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Segments and Geographic Information - Revenue by Timing of Recognition (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 28, 2024 | Dec. 30, 2023 | Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | $ 763,599 | $ 663,102 | $ 747,937
Products transferred at a point in time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 742,779 | 649,769 | 732,194
Services transferred over time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 20,820 | 13,333 | 15,743
Probe Cards |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 625,960 | 497,903 | 591,422
Probe Cards | Products transferred at a point in time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 620,598 | 494,624 | 587,738
Probe Cards | Services transferred over time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 5,362 | 3,279 | 3,684
Systems |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 137,639 | 165,199 |
Systems | Products transferred at a point in time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | 122,181 | 155,145 | 144,456
Systems | Services transferred over time |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |  |  |
Revenues | $ 15,458 | $ 10,054 | $ 12,059

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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 41 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-41 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 270 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482964/270-10-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (ee) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-32 Reference 4: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-32 Reference 5: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-32 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 924 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 11.L) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479941/924-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-5 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 30 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-30 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-42 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-22 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 40 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-40 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-22 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-4 + Details
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