Derivative Instruments Located on Condensed Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands	Jul. 15, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Assets	$ 6,409	$ 1,611
Derivative Liabilities	127	2,435
Commodity Contract \| Other Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Assets	6,245	1,576
Commodity Contract \| Other LongTerm Assets
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Assets	164	35
Commodity Contract \| Other Current Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Liabilities		$ 2,435
Commodity Contract \| Other LongTerm Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Derivative Liabilities	$ 127

Fair value of all asset derivatives designated as cash flow hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

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Fair value of all liability derivatives designated as cash flow hedging instruments.

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