Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity (Deficiency) (Schedule of Assumptions Used to Value Stock Options) (Details)

v2.4.0.8
Stockholders' Equity (Deficiency) (Schedule of Assumptions Used to Value Stock Options) (Details) (Stock Incentive Plan and Stock Option Grants to Employees and Directors [Member])
4 Months Ended 12 Months Ended
Apr. 30, 2013
Apr. 30, 2014
Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (years)   3 years 3 months 18 days  
Expected volatility   45.00%  
Expected volatility, minimum 46.30%   44.20%
Expected volatility, maximum 46.50%   50.90%
Weighted-average volatility 46.50% 45.00% 49.00%
Risk-free interest rate   0.38%  
Risk-free interest rate, minimum 0.36%   0.31%
Risk-free interest rate, maximum 0.44%   0.60%
Dividend yield 0.00% 0.00% 0.00%
Expected forfeiture rate 3.90%    1.70%
Minimum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (years) 3 years 6 months   2 years 6 months
Maximum [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (years) 3 years 9 months   3 years 9 months 18 days