Note 2 - Investments - Schedule of Components of EAM's Investment Management Operations (Details) - USD ($) $ in Thousands		3 Months Ended
		Jul. 31, 2017	Jul. 31, 2016
Value Line’s non-voting revenues interest		$ 1,978	$ 1,787
EAM's net income (2)		2,215	6,358
EAM Trust [Member]
Investment management fees earned from the Value Line Funds, net of fee waivers		3,958	3,637
12b-1 fees and other fees, net of fee waivers		1,549	1,443
Other income		55	63
Investment management fee waivers (1)	[1]	154	94
12b-1 fee waivers (1)	[1]	235	233
Value Line’s non-voting revenues interest		1,978	1,787
EAM's net income (2)	[2]	$ 316	$ 258

[1] During fiscal 2018 and 2017 investment management fee waivers primarily related to the Value Line Core Bond Fund and the 12b-1 fee waivers related to four of the Value Line Mutual Funds.

[2] Represents EAM's net income, after giving effect to Value Line's non-voting revenues interest, but before distributions to voting profits interest holders and to the Company in respect of its 50% non-voting profits interest.