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=121558832&loc=d3e400-110220

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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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=120391452&loc=d3e13212-122682

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- Definition

Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer.

+ References

No definition available.

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Composition Of Certain Financial Statement Captions (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 25, 2020	Sep. 24, 2021	Sep. 25, 2020	Sep. 27, 2019
Composition Of Certain Financial Statement Captions [Line Items]
Unbilled accounts receivable		$ 97,500	$ 62,100
Raw materials		2,792	3,770
Gain on sale of assets		13,871	0	$ 0
Other Noncurrent Assets
Composition Of Certain Financial Statement Captions [Line Items]
Raw materials		1,900	$ 2,600
Land and Building [Member]
Composition Of Certain Financial Statement Captions [Line Items]
Gain on sale of assets	$ 13,900
Land and Building [Member] \| Other Current Assets
Composition Of Certain Financial Statement Captions [Line Items]
Land and buildings held for sale		$ 2,200