Note 1 - Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2024	Dec. 30, 2023	Dec. 31, 2022
Net sales	$ 401,779	$ 636,322	$ 812,775
Systems [Member] \| Semiconductor Test and Inspection [Member]
Net sales	139,133	326,448	474,655
Non-systems [Member] \| Semiconductor Test and Inspection [Member]
Net sales	$ 262,646	$ 309,874	$ 338,120

Amount, including 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.

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+ Details