Gain or Loss Reclassified from Accumulated Other Comprehensive Income for Commodity Contracts (Detail) (USD $) In Thousands, unless otherwise specified	4 Months Ended
Apr. 25, 2015	Apr. 19, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net of tax	$ 1,587	$ 3,071
Commodity Contract
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gross (gain) loss reclassified from AOCI into income	2,504	4,917
Tax (benefit) expense	(964)	(1,893)
Net of tax	$ 1,540	$ 3,024

Amount before tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e689-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph c

-URI http://asc.fasb.org/extlink&oid=35706170&loc=d3e41638-113959

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