Capital Assets (Goodwill) (Details) $ in Thousands	3 Months Ended
Dec. 28, 2019 USD ($)
Goodwill [Roll Forward]
Balance, September 28, 2019	$ 429,039
Acquisitions	(46)
Currency translation	845
Balance, December 28, 2019	429,838
Test & Simulation
Goodwill [Roll Forward]
Balance, September 28, 2019	61,153
Acquisitions	0
Currency translation	833
Balance, December 28, 2019	61,986
Sensors
Goodwill [Roll Forward]
Balance, September 28, 2019	367,886
Acquisitions	(46)
Currency translation	12
Balance, December 28, 2019	$ 367,852

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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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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