Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Oct. 03, 2020
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	$ 64,282		$ 73,235
Accumulated Amortization	(44,348)		(51,470)
Net including IPRD	19,934		21,765
Amortization expense for intangible assets	(2,614)	$ (12,312)
Finite-Lived Intangible Assets, Future Amortization Expense [Abstract]
2021 (remainder)	7,632
2022	3,373
2023	2,779
2024	1,997
2025	1,996
2026	1,997
Thereafter	160
Net excluding IPRD	19,934
Existing technology
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	38,737		46,547
Accumulated Amortization	(31,547)		(37,630)
Net including IPRD	7,190		8,917
Customer Relationships [Member]
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	23,245		24,388
Accumulated Amortization	(11,769)		(12,923)
Net including IPRD	11,476		11,465
Production know-how [Domain]
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount	2,300		2,300
Accumulated Amortization	(1,032)		(917)
Net including IPRD	1,268		$ 1,383
Foreign exchange
Finite-Lived Intangible Assets, Net [Abstract]
Amortization expense for intangible assets	$ 1,800	$ (2,800)

Finite-lived Intangible Asset excluding IPRD, net

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

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No definition available.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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