Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Receivables and Assets (Details)

v3.10.0.1
Summary of Significant Accounting Policies - Receivables and Assets (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 27, 2018
Dec. 28, 2017
Accounts Receivable, Net [Abstract]    
Allowance for doubtful accounts $ 184 $ 349
Exposure from credit program 251  
Inventory Adjustments [Abstract]    
Inventory valuation reserves $ 4,265 $ 2,936
Vendor Relationships    
Intangible Assets, Net (Including Goodwill) [Abstract]    
Useful life, intangible assets 10 years 10 years
Maximum    
Accounts Receivable, Net [Abstract]    
Receivables collection period 5 days  
Maximum | Furniture, fixtures and equipment    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 7 years  
Maximum | Leasehold improvements    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 25 years  
Maximum | Computer software and hardware    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 7 years  
Minimum    
Accounts Receivable, Net [Abstract]    
Receivables collection period 3 days  
Minimum | Furniture, fixtures and equipment    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 2 years  
Minimum | Leasehold improvements    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 10 years  
Minimum | Computer software and hardware    
Property, Plant and Equipment, Gross [Abstract]    
Useful life, fixed assets 3 years