Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended				3 Months Ended			9 Months Ended	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Oct. 31, 2009	Jan. 31, 2013	Apr. 30, 2013 Maximum [Member]	Apr. 30, 2013 Minimum [Member]	Apr. 30, 2013 Restricted Stock Units (RSUs) [Member]	Oct. 12, 2012 Restricted Stock Units (RSUs) [Member]	Apr. 30, 2013 Restricted Stock Units (RSUs) [Member] Minimum [Member]	Apr. 30, 2013 Performance Shares [Member]	Oct. 12, 2012 Performance Shares [Member]	Oct. 12, 2012 Performance Shares [Member] Maximum [Member]	Apr. 30, 2013 2006 Stock Incentive Plan [Member]	Oct. 12, 2012 Time Based Options [Member]	Jan. 31, 2013 Unvested performance based options [Member] Maximum [Member]	Jan. 31, 2013 Unvested performance based options [Member] Minimum [Member]
Stock Based Compensation (Textual) [Abstract]
Awards vesting period								3 years			3 years	4 years		3 years
Expiration of granted option													10 years
Restricted stock units granted							2,187,100
Cancelled, Shares							0
Number of options outstanding	9,140,137			7,799,011
Weighted average exercise price of options vested and expected to vest	$ 2.85
Common stock issued, Shares	100,000
Performance target for achievement															150.00%	50.00%
Compensation expense for awards recognized	$ 507,000	$ 484,000
Unrecognized compensation costs recognition period					3 years	2 years			3 years	3 years
Number of Options Outstanding, Granted	3,055,000
Number of Options Outstanding, Cancelled	1,585,191
Unrecognized compensation costs	3,300,000						6,100,000
Stock Based Compensation (Additional Textual) [Abstract]
Aggregate intrinsic value of options outstanding	930,000			1,091,000
Common stock exercise price	16,000
Stock expense expected to be recognized over the remaining future vesting period	$ 100,000
Offer for eligible employees and independent directors to exchange ratio under Stock Incentive Plan			one-for-one basis