Treasury Stock and Repurchase Program (Detail Textuals) - USD ($)		1 Months Ended		12 Months Ended
		Jan. 31, 2012	Jan. 31, 2011	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013	Sep. 19, 2012
Equity, Class of Treasury Stock [Line Items]
Number of treasury shares	[1]			8,433	58,499	19,953
Total average cost	[1]			$ 122,000	$ 550,000	$ 182,000
September 2012 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount of common stock							$ 3,000,000
January 2011 Share Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Number of treasury shares			18,400
Former Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Number of treasury shares		85,219
Total average cost		$ 1,036,000

[1] Were acquired during the $3 million repurchase program authorized in September 2012.