Goodwill And Intangible Assets (Components Of Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 27, 2020	Sep. 28, 2019
Finite-Lived Intangible Assets
Weighted-Average Life (years)	12 years
Gross Carrying Amount	$ 287,095	$ 291,132
Accumulated Amortization	$ (195,727)	(211,486)
Customer-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	11 years
Gross Carrying Amount	$ 142,372	132,697
Accumulated Amortization	$ (101,476)	(100,091)
Technology-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 77,628	69,220
Accumulated Amortization	$ (53,433)	(52,192)
Program-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	23 years
Gross Carrying Amount	$ 37,743	62,015
Accumulated Amortization	$ (16,354)	(35,680)
Marketing-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	8 years
Gross Carrying Amount	$ 25,218	23,139
Accumulated Amortization	$ (20,591)	(19,899)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted-Average Life (years)	10 years
Gross Carrying Amount	$ 4,134	4,061
Accumulated Amortization	$ (3,873)	$ (3,624)

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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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

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