Derivative Instruments and Hedging Activities (Gain Loss On Derivative Cash Flow Hedges Reclassified From AOCI Into Income) (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 24, 2017	Sep. 30, 2018	Sep. 24, 2017
Derivative
Amount of cash flow hedges excluded from effectiveness testing	$ 0	$ 0	$ 0	$ 0
Not Designated as Hedging Instrument
Derivative
Amount of Gain/(Loss) Recognized in Income on Derivative	(85)	433	59	259
Not Designated as Hedging Instrument \| Commodity Contract \| Cost of Goods Sold
Derivative
Amount of Gain/(Loss) Recognized in Income on Derivative	$ (85)	$ 433	$ 59	$ 259

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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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 gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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