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Inventories - Narrative (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jun. 27, 2020
Jun. 29, 2019
Jun. 27, 2020
Jun. 29, 2019
Dec. 28, 2019
Geographic Valuation Methodologies Of Inventory [Line Items]          
Percentage of FIFO Inventory 58.00%   58.00%   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 31.00%   31.00%    
Percentage of LIFO Inventory 69.00%   69.00%