v3.8.0.1
Net Loss Per Common Share (Tables)
12 Months Ended
Dec. 31, 2017
Earnings Per Share [Abstract]  
Historical Outstanding Anti-Dilutive Securities
 
Years Ended December 31,
 
2017

2016
 
2015
Options outstanding to purchase common stock
0.4

 
0.7

 
1.3

Unvested restricted stock units
2.7

 
3.7

 
4.1

Senior convertible notes
4.0

 

 

Total
7.1

 
4.4

 
5.4