months Ended
	Jan. 31, 2024	Jan. 31, 2023	Apr. 30, 2019
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	3.04%	3.39%
Effect of dividends received deductions	(0.24%)	(0.25%)
Other, net	0.00%	0.01%
Effective income tax rate	23.80%	24.15%