Goodwill and Intangible Assets Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Apr. 01, 2022	Mar. 26, 2021	Apr. 01, 2022	Mar. 26, 2021	Sep. 24, 2021
Finite-Lived Intangible Assets [Line Items]
Cost	$ 451,526		$ 451,526		$ 432,074
Accumulated Amortization	(325,245)		(325,245)		(309,184)
Total	126,281		126,281		122,890
Purchases of intangible assets	$ 11,500
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	16 years
Amortization of Intangible Assets	$ 7,600	$ 7,300	15,600	$ 14,600
Acquired Patents And Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Cost	362,271		362,271		343,280
Accumulated Amortization	(247,548)		(247,548)		(233,789)
Total	114,723		114,723		109,491
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Cost	66,210		66,210		65,822
Accumulated Amortization	(54,869)		(54,869)		(52,730)
Total	11,341		11,341		13,092
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Cost	23,045		23,045		22,972
Accumulated Amortization	(22,828)		(22,828)		(22,665)
Total	$ 217		$ 217		$ 307

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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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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The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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