Capital Assets (Goodwill) (Details) $ in Thousands	9 Months Ended
Jun. 27, 2020 USD ($)
Goodwill [Roll Forward]
Balance, September 28, 2019	$ 429,039
Acquisitions	35,826
Currency translation	1,113
Balance, June 27, 2020	465,978
Test & Simulation
Goodwill [Roll Forward]
Balance, September 28, 2019	61,153
Acquisitions	35,794
Currency translation	1,093
Balance, June 27, 2020	98,040
Sensors
Goodwill [Roll Forward]
Balance, September 28, 2019	367,886
Acquisitions	32
Currency translation	20
Balance, June 27, 2020	$ 367,938

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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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