Capital Assets (Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2019	Sep. 29, 2018
Goodwill [Roll Forward]
Beginning Balance	$ 369,275	$ 369,762
Currency translation gain (loss)	(2,709)	(487)
Acquisitions	62,473
Ending Balance	429,039	369,275
Test & Simulation
Goodwill [Roll Forward]
Beginning Balance	24,631	25,109
Currency translation gain (loss)	(2,659)	(478)
Acquisitions	39,181
Ending Balance	61,153	24,631
Sensors
Goodwill [Roll Forward]
Beginning Balance	344,644	344,653
Currency translation gain (loss)	(50)	(9)
Acquisitions	23,292
Ending Balance	$ 367,886	$ 344,644

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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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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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