Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock Option Activity (Details)

v3.4.0.3
Stock-based Compensation - Stock Option Activity (Details) - Stock Options [Member]
3 Months Ended
Mar. 31, 2016
$ / shares
shares
Stock option activity [Roll Forward]  
Outstanding beginning of period (in shares) | shares 7,690,297
Granted (in shares) | shares 65,900
Forfeited, expired or cancelled (in shares) | shares (330,940)
Outstanding end of period (in shares) | shares 7,425,257
Vested and expected to vest at end of period (in shares) | shares 7,255,365
Exercisable at end of period (in shares) | shares 5,739,469
Stock options activity, weighted average exercise price [Roll Forward]  
Outstanding, beginning of period (in dollars per share) | $ / shares $ 6.33
Granted (in dollars per share) | $ / shares 1.04
Forfeited, expired or cancelled (in dollars per share) | $ / shares 8.71
Outstanding, end of period (in dollars per share) | $ / shares 6.18
Vested and expected to vest, end of period (in dollars per share) | $ / shares 6.21
Exercisable weighted average exercise price (in dollars per share) | $ / shares $ 6.58
Outstanding, weighted average remaining contractual term end of period 6 years 5 months 5 days
Vested and expected to vest, weighted average remaining contractual term 6 years 4 months 13 days
Exercisable, weighted average remaining contractual term 5 years 10 months 2 days