Derivative Financial Instruments and Fair Value Measurements (Disclosure of fair value, assets and liabilities measured on recurring basis) (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Derivative [Line Items]
Unrealized short-term derivative liability	$ (733)	$ (802)
Recurring basis [Member] \| Commodity futures and forward contracts [Member]
Derivative [Line Items]
Unrealized short-term derivative asset		284
Unrealized short-term derivative liability	(495)
Recurring basis [Member] \| Level 1 [Member] \| Commodity futures and forward contracts [Member]
Derivative [Line Items]
Unrealized short-term derivative asset		284
Unrealized short-term derivative liability	(495)
Recurring basis [Member] \| Level 2 [Member] \| Commodity futures and forward contracts [Member]
Derivative [Line Items]
Unrealized short-term derivative asset		0
Unrealized short-term derivative liability	0
Recurring basis [Member] \| Level 3 [Member] \| Commodity futures and forward contracts [Member]
Derivative [Line Items]
Unrealized short-term derivative asset		0
Unrealized short-term derivative liability	0
Recurring basis [Member] \| Not designated as hedging instruments [Member] \| Forward foreign currency contracts [Member]
Derivative [Line Items]
Derivative liability, notional amount	(670)	(73)
Recurring basis [Member] \| Not designated as hedging instruments [Member] \| Level 1 [Member] \| Forward foreign currency contracts [Member]
Derivative [Line Items]
Derivative liability, notional amount	0	0
Recurring basis [Member] \| Not designated as hedging instruments [Member] \| Level 2 [Member] \| Forward foreign currency contracts [Member]
Derivative [Line Items]
Derivative liability, notional amount	(670)	(73)
Recurring basis [Member] \| Not designated as hedging instruments [Member] \| Level 3 [Member] \| Forward foreign currency contracts [Member]
Derivative [Line Items]
Derivative liability, notional amount	$ 0	$ 0

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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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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