Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Summary of Stock-Based Compensation Activity - Stock Options) (Details)

v3.8.0.1
Stock-Based Compensation (Summary of Stock-Based Compensation Activity - Stock Options) (Details)
$ / shares in Units, $ in Thousands
3 Months Ended
Apr. 01, 2018
USD ($)
$ / shares
shares
Shares  
Outstanding at December 31, 2017 | shares 274,110
Exercised | shares (3,587)
Forfeited | shares (936)
Outstanding at April 1, 2018 | shares 269,587
Exercisable at April 1, 2018 | shares 267,250
Weighted Average Exercise Price  
Outstanding at December 31, 2017 | $ / shares $ 19.54
Exercised | $ / shares 9.83
Forfeited | $ / shares 32.02
Outstanding at April 1, 2018 | $ / shares 19.63
Exercisable at April 1, 2018 | $ / shares $ 19.53
Weighted Average Remaining Contractual Term (Years)  
Outstanding at April 1, 2018 3 years 11 months 1 day
Exercisable at April 1, 2018 3 years 10 months 28 days
Aggregate Intrinsic Value  
Outstanding at April 1, 2018 | $ $ 2,087
Exercisable at April 1, 2018 | $ $ 2,085