CONSOLIDATED BALANCE SHEETS [Parenthetical] (USD $)	Apr. 30, 2012	Apr. 30, 2011
Redeemable common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Redeemable common stock, shares outstanding	12,533,333	12,533,333
Preferred stock, par value (in dollars per share)	$ 10	$ 10
Preferred stock, shares authorized	56,075	56,075
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	37,740,345	36,956,667
Common stock, shares outstanding	34,529,000	33,870,000
Treasury stock, shares	3,236,000	3,236,000