Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Jan. 31, 2013	Apr. 30, 2012
Condensed Consolidated Balance Sheets [Abstract]
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	0	0
Common stock, par value
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	14,629,015	14,395,273
Common stock, shares outstanding	14,629,015	14,395,273