Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Summary of Stock Option Activity (Details)

v3.4.0.3
Stock-Based Compensation - Summary of Stock Option Activity (Details) - $ / shares
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]    
Stock options, Outstanding, balance 12,795,000  
Stock options, Granted 2,524,000  
Stock options, Exercised (219,000)  
Stock options, Cancelled/Forfeited (255,000)  
Stock options, Outstanding, Balance 14,845,000 12,795,000
Stock options, Options vested and exercisable 6,789,000  
Weighted-average exercise price, Outstanding, Balance $ 5.89  
Weighted-average exercise price, Granted 5.42  
Weighted-average exercise price, Exercised 2.35  
Weighted-average exercise price, Cancelled/Forfeited 8.55  
Weighted-average exercise price, Outstanding, Balance 5.82 $ 5.89
Weighted-average exercise price, Options vested and exercisable $ 4.16  
Weighted-average remaining contractual life, options outstanding 8 years 7 years 9 months 26 days
Weighted-average remaining contractual life, options vested and exercisable 6 years 9 months 7 days