XML 46 R32.htm IDEA: XBRL DOCUMENT v3.8.0.1
STOCK PLANS AND SHARE BASED COMPENSATION (Tables)
 12 Months Ended
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Summary of stock-based compensation expense [Table Text Block]
The following table summarizes the stock-based compensation expense recognized in accordance with ASC 718-10 for the years ended December 31, 2017, 2016 and 2015:
 
Year Ended December 31,
(in thousands)
2017
 
2016
 
2015
Cost of revenues
$
1,321

 
$
1,148

 
$
933

Research and development
8,496

 
7,309

 
5,255

Sales and marketing
5,197

 
4,489

 
3,644

General and administrative
9,663

 
7,939

 
4,935

Total stock-based compensation expense
$
24,677

 
$
20,885

 
$
14,767
Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block]
The following table summarizes total compensation expense related to unvested awards not yet recognized, net of expected forfeitures, and the weighted average period over which it is expected to be recognized as of December 31, 2017:
 
Unrecognized Compensation
Expense for Unvested
Awards
(in thousands)
 
Weighted Average
Remaining Recognition
Period
(in years)
Long-term performance-based awards
$
3,519

 
1.36
Restricted stock units
35,132

 
3.73
Purchase plan
128

 
0.08
Total unrecognized compensation expense
$
38,779

 
 
Fair value assumptions for employees' stock purchase rights under the Purchase Plan [Table Text Block]
The fair value of employees’ stock purchase rights under the Purchase Plan was estimated using the Black-Scholes model with the following weighted-average assumptions used during the three years ended December 31, 2017, 2016 and 2015:
 
Year Ended December 31,
 
2017
 
2016
 
2015
Risk-free interest rates
0.91%
 
0.44%
 
0.13%
Expected volatility rates
30%
 
32%
 
29%
Expected dividend yield
0.80%
 
0.96%
 
1.08%
Expected term of purchase rights (in years)
0.50
 
0.50
 
0.50
Weighted-average estimated fair value of purchase rights
$16.74
 
$12.23
 
$10.18
Summary of option activity under the Plans [Table Text Block]
A summary of stock options outstanding as of December 31, 2017, and activity during three years then ended, is presented below:
 (shares and intrinsic value in thousands)
Shares
 
Weighted
Average
Exercise
Price
 
Weighted Average
Remaining Contractual
Term
(in years)
 
Aggregate
Intrinsic
Value
Outstanding at January 1, 2015
1,344

 
$
27.27

 
 
 
 
Granted
—

 
—

 
 
 
 
Exercised
(311
)
 
$
26.11

 
 
 
 
Forfeited or expired
(3
)
 
$
37.97

 
 
 
 
Outstanding at December 31, 2015
1,030

 
$
27.58

 
 
 
 
Granted
—

 
—

 
 
 
 
Exercised
(333
)
 
$
25.41

 
 
 
 
Forfeited or expired
—

 
—

 
 
 
 
Outstanding at December 31, 2016
697

 
$
28.62

 
 
 
 
Granted
—

 
—

 
 
 
 
Exercised
(186
)
 
$
27.48

 
 
 
 
Forfeited or expired
—

 
—

 
 
 
 
Outstanding at December 31, 2017
511

 
$
29.03

 
2.05
 
$
22,770

Vested and Exercisable at December 31, 2017
511

 
 
 
2.05
 
$
22,770
Summary of stock options outstanding by exercise price range [Table Text Block]
The following table summarizes the stock options outstanding at December 31, 2017:
 
 
Options Outstanding
 
Options Exercisable
(shares in thousands)

Range of Exercise Prices
 
Options Outstanding
 
Weighted Average
Remaining Contractual Term
(in years)
 
Weighted Average Exercise Price
 
Options Exercisable
 
Weighted Average Exercise Price
$17.75 - $24.21
 
263

 
1.26
 
$
20.96

 
263

 
$
20.96

$31.15 - $42.88
 
248

 
2.88
 
$
37.56

 
248

 
$
37.56

 
 
