Goodwill and Intangible Assets (Narrative) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 29, 2018 USD ($) Segment	Sep. 30, 2017 Segment	Sep. 30, 2018 USD ($)
Number of operating segments \| Segment	2
Number of reportable segments \| Segment	2	3
Intangible Assets, Net (Including Goodwill)	$ 1,435,985		$ 1,382,659
Foreign currency translation adjustment	(5,333)
Goodwill	1,230,901		1,182,457
Professional Services
Intangible Assets, Net (Including Goodwill)	30,100		30,200
Foreign currency translation adjustment	(134)
Goodwill	29,603		29,737
Software Products
Intangible Assets, Net (Including Goodwill)	1,405,900		1,352,400
Foreign currency translation adjustment	(5,199)
Goodwill	$ 1,201,298		$ 1,152,720

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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