Capital Assets (Goodwill) (Details) $ in Thousands	6 Months Ended
Mar. 28, 2020 USD ($)
Goodwill [Roll Forward]
Balance, September 28, 2019	$ 429,039
Acquisitions	36,012
Currency translation	360
Balance, March 28, 2020	465,411
Test & Simulation
Goodwill [Roll Forward]
Balance, September 28, 2019	61,153
Acquisitions	35,980
Currency translation	351
Balance, March 28, 2020	97,484
Sensors
Goodwill [Roll Forward]
Balance, September 28, 2019	367,886
Acquisitions	32
Currency translation	9
Balance, March 28, 2020	$ 367,927

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
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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.

+ References

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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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