Goodwill And Intangible Assets (Components Of Intangible Assets) (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 28, 2020	Sep. 28, 2019
Finite-Lived Intangible Assets
Weighted-Average Life (years)	12 years
Gross Carrying Amount	$ 311,354	$ 291,132
Accumulated Amortization	$ (214,612)	(211,486)
Customer-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	11 years
Gross Carrying Amount	$ 141,843	132,697
Accumulated Amortization	$ (100,430)	(100,091)
Technology-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 77,471	69,220
Accumulated Amortization	$ (52,042)	(52,192)
Program-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	19 years
Gross Carrying Amount	$ 62,684	62,015
Accumulated Amortization	$ (37,937)	(35,680)
Marketing-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	8 years
Gross Carrying Amount	$ 25,222	23,139
Accumulated Amortization	$ (20,390)	(19,899)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted-Average Life (years)	10 years
Gross Carrying Amount	$ 4,134	4,061
Accumulated Amortization	$ (3,813)	$ (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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

No definition available.

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