Goodwill and Intangible Assets (Narrative) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 30, 2019 USD ($) Segment	Mar. 30, 2019 USD ($) Segment	Sep. 30, 2018 USD ($)
Number of operating segments \| Segment		2
Number of reportable segments \| Segment	2
Intangible Assets, Net (Including Goodwill)	$ 1,421,913	$ 1,421,913	$ 1,382,659
Foreign currency translation adjustment		(6,589)
Goodwill	1,229,541	1,229,541	1,182,457
Professional Services
Intangible Assets, Net (Including Goodwill)	30,000	30,000	30,200
Foreign currency translation adjustment		(166)
Goodwill	29,571	29,571	29,737
Software Products
Intangible Assets, Net (Including Goodwill)	1,391,900	1,391,900	1,352,400
Foreign currency translation adjustment		(6,423)
Goodwill	$ 1,199,970	$ 1,199,970	$ 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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