Composition Of Certain Financial Statement Captions (Narrative) (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Sep. 27, 2019
Composition Of Certain Financial Statement Captions [Line Items]
Raw materials	$ 6,421	$ 8,031
Other Noncurrent Assets [Member]
Composition Of Certain Financial Statement Captions [Line Items]
Raw materials	3,200	$ 3,000
Land and Building [Member] \| Other Current Assets [Member]
Composition Of Certain Financial Statement Captions [Line Items]
Land and building held for sale	$ 2,200

Composition Of Certain Financial Statement Captions [Line Items].

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- Definition

Amount of assets held-for-sale that are not part of a disposal group.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=77912953&loc=d3e400-110220

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- Definition

Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a)(4))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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