Goodwill And Intangible Assets (Components Of Intangible Assets) (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2018	Sep. 30, 2017
Finite-Lived Intangible Assets
Weighted-Average Life (years)	12 years
Gross Carrying Amount	$ 317,416	$ 345,185
Accumulated Amortization	$ (203,360)	(236,367)
Customer-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	11 years
Gross Carrying Amount	$ 147,256	175,872
Accumulated Amortization	$ (96,394)	(128,019)
Technology-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	9 years
Gross Carrying Amount	$ 71,442	71,924
Accumulated Amortization	$ (50,665)	(55,069)
Program-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	19 years
Gross Carrying Amount	$ 69,020	66,458
Accumulated Amortization	$ (34,007)	(30,675)
Marketing-Related
Finite-Lived Intangible Assets
Weighted-Average Life (years)	8 years
Gross Carrying Amount	$ 25,135	26,552
Accumulated Amortization	$ (18,642)	(19,251)
Other Intangible Assets
Finite-Lived Intangible Assets
Weighted-Average Life (years)	10 years
Gross Carrying Amount	$ 4,563	4,379
Accumulated Amortization	$ (3,652)	$ (3,353)

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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