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Business Segments and Geographical Information - Additional Information (Details) - Segment
12 Months Ended
Dec. 29, 2018
Dec. 30, 2017
Segment Reporting Information [Line Items]    
Number of operating segments 1  
United States | Geographic Concentration Risk | Revenue, Total    
Segment Reporting Information [Line Items]    
Percentage of concentration risk 51.90% 55.30%