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Inventories - Narrative (Detail) - USD ($)
3 Months Ended 9 Months Ended
Sep. 26, 2020
Sep. 28, 2019
Sep. 26, 2020
Sep. 28, 2019
Dec. 28, 2019
Geographic Valuation Methodologies Of Inventory [Line Items]          
Percentage of FIFO Inventory 56.00%   56.00%   58.00%
Effect of LIFO inventory liquidation on income $ 0 $ 0 $ 0 $ 0  
United States          
Geographic Valuation Methodologies Of Inventory [Line Items]          
Percentage of FIFO Inventory 29.00%   29.00%    
Percentage of LIFO Inventory 71.00%   71.00%