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		9 Months Ended
	Sep. 24, 2022	Sep. 25, 2021	Sep. 25, 2021
Customers individually accounting for more than 10% of net sales	1	2	1
One Customer [Member]
Percentage of net sales	13.00%	32.00%	14.00%