Goodwill and Intangibles - Schedule of Acquired Intangibles in Accompanying Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2018	Sep. 29, 2017	Sep. 30, 2016
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 332,920	$ 336,922
Acquisitions	416,952	35,905
Post-Acquisition Adjustments relating to prior year acquisition	(3,421)
Amortization	(80,731)	(46,095)	$ (47,608)
Foreign currency translation	(9,763)	4,305
Ending balance	$ 655,957	332,920	336,922
Weighted Average Amortization Period (years)	9 years
Customer Relationships, Contracts and Backlog
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 301,468	307,637
Acquisitions	412,300	29,803
Post-Acquisition Adjustments relating to prior year acquisition	200
Amortization	(75,375)	(39,679)
Foreign currency translation	(9,150)	3,707
Ending balance	$ 629,443	301,468	307,637
Weighted Average Amortization Period (years)	9 years
Developed Technology
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 14,462	14,311
Acquisitions	237	1,685
Post-Acquisition Adjustments relating to prior year acquisition	(1,921)
Amortization	(1,533)	(1,534)
Foreign currency translation	0	0
Ending balance	$ 11,245	14,462	14,311
Weighted Average Amortization Period (years)	8 years
Trade Names
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 6,699	4,786
Acquisitions	0	4,417
Post-Acquisition Adjustments relating to prior year acquisition	(1,700)
Amortization	(2,738)	(2,549)
Foreign currency translation	(159)	45
Ending balance	$ 2,102	6,699	4,786
Weighted Average Amortization Period (years)	8 years
Patents
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 10,180	10,027
Acquisitions	0	0
Post-Acquisition Adjustments relating to prior year acquisition	0
Amortization	(410)	(400)
Foreign currency translation	(454)	553
Ending balance	$ 9,316	10,180	10,027
Weighted Average Amortization Period (years)	24 years
Lease Intangible Assets
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 0	0
Acquisitions	4,415
Post-Acquisition Adjustments relating to prior year acquisition	0
Amortization	(625)
Foreign currency translation	0
Ending balance	$ 3,790	0	0
Weighted Average Amortization Period (years)	8 years
Other
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 111	161
Acquisitions	0	0
Post-Acquisition Adjustments relating to prior year acquisition	0
Amortization	(50)	(50)
Foreign currency translation	0	0
Ending balance	$ 61	$ 111	$ 161
Weighted Average Amortization Period (years)	2 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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