511

 
2.05
 
$
29.03

 
511

 
$
29.03
Summary of restricted stock units outstanding [Table Text Block]
A summary of RSU awards outstanding as of December 31, 2017, and activity during the three years then ended, is presented below:
(shares and intrinsic value in thousands)
Shares
 
Weighted Average Grant Date Fair Value Per Share
 
Weighted Average Remaining Contractual Term
(in years)
 
Aggregate Intrinsic Value
Outstanding at January 1, 2015
692

 
$
43.86

 
 
 
 
Granted
319

 
$
49.75

 
 
 
 
Vested
(267
)
 
$
42.49

 
 
 
 
Forfeited
(63
)
 
$
45.71

 
 
 
 
Outstanding at December 31, 2015
681

 
$
46.98

 
 
 
 
Granted
331

 
$
46.70

 
 
 
 
Vested
(270
)
 
$
45.13

 
 
 
 
Forfeited
(24
)
 
$
47.21

 
 
 
 
Outstanding at December 31, 2016
718

 
$
47.54

 
 
 
 
Granted
558

 
$
60.82

 
 
 
 
Vested
(284
)
 
$
46.52

 
 
 
 
Forfeited
(44
)
 
$
50.89

 
 
 
 
Outstanding at December 31, 2017
948

 
$
55.51

 
1.97
 
$
69,742

Outstanding and expected to vest at December 31, 2017
860

 
 
 
1.80
 
$
63,289
Performance Based Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Summary of performance-based awards outstanding [Table Text Block]
A summary of PSU awards outstanding as of December 31, 2017, and activity during the three years then ended, is presented below:
(shares and intrinsic value in thousands)
Shares
 
Weighted Average Grant Date Fair Value Per Share
 
Weighted Average Remaining Contractual Term
(in years)
 
Aggregate Intrinsic
Value
Outstanding at January 1, 2015
—

 
—

 
 
 
 
Granted
89

 
$
52.36

 
 
 
 
Vested
—

 
—

 
 
 
 
Forfeited or canceled
(78
)
 
$
52.35

 
 
 
 
Outstanding at December 31, 2015
11

 
$
52.35

 
 
 
 
Granted
101

 
$
46.26

 
 
 
 
Vested
(11
)
 
$
52.35

 
 
 
 
Forfeited or canceled
(2
)
 
$
46.87

 
 
 
 
Outstanding at December 31, 2016
99

 
$
46.25

 
 
 
 
Granted
88

 
$
63.99

 
 
 
 
Vested
(99
)
 
$
46.25

 
 
 
 
Forfeited or canceled
(9
)
 
$
63.99

 
 
 
 
Outstanding at December 31, 2017
79

 
$
63.99

 
0
 
$
5,819

Outstanding and expected to vest at December 31, 2017
79

 
 
 
0
 
$
5,819
Long-Term Performance-based Awards [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Summary of performance-based awards outstanding [Table Text Block]
A summary of PRSU awards outstanding as of December 31, 2017, and activity during the three years then ended, is presented below:
(shares and intrinsic value in thousands)
Shares
 
Weighted Average Grant Date Fair Value Per Share
 
Weighted Average Remaining Contractual Term
(in years)
 
Aggregate Intrinsic Value
Outstanding at January 1, 2015
61

 
$
55.51

 
 
 
 
Granted
72

 
$
52.47

 
 
 
 
Vested
—

 
—

 
 
 
 
Forfeited or canceled
(4
)
 
$
57.76

 
 
 
 
Outstanding at December 31, 2015
129

 
$
53.75

 
 
 
 
Granted
78

 
$
43.26

 
 
 
 
Vested
—

 
—

 
 
 
 
Forfeited or canceled
(57
)
 
$
55.35

 
 
 
 
Outstanding at December 31, 2016
150

 
$
47.65

 
 
 
 
Granted
71

 
$
63.00

 
 
 
 
Vested
—

 
—

 
 
 
 
Forfeited or canceled
(37
)
 
$
51.59

 
 
 
 
Outstanding at December 31, 2017
184

 
$
52.80

 
1.49
 
$
13,547

Outstanding and expected to vest at December 31, 2017
164

 

 
1.28
 
$
12,072