Inventories - Narratve (Detail) - USD ($)	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Geographic Valuation Methodologies Of Inventory [Line Items]
Percentage of FIFO Inventory	58.00%	61.00%
Effect of LIFO inventory liquidation on income	$ 0	$ 0	$ 0
United States
Geographic Valuation Methodologies Of Inventory [Line Items]
Percentage of FIFO Inventory	32.00%
Percentage of LIFO Inventory	68.00%

Geographic Valuation Methodologies of Inventory [Line Items]

No definition available.

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- Definition

The effect of liquidating LIFO (last in first out) inventory layers on income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SAB Topic 11.F)
-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100079-122729

+ Details

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- Definition

The percentage of FIFO (first in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

+ References

No definition available.

+ Details

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- Definition

The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

+ References

No definition available.

+ Details

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- Details

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