Earnings Per Share - Reconciliation of Basic and Diluted Weighted Average Shares Outstanding (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jul. 01, 2016
Jun. 30, 2017
Jul. 01, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Net income $ 5,461 $ 6,050 $ 12,129 $ 12,640
Weighted average common shares outstanding - basic (in shares) 10,987 10,702 10,948 10,665
Add: Dilutive impact of stock options (in shares) 78 103 60 89
Diluted weighted average common shares outstanding (in shares) 11,191 10,958 11,132 10,913
Basic earnings per share (in dollars per share) $ 0.50 $ 0.57 $ 1.11 $ 1.19
Diluted earnings per share (in dollars per share) $ 0.49 $ 0.55 $ 1.09 $ 1.16
Restricted Stock Units (RSUs)        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Add: Dilutive impact of restricted stock units (in shares) 126 153 124 159