Stock Compensation Information (Summary Of Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended		12 Months Ended
	Jan. 31, 2014		Apr. 30, 2013
Stock Compensation Information [Abstract]
Shares, Outstanding at April 30, 2013	1,814,559
Shares, Granted	316,000
Shares, Exercised
Shares, Cancelled/expired	(725,200)
Shares, Outstanding at January 31, 2014	1,405,359		1,814,559
Weighted average exercise price, Outstanding at April 30, 2013	$ 2.83
Weighted average exercise price, Granted	$ 1.19
Weighted average exercise price, Exercised
Weighted average exercise price, Canceled/expired	$ 2.69
Weighted average exercise price, Outstanding at January 31, 2014	$ 2.53		$ 2.83
Weighted average remaining contractual term (in years), Outstanding at January 31, 2014	6 years 9 months 26 days		6 years 11 months 1 day
Aggregate intrinsic value, Outstanding at April 30, 2013	$ 15,551	[1]
Aggregate intrinsic value, Outstanding at January 31, 2014	$ 31,412	[1]	$ 15,551	[1]

[1] Aggregate intrinsic value is defined as the difference between the current market value and the exercise price and is estimated using the closing price of our common stock on the last trading day of the periods ended as of the dates indicated.