v2.4.0.6
Summary of Significant Accounting Policies - Additional Information (Detail) (Employees, Directors and Consultants)
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Employees, Directors and Consultants
   
Significant Accounting Policies [Line Items]    
Options granted to purchase common stock, shares 1,400,000 330,000