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Stock-Based Compensation - Additional Information (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
12 Months Ended
Dec. 30, 2017
Dec. 31, 2016
Dec. 26, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock-based compensation expense $ 7.5 $ 6.4 $ 6.2
Employee Stock Option [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average grant-date fair value of options granted (in dollars per share) $ 9.38 $ 7.87 $ 7.58
Total intrinsic value of options exercised $ 10.2 $ 2.5 $ 3.1
Fair value of options vested 1.0 0.3 0.8
Aggregate intrinsic value of all outstanding options $ 12.4    
Weighted average remaining contractual term of all outstanding options 6 years 2 months    
Outstanding options, exercisable (in shares) 476    
Aggregate intrinsic value of current exercisable shares $ 8.5    
Weighted average exercise price (in dollars per share) $ 17.57    
Weighted average remaining contractual term 4 years 6 months 18 days    
Compensation for stock awards not yet recognized $ 1.9    
Compensation recognition period 3 years 6 months 18 days    
Shares available for future issuance (in shares) 700    
Employee Stock Option [Member] | Maximum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Stock options vesting period 5 years    
Stock options expiration period 10 years    
Restricted Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Fair value of options vested $ 3.5 $ 4.7 $ 4.8
Compensation for stock awards not yet recognized $ 15.8    
Compensation recognition period 3 years 2 months 24 days    
Granted (in dollars per share) $ 30.97 $ 34.04 $ 32.54
Aggregate intrinsic value $ 27.7