Goodwill And Intangible Assets (Components Of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2017	Oct. 01, 2016
Finite-Lived Intangible Assets
Weighted-Average Life (years)	12 years
Gross Carrying Amount	$ 345,185	$ 329,796
Accumulated Amortization	$ (236,367)	(216,236)
Customer-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	11 years
Gross Carrying Amount	$ 175,872	165,445
Accumulated Amortization	$ (128,019)	(117,434)
Technology-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 71,924	70,277
Accumulated Amortization	$ (55,069)	(52,060)
Program-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	19 years
Gross Carrying Amount	$ 66,458	64,774
Accumulated Amortization	$ (30,675)	(26,018)
Marketing-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 26,552	25,031
Accumulated Amortization	$ (19,251)	(17,649)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted-Average Life (years)	10 years
Gross Carrying Amount	$ 4,379	4,269
Accumulated Amortization	$ (3,353)	$ (3,075)

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/presentationRef
-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

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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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