Note 7 - Federal, State and Local Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Apr. 30, 2024	Apr. 30, 2023
Deferred tax liability	$ 12,893	$ 13,129
Domestic Tax Jurisdiction [Member]
Deferred gain on deconsolidation of EAM	10,669	10,669
Deferred non-cash post-employment compensation	(372)	(372)
Depreciation and amortization	73	59
Unrealized gain on securities held for sale	916	919
Right of Use Asset	(128)	(174)
Deferred charges	(138)	(136)
Other	(424)	(333)
Deferred tax liability	10,596	10,632
Unrealized gain on securities held for sale	(916)	(919)
State and Local Jurisdiction [Member]
Deferred gain on deconsolidation of EAM	2,073	2,062
Deferred non-cash post-employment compensation	(72)	(72)
Depreciation and amortization	13	125
Unrealized gain on securities held for sale	(178)	(178)
Other	105	204
Deferred tax liability	2,297	2,497
Unrealized gain on securities held for sale	$ 178	$ 178