Restructuring Charges and Asset Impairment - Schedule of Restructuring Activity and Asset Impairment (Detail) - USD ($) $ in Thousands	4 Months Ended
Apr. 18, 2020	Apr. 20, 2019
Restructuring Cost And Reserve [Line Items]
Asset impairment charges	$ 6,733	$ 100
Gain on sales of assets related to closed facilities	3,911	(6,925)
Provision for severance	2,198	149
Other costs associated with site closures	1,003	611
Changes in estimates	68	35
Restructuring and asset impairment	10,237	(5,662)
Business Restructuring Reserves [Member]
Restructuring Cost And Reserve [Line Items]
Provision for closing charges	325	366
Facility Closing [Member]
Restructuring Cost And Reserve [Line Items]
Gain on sales of assets related to closed facilities	$ (90)	$ (6,923)

Restructuring reserve revised change in estimates.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of restructuring charges, remediation cost, and asset impairment loss.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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