Capital Assets (Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Oct. 03, 2020	Sep. 28, 2019
Goodwill [Roll Forward]
Beginning Balance	$ 429,039	$ 369,275
Acquisitions	35,887	62,473
Goodwill impairment	(241,518)
Currency translation gain (loss)	5,232	(2,709)
Ending Balance	228,640	429,039
Test & Simulation
Goodwill [Roll Forward]
Beginning Balance	61,153	24,631
Acquisitions	35,887	39,181
Goodwill impairment	(53,344)
Currency translation gain (loss)	5,144	(2,659)
Ending Balance	48,840	61,153
Sensors
Goodwill [Roll Forward]
Beginning Balance	367,886	344,644
Acquisitions	0	23,292
Goodwill impairment	(188,174)
Currency translation gain (loss)	88	(50)
Ending Balance	$ 179,800	$ 367,886

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.

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