Goodwill And Intangible Assets (Components Of Intangible Assets) (Details) - USD ($) $ in Thousands	Dec. 30, 2023	Sep. 30, 2023
Finite-Lived Intangible Assets
Weighted- Average Life (years)	12 years
Gross Carrying Amount	$ 269,769	$ 263,639
Accumulated Amortization	$ (197,106)	(192,002)
Customer-related
Finite-Lived Intangible Assets
Weighted- Average Life (years)	11 years
Gross Carrying Amount	$ 134,739	133,269
Accumulated Amortization	$ (95,943)	(93,648)
Technology-related
Finite-Lived Intangible Assets
Weighted- Average Life (years)	9 years
Gross Carrying Amount	$ 71,978	69,242
Accumulated Amortization	$ (57,381)	(56,106)
Program-related
Finite-Lived Intangible Assets
Weighted- Average Life (years)	23 years
Gross Carrying Amount	$ 38,566	37,465
Accumulated Amortization	$ (22,751)	(21,672)
Marketing-related
Finite-Lived Intangible Assets
Weighted- Average Life (years)	8 years
Gross Carrying Amount	$ 22,644	21,890
Accumulated Amortization	$ (19,386)	(18,995)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted- Average Life (years)	10 years
Gross Carrying Amount	$ 1,842	1,773
Accumulated Amortization	$ (1,645)	$ (1,581)

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.

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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
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(16))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482665/350-30-50-2

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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
-Topic 928
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483147/928-340-50-1

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-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482665/350-30-50-2

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483154/926-20-50-5

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