Goodwill and Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 29, 2019	Jun. 29, 2019
Goodwill [Line Items]
Balance, October 1, 2018		$ 1,182,457
Foreign currency translation adjustment		(3,691)
Balance, June 29, 2019	$ 1,245,084	1,245,084
Software Products
Goodwill [Line Items]
Balance, October 1, 2018		1,152,720
Foreign currency translation adjustment		(3,598)
Balance, June 29, 2019	1,202,795	1,202,795
Professional Services
Goodwill [Line Items]
Balance, October 1, 2018		29,737
Foreign currency translation adjustment		(93)
Balance, June 29, 2019	42,289	42,289
Frustum [Member]
Goodwill [Line Items]
Goodwill, acquired		53,673
Frustum [Member] \| Software Products
Goodwill [Line Items]
Goodwill, acquired		53,673
Frustum [Member] \| Professional Services
Goodwill [Line Items]
Goodwill, acquired		0
other acquisition [Member]
Goodwill [Line Items]
Goodwill, acquired	$ 12,600	12,645
other acquisition [Member] \| Software Products
Goodwill [Line Items]
Goodwill, acquired		0
other acquisition [Member] \| Professional Services
Goodwill [Line Items]
Goodwill, acquired		$ 12,645

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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