Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Oct. 31, 2011	Apr. 30, 2011
Condensed Consolidated Balance Sheets
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 66	$ 249
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	55,000	200,000
Common stock, shares issued	26,581	26,545
Common stock, shares outstanding	26,581	26,545