XML 17 R42.htm IDEA: XBRL DOCUMENT v3.2.0.727
Stock-Based Compensation (Details) - USD ($)
3 Months Ended 6 Months Ended
Jun. 30, 2015
Jun. 30, 2014
Jun. 30, 2015
Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation     $ 3,773,134 $ 3,752,687
Total unrecognized compensation cost related to unvested stock options $ 7,300,000   $ 7,300,000  
Period over which total unrecognized compensation cost related to unvested stock options will be recognized     2 years 2 months  
Weighted average grant date fair value ($ per share) $ 5.02 $ 7.33 $ 4.62 $ 9.33
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 $ 1,600,000   $ 1,600,000  
Period over which total unrecognized compensation cost related to unvested stock options will be recognized     2 years 6 months  
Weighted average grant date fair value ($ per share) for restricted stock units $ 8.01   $ 7.76  
Employees and Directors [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation $ 1,300,000 $ 1,200,000 $ 3,500,000 $ 3,300,000
Employees and Directors [Member] | Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Risk-free interest rate 1.00% 1.68% 0.99% 1.52%
Expected volatility 75.00% 110.00% 74.00% 111.00%
Expected life in years 5 years 5 years 1 month 5 years 5 years 1 month
Dividend yield 0.00% 0.00% 0.00% 0.00%
Forfeiture rate 7.00% 8.00% 8.00% 8.00%
Non Employee [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation $ 101,000 $ 69,000 $ 270,000 $ 459,000
Research and Development Expense [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share-based compensation expense 649,000 614,000 2,000,000 2,000,000
General and Administrative Expense [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Allocated share-based compensation expense $ 612,000 $ 551,000 $ 1,500,000 $ 1,300,000