Goodwill and Intangible Assets (Schedule of Goodwill) (Details) $ in Thousands	6 Months Ended
Mar. 30, 2019 USD ($)
Goodwill [Line Items]
Balance, October 1, 2018	$ 1,182,457
Frustum acquisition	53,673
Foreign currency translation adjustment	(6,589)
Balance, March 30, 2019	1,229,541
Software Products
Goodwill [Line Items]
Balance, October 1, 2018	1,152,720
Frustum acquisition	53,673
Foreign currency translation adjustment	(6,423)
Balance, March 30, 2019	1,199,970
Professional Services
Goodwill [Line Items]
Balance, October 1, 2018	29,737
Frustum acquisition	0
Foreign currency translation adjustment	(166)
Balance, March 30, 2019	$ 29,571

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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