Stockholders' Equity (Tables)
 12 Months Ended
Dec. 31, 2016
Equity [Abstract]  
Schedule of Stock Option Activity

Stock option activity for the year ended December 31, 2016 is presented below (in thousands, except per share data and contractual term):

 

 

 

 

 

 

 

Weighted -

 

 

Weighted -

 

 

 

 

 

 

 

 

 

 

 

Average

 

 

Average

 

 

 

 

 

 

 

 

 

 

 

Exercise

 

 

Remaining

 

 

Aggregate

 

 

 

Number

 

 

Price Per

 

 

Contractual

 

 

Intrinsic

 

 

 

of Shares

 

 

Share

 

 

Term (in years)

 

 

Value

 

Outstanding at December 31, 2015

 

 

2,171

 

 

$

33.84

 

 

 

 

 

 

 

 

 

Granted

 

 

83

 

 

 

35.61

 

 

 

 

 

 

 

 

 

Exercised

 

 

(496

)

 

 

31.73

 

 

 

 

 

 

 

 

 

Forfeited

 

 

(218

)

 

 

35.68

 

 

 

 

 

 

 

 

 

Outstanding at December 31, 2016

 

 

1,540

 

 

$

34.35

 

 

 

6.44

 

 

$

13,235

 

Exercisable at December 31, 2016

 

 

883

 

 

$

33.53

 

 

 

5.22

 

 

$

8,315

 

Vested and expected to vest at December 31, 2016

 

 

1,474

 

 

$

34.32

 

 

 

6.36

 

 

$

12,727

 

 
Schedule of Restricted Stock Unit Activity

RSU activity for the year ended December 31, 2016 is presented below (in thousands, except per share data):

 

 

 

 

 

 

 

Weighted-

 

 

 

 

 

 

 

Average

 

 

 

Number of

 

 

Grant Date

 

 

 

Shares

 

 

Fair Value

 

Unvested at December 31, 2015

 

 

504

 

 

$

33.67

 

Granted

 

 

259

 

 

 

37.87

 

Vested

 

 

(171

)

 

 

34.05

 

Forfeited

 

 

(53

)

 

 

34.32

 

Unvested at December 31, 2016

 

 

539

 

 

$

35.50

 

 
Summary of Shares Purchased by Employees Under the Stock Purchase Plan

Shares purchased by employees under the Stock Purchase Plan are as follows (in thousands, except per share data):

 

 

Shares

 

 

Purchase

 

Purchase Period Ended

Purchased

 

 

Price

 

February 29, 2016

 

28

 

 

$

26.00

 

August 31, 2016

 

25

 

 

$

27.04

 

February 28, 2015

 

25

 

 

$

31.98

 

August 31, 2015

 

25

 

 

$

26.87