Goodwill And Intangible Assets (Components Of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2019	Sep. 29, 2018
Finite-Lived Intangible Assets
Weighted-Average Life (years)	12 years
Gross Carrying Amount	$ 291,132	$ 297,554
Accumulated Amortization	$ (211,486)	(202,017)
Customer-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	11 years
Gross Carrying Amount	$ 132,697	135,379
Accumulated Amortization	$ (100,091)	(96,090)
Technology-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 69,220	69,393
Accumulated Amortization	$ (52,192)	(49,731)
Program-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	19 years
Gross Carrying Amount	$ 62,015	64,988
Accumulated Amortization	$ (35,680)	(33,740)
Marketing-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	8 years
Gross Carrying Amount	$ 23,139	23,489
Accumulated Amortization	$ (19,899)	(18,868)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted-Average Life (years)	10 years
Gross Carrying Amount	$ 4,061	4,305
Accumulated Amortization	$ (3,624)	$ (3,588)

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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