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.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for purchase accounting adjustments.

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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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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Goodwill and Intangibles - Schedule of Acquired Intangibles in Accompanying Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 572,952
Acquisitions	179,000
Disposal	(883)
Amortization	(79,098)	$ (80,731)	$ (46,095)
Foreign currency translation	(6,895)
Ending balance	$ 665,076	572,952
Weighted Average Amortization Period (years)	8 years
Customer Relationships, Contracts and Backlog
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 568,323
Acquisitions	137,000
Disposal	0
Amortization	(76,565)
Foreign currency translation	(6,366)
Ending balance	$ 622,392	568,323
Weighted Average Amortization Period (years)	8 years
Developed Technology
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 0
Acquisitions	42,000
Disposal	0
Amortization	(1,167)
Foreign currency translation	0
Ending balance	$ 40,833	0
Weighted Average Amortization Period (years)	12 years
Trade Names
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 2,102
Acquisitions	0
Disposal	0
Amortization	(920)
Foreign currency translation	1
Ending balance	$ 1,183	2,102
Weighted Average Amortization Period (years)	9 years
Lease Intangible Assets
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 2,527
Acquisitions	0
Disposal	(883)
Amortization	(446)
Foreign currency translation	(530)
Ending balance	$ 668	$ 2,527
Weighted Average Amortization Period (years)	2 years