Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation (Narrative)(Details)

v3.8.0.1
Stock-Based Compensation (Narrative)(Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 25, 2016
Dec. 27, 2015
Stock-based compensation $ 2,880 $ 2,193 $ 1,718
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount $ 218 160 114
ShareBasedCompensationArrangementByShareBasedPaymentAwardEstimatedFairValueOfCommonStockPerShare $ 28.05    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value $ 600 9,100  
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value 300 $ 500 $ 600
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized 100    
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options $ 5,300    
2012 Omnibus Equity Incentive Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period 10 years    
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant 706,101    
Employee Stock Option [Member] | 2012 Omnibus Equity Incentive Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 20.00%    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 5 years    
Minimum [Member] | Restricted Stock Units (RSUs) [Member] | 2012 Omnibus Equity Incentive Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 4 years    
Maximum [Member] | Restricted Stock Units (RSUs) [Member] | 2012 Omnibus Equity Incentive Plan [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period 5 years