Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies Goodwill (Details)

v3.8.0.1
Summary of Significant Accounting Policies Goodwill (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 30, 2017
Dec. 31, 2016
Dec. 31, 2015
Goodwill [Line Items]      
Impairment of Long-Lived Assets to be Disposed of $ 1,569 $ 0 $ 0
Goodwill 620,503 $ 615,682  
Goodwill, Acquired During Period 8,881    
Goodwill, Written off Related to Sale of Business Unit 0    
Goodwill, Other Increase (Decrease) $ (4,060)    
United States [Domain]      
Goodwill [Line Items]      
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount 4.00% 5.00% 8.00%
Goodwill $ 586,437 $ 583,780  
Goodwill, Acquired During Period 8,881    
Goodwill, Written off Related to Sale of Business Unit 0    
Goodwill, Other Increase (Decrease) (6,224)    
MEXICO      
Goodwill [Line Items]      
Goodwill 3,694 3,525  
Goodwill, Acquired During Period 0    
Goodwill, Written off Related to Sale of Business Unit 0    
Goodwill, Other Increase (Decrease) 169    
CANADA      
Goodwill [Line Items]      
Goodwill 30,372 $ 28,377  
Goodwill, Acquired During Period 0    
Goodwill, Written off Related to Sale of Business Unit 0    
Goodwill, Other Increase (Decrease) $ 1,995