Recent Accounting Pronouncements Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019	Dec. 27, 2019
Credit Loss Disclosures [Abstract]
Accounts Receivable, before Allowance for Credit Loss	$ 270,000		$ 270,000		$ 256,000
Other Receivables	13,000		13,000		$ 11,000
Balance, beginning	4,798	$ 4,412	4,828	$ 4,771
Accounts Receivable, Credit Loss Expense (Reversal)	314	192	631	222
Accounts Receivable, Allowance for Credit Loss, Writeoff	38	146	291	690
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease)	85	(435)	(9)	12
Balance, ending	$ 5,159	$ 4,315	$ 5,159	$ 4,315

Credit Loss Disclosures [Abstract]

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- Definition

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522

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- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 310
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Balance Type:	credit
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- Definition

Amount of increase (decrease) in allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
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-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

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- Definition

Amount of direct write-downs of accounts receivable charged against the allowance.

+ References

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- Definition

Amount due from parties in nontrade transactions, classified as other.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

+ References

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