Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Tables)

v3.7.0.1
Stock-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2017
Stock-Based Compensation [Abstract]  
Stock-Based Compensation Expense
The following table sets forth the stock-based compensation expense that we recognized for the periods indicated (in thousands):
 
   
Three Months Ended
June 30,
   
Six Months Ended
June 30,
 
   
2017
   
2016
   
2017
   
2016
 
Stock-based compensation expense relating to:
                       
Employee and director stock options
 
$
10,723
   
$
8,154
   
$
21,858
   
$
15,435
 
Employee stock purchases
   
245
     
263
     
477
     
498
 
Total stock-based compensation expense
 
$
10,968
   
$
8,417
   
$
22,335
   
$
15,933
 
                                 
Stock-based compensation expense relating to:
                               
Cost of revenues
 
$
445
   
$
450
   
$
993
   
$
875
 
Sales and marketing
   
1,975
     
1,857
     
4,282
     
3,588
 
Research and development
   
2,221
     
1,425
     
4,717
     
2,780
 
General and administrative
   
6,327
     
4,685
     
12,343
     
8,690
 
Total stock-based compensation expense
 
$
10,968
   
$
8,417
   
$
22,335
   
$
15,933
 
Weighted Average Assumptions Used in Black-Scholes Valuation Model
The following are the weighted average assumptions used in the Black-Scholes valuation model for the periods indicated:
 
   
Three Months Ended
June 30,
   
Six Months Ended
June 30,
 
   
2017
   
2016
   
2017
   
2016
 
Expected dividend yield
   
     
     
     
 
Risk-free interest rate
   
1.5
%
   
1.0
%
   
1.5
%
   
1.0
%
Expected volatility
   
46.1
%
   
48.6
%
   
46.4
%
   
48.4
%
Expected life (in years)
   
3.4
     
3.4
     
3.4
     
3.4
 
Forfeiture rate
   
     
6.0
%
   
     
6.0
%