Consolidated Statements of Changes In Stockholders' Equity (USD $)	Total	Preferred Stock	Common Stock	Capital in excess of par value	Retained earnings
Beginning balance at Apr. 30, 2010	$ 47,663,207	$ 0	$ 38,226	$ 19,647,360	$ 27,977,621
Stock-based compensation	9,657			9,657
Exercise of stock options	92,679		417	92,262
Net income	1,978,034				1,978,034
Ending balance at Apr. 30, 2011	49,743,577	0	38,643	19,749,279	29,955,655
Stock-based compensation	2,414			2,414
Exercise of stock options	99,656		453	99,203
Net income	1,134,324				1,134,324
Tax benefit from exercise of options	41,100			41,100
Ending balance at Apr. 30, 2012	$ 51,021,071	$ 0	$ 39,096	$ 19,891,996	$ 31,089,979