Recent Accounting Pronouncements - Components of Net Periodic Pension and Postretirement Benefits Credit (Detail) - USD ($) $ in Thousands	4 Months Ended
Apr. 21, 2018	Apr. 22, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately below)	$ 625,122	$ 608,068
Selling, distribution and administrative expenses	454,463	463,066
Income from operations	76,615	98,202
Other components of net periodic pension and postretirement benefits credit	$ (735)	(1,923)
As reported
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Materials, supplies, labor and other production costs (exclusive of depreciation and amortization shown separately below)		607,941
Selling, distribution and administrative expenses		461,270
Income from operations		$ 100,125

Net periodic defined benefits expense reversal of expense excluding service cost component.

No definition available.

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- Definition

The aggregate cost of goods produced and sold during the reporting period, excluding depreciation, depletion, and amortization.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

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