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Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 30, 2023 | Dec. 31, 2022
Goodwill [Roll Forward] |  |
Goodwill, beginning balance | $ 211,444 | $ 212,299
Reduction - FRT divestiture | (10,660) |
Foreign currency translation | 306 | (1,405)
Goodwill, ending balance | 201,090 | 211,444
Woburn |  |
Goodwill [Roll Forward] |  |
Goodwill, acquired during period |  | 550
Probe Cards |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning balance | 178,424 | 178,424
Reduction - FRT divestiture | 0 |
Foreign currency translation | 0 | 0
Goodwill, ending balance | 178,424 | 178,424
Probe Cards | Woburn |  |
Goodwill [Roll Forward] |  |
Goodwill, acquired during period |  | 0
Systems |  |
Goodwill [Roll Forward] |  |
Goodwill, beginning balance | 33,020 | 33,875
Reduction - FRT divestiture | (10,660) |
Foreign currency translation | 306 | (1,405)
Goodwill, ending balance | $ 22,666 | 33,020
Systems | Woburn |  |
Goodwill [Roll Forward] |  |
Goodwill, acquired during period |  | $ 550

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