Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Details)

v2.4.0.6
Stock-based Compensation (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
 3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Stock-based awards weighted average assumptions [Abstract]    
Dividend yield (in hundredths) 0.00% 0.00%
Expected volatility (in hundredths) 92.00% 92.00%
Risk free interest rate (in hundredths) 0.78% 1.05%
Expected term 5 years 7 months 6 days 5 years 7 months 6 days
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock-based compensation expense $ 1,619 $ 674
Research and Development [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock-based compensation expense 997 385
Selling, General and Administrative Expenses [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock-based compensation expense 622 289
Stock Options [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 4 years  
Stock option activity [Roll Forward]    
Options outstanding beginning of period (in shares) 6,788,383  
Granted (in shares) 994,053  
Exercised (in shares) (19,090)  
Forfeited, expired or cancelled (in shares) (54,930)  
Options outstanding end of period (in shares) 7,708,416  
Options exercisable at end period (in shares) 4,473,529  
Stock options activity, weighted average exercise price [Roll Forward]    
Options outstanding, beginning of period (in dollars per share) $ 8.99  
Granted (in dollars per share) $ 2.92  
Exercised (in dollars per share) $ 1.97  
Forfeited, expired or cancelled (in dollars per share) $ 31.12  
Options outstanding, end of period (in dollars per share) $ 8.07  
Options exercisable weighted average exercise price (in dollars per share) $ 11.70  
Additional Disclosures [Abstract]    
Options outstanding weighted average remaining contractual term beginning of period 7 years 4 months 10 days  
Options outstanding weighted average remaining contractual term end of period 7 years 4 months 10 days  
Options exercisable weighted average remaining contractual term 6 years 4 months 20 days  
Options outstanding, aggregate intrinsic value at beginning of period 1,531  
Options outstanding, aggregate intrinsic value at end of period 4,502  
Options exercisable, aggregate intrinsic value $ 2,245  
Restricted Stock Units (RSUs) [Member]
    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period 3 years  
Unvested RSU activity [Roll Forward]    
Unvested balance beginning of period (in shares) 1,459,853  
Granted (in shares) 895,860  
Vested (in shares) (164,998)  
Forfeited (in shares) (4,835)  
Unvested balance end of period (in shares) 2,185,880  
Unvested RSU activity, weighted average grant date fair value [Roll Forward]    
Unvested balance, beginning of period (in dollars per share) $ 2.75  
Granted (in dollars per share) $ 2.87  
Vested (in dollars per share) $ 2.50  
Forfeited (in dollars per share) $ 2.06  
Unvested balance, end of period (in dollars per share) $ 2.65  
Long Term Incentive Plan [Member] | Stock Options [Member]
    
Stock option activity [Roll Forward]    
Granted (in shares) 994,053