Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock Option Activity (Details)

v3.3.0.814
Stock-based Compensation - Stock Option Activity (Details) - Stock Options [Member]
 9 Months Ended
Sep. 30, 2015
$ / shares
shares
Stock option activity [Roll Forward]  
Outstanding beginning of period (in shares) 7,702,309
Granted (in shares) 1,790,722
Exercised (in shares) (163,663)
Forfeited, expired or cancelled (in shares) (1,156,878)
Outstanding end of period (in shares) 8,172,490
Vested and expected to vest at end of period (in shares) 7,891,195
Exercisable at end of period (in shares) 5,399,778
Stock options activity, weighted average exercise price [Roll Forward]  
Outstanding, beginning of period (in dollars per share) | $ / shares $ 8.15
Granted (in dollars per share) | $ / shares 3.79
Exercised (in dollars per share) | $ / shares 1.89
Forfeited, expired or cancelled (in dollars per share) | $ / shares 15.96
Outstanding, end of period (in dollars per share) | $ / shares 6.22
Vested and expected to vest, end of period (in dollars per share) | $ / shares 6.27
Exercisable weighted average exercise price (in dollars per share) | $ / shares $ 7.04
Additional Disclosures [Abstract]  
Outstanding, weighted average remaining contractual term end of period 6 years 6 months 15 days
Vested and expected to vest, weighted average remaining contractual term 6 years 5 months 23 days
Exercisable, weighted average remaining contractual term 5 years 8 months 16 days