Stock Based Compensation (Summary Of Stock Option Activity) (Details) (USD $)	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013
Stock Based Compensation [Abstract]
Shares, Outstanding at April 30, 2013	1,814,599
Shares, Granted	316,000
Shares, Exercised
Shares, Cancelled/expired	(875,970)
Shares, Outstanding at April 30, 2014	1,254,629	1,814,599
Shares, Vested or expected to vest at April 30, 2014	1,169,962
Shares, Exercisable at April 30, 2014	828,291
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	$ 2.88
Weighted average exercise price, Outstanding at April 30, 2014	$ 2.38	$ 2.83
Weighted average exercise price, Vested or expected to vest at April 30, 2014	$ 2.46
Weighted average exercise price, Exercisable at April 30, 2014	$ 2.94
Weighted average remaining contractual term (in years), Outstanding	6 years 9 months 26 days	6 years 11 months 1 day
Weighted average remaining contractual term (in years), Vested or expected to vest at April 30, 2014	6 years 8 months 1 day
Weighted average remaining contractual term (in years), Exercisable at April 30, 2014	5 years 9 months 7 days
Aggregate intrinsic value, Outstanding	$ 41,972	$ 15,551
Aggregate intrinsic value, Vested or expected to vest at April 30, 2014	34,031
Aggregate intrinsic value, Exercisable at April 30, 2014	$ 2,268