CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Apr. 30, 2013	Apr. 30, 2012
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 936	$ 921
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, Authorized shares	10,000,000	10,000,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, Authorized shares	100,000,000	100,000,000
Common stock, Issued shares	22,614,315	22,243,903
Common stock, outstanding shares	22,614,315	22,243,903