XML 19 R42.htm IDEA: XBRL DOCUMENT v3.3.0.814
Stock-Based Compensation (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation     $ 4,900,898 $ 4,548,445
Total unrecognized compensation cost related to unvested stock options $ 8,200,000   $ 8,200,000  
Period over which total unrecognized compensation cost related to unvested stock options will be recognized     2 years  
Weighted average grant date fair value ($ per share) $ 4.59 $ 6.51 $ 4.62 $ 9.32
Restricted Stock Units (RSUs) [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total unrecognized compensation cost related to unvested stock options $ 1,400,000   $ 1,400,000  
Period over which total unrecognized compensation cost related to unvested stock options will be recognized     2 years 4 months  
Weighted average grant date fair value ($ per share) for restricted stock units     $ 7.76  
Employees and Directors [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation $ 1,100,000 $ 708,000 $ 4,600,000 $ 4,000,000
Employees and Directors [Member] | Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Risk-free interest rate 1.05% 0.93% 0.99% 1.49%
Expected volatility 75.00% 79.00% 74.00% 110.00%
Expected life in years 5 years 5 years 5 years 5 years 1 month
Dividend yield 0.00% 0.00% 0.00% 0.00%
Forfeiture rate 7.00% 8.00% 7.00% 8.00%
Non Employee [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation $ 3,000 $ 88,000 $ 273,000 $ 547,000
Research and Development Expense [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share-based compensation expense 565,000 410,000 2,600,000 2,400,000
General and Administrative Expense [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share-based compensation expense $ 559,000 $ 298,000 $ 2,000,000 $ 1,600,000