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Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 29, 2025	Sep. 27, 2025	Sep. 28, 2024
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 199,171	$ 199,171	$ 201,090
Foreign currency translation	(802)	1,670
Goodwill, ending balance		200,841
China Operations
Goodwill [Roll Forward]
Reduction - divesture			(1,117)
Probe Cards
Goodwill [Roll Forward]
Goodwill, beginning balance	177,369	177,369	178,424
Foreign currency translation	0	0
Goodwill, ending balance		177,369
Probe Cards | China Operations
Goodwill [Roll Forward]
Reduction - divesture			(1,055)
Systems
Goodwill [Roll Forward]
Goodwill, beginning balance	21,802	21,802	22,666
Foreign currency translation	$ (802)	1,670
Goodwill, ending balance		$ 23,472
Systems | China Operations
Goodwill [Roll Forward]
Reduction - divesture			$ (62)

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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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