Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation and Employee Benefit Plans (Tables)

v3.8.0.1
Stock-Based Compensation and Employee Benefit Plans (Tables)
 12 Months Ended
Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
A summary of the Company’s restricted stock unit and restricted stock award activity for the year ended December 31, 2017 is as follows:
 
Number of Shares
(in thousands)
 
Weighted-Average Grant-Date Fair Value per Share
Outstanding at December 31, 2016
3,670

 
$
14.67

  Granted
1,514

 
27.11

  Assumed in acquisition
250

 
31.12

  Vested
(1,763
)
 
16.21

  Canceled
(488
)
 
20.36

Outstanding at December 31, 2017
3,183

 
20.13

Stock-Based Compensation
Stock-based compensation expense is classified in the consolidated statements of operations based on the department to which the related employee reports. The Company recognized stock-based compensation in the statements of operations as follows:
 
Years Ended December 31,
 
2017
 
2016
 
2015
 
(in thousands)
Cost of net revenue
$
332

 
$
210

 
$
213

Research and development
16,190

 
14,403

 
13,205

Selling, general and administrative
11,016

 
7,152

 
5,850

Restructuring expense
5,130

 
—

 
—

 
$
32,668

 
$
21,765

 
$
19,268

Fair Value of Employee Stock Purchase Rights
The fair values of employee stock purchase rights were estimated at their respective grant date using the following assumptions:
 
Years Ended December 31,
 
2017
 
2016
 
2015
Weighted-average grant date fair value per share
$6.20 - $7.46

 
$5.85 - $6.20

 
$2.25 - $5.02

Risk-free interest rate
0.60 - 1.39%

 
0.38 - 0.6%

 
0.09 - 0.33%

Dividend yield
—
%
 
—
%
 
—
%
Expected term (in years)
0.38 - 0.50

 
0.50

 
0.50

Volatility
29.56 - 49.94%

 
49.94 - 53.94%

 
32.65 - 59.14%

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]
A summary of the Company’s stock option activity for the year ended December 31, 2017 is as follows:
 
Number of Options
(in thousands)
 
Weighted-Average Exercise Price
 
Weighted-Average Contractual Term
(in years)
 
Aggregate Intrinsic Value
(in thousands)
Outstanding at December 31, 2016
3,025

 
$
6.78

 
 
 
 
Assumed in acquisition
1,135

 
17.44

 
 
 
 
Exercised
(835
)
 
9.42

 
 
 
 
Canceled
(255
)
 
19.50

 
 
 
 
Outstanding at December 31, 2017
3,069

 
$
8.95

 
2.58
 
$
53,686

Vested and expected to vest at December 31, 2017
3,025

 
$
8.84

 
2.54
 
$
53,243

Exercisable at December 31, 2017
2,613

 
$
7.86

 
2.17
 
$
48,548

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
The fair value of assumed stock options were estimated at the acquisition date using the following assumptions:
 
Year Ended December 31,
 
2017
Weighted-average grant date fair value per share
$
31.12

Risk-free interest rate
1.29% - 1.99%

Dividend yield
—
%
Expected term (in years)
1.6 - 6.0

Volatility
45.39% - 50.32%