Related Party Transactions (Detail Textuals) (USD $)	3 Months Ended
	Jul. 31, 2013	Jul. 31, 2012	Apr. 30, 2013
Related Party Transaction [Line Items]
Receivables from affiliates	$ 2,000
Value Line Inc
Related Party Transaction [Line Items]
Reimbursed income	51,000	0
Percentage of ownership in outstanding shares of common stock of the company by parent	87.65%
Receivables from affiliates	2,000		0
Value Line Inc | Investment In EAM Trust
Related Party Transaction [Line Items]
Non voting profits interest in variable entity not yet paid	1,752,000		1,621,000
EAM Trust
Related Party Transaction [Line Items]
Total assets of value line funds managed by EAM	$ 2,200,000,000	$ 2,000,000,000
Percentage of assets increased in funds	10.50%
Percentage of non voting profits interests due each quarter from EAM	90.00%
EAM Trust | Minimum
Related Party Transaction [Line Items]
Investment management fee revenues from its mutual fund and separate accounts business	41.00%
EAM Trust | Maximum
Related Party Transaction [Line Items]
Investment management fee revenues from its mutual fund and separate accounts business	55.00%