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Note 1 - Summary of Significant Accounting Policies - Significant Customer Concentration Information (Details) - Customer Concentration Risk [Member] - Revenue Benchmark [Member] - Semiconductor Test and Inspection [Member] | 3 Months Ended
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Apr. 01, 2023 | Mar. 26, 2022
Customers individually accounting for more than 10% of net sales | 2 | 1
One Customer [Member] |  |
Percentage of net sales | 24.00% | 11.00%

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: 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 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-21 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482907/825-10-50-20 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482861/275-10-50-18 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482861/275-10-50-20 + Details
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