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Operating Segments and Enterprise-Wide Information - Revenue by Segment, Recognition Type, and Geographic Area (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 30, 2024	Apr. 01, 2023
Disaggregation of Revenue [Line Items]
Revenues	$ 168,725	$ 167,448
Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	136,701	127,328
Systems
Disaggregation of Revenue [Line Items]
Revenues	32,024	40,120
Taiwan
Disaggregation of Revenue [Line Items]
Revenues	29,877	40,329
Taiwan | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	27,179	38,897
Taiwan | Systems
Disaggregation of Revenue [Line Items]
Revenues	2,698	1,432
United States
Disaggregation of Revenue [Line Items]
Revenues	45,766	37,731
United States | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	35,596	24,641
United States | Systems
Disaggregation of Revenue [Line Items]
Revenues	10,170	13,090
China
Disaggregation of Revenue [Line Items]
Revenues	15,613	27,099
China | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	8,686	18,476
China | Systems
Disaggregation of Revenue [Line Items]
Revenues	6,927	8,623
South Korea
Disaggregation of Revenue [Line Items]
Revenues	50,717	20,775
South Korea | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	50,672	19,572
South Korea | Systems
Disaggregation of Revenue [Line Items]
Revenues	45	1,203
Malaysia
Disaggregation of Revenue [Line Items]
Revenues	1,863	11,270
Malaysia | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	1,608	10,324
Malaysia | Systems
Disaggregation of Revenue [Line Items]
Revenues	255	946
Japan
Disaggregation of Revenue [Line Items]
Revenues	8,542	10,977
Japan | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	4,347	7,136
Japan | Systems
Disaggregation of Revenue [Line Items]
Revenues	4,195	3,841
Europe
Disaggregation of Revenue [Line Items]
Revenues	8,849	9,426
Europe | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	3,528	3,426
Europe | Systems
Disaggregation of Revenue [Line Items]
Revenues	5,321	6,000
Singapore
Disaggregation of Revenue [Line Items]
Revenues	4,758	5,340
Singapore | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	3,516	3,200
Singapore | Systems
Disaggregation of Revenue [Line Items]
Revenues	1,242	2,140
Rest of the world
Disaggregation of Revenue [Line Items]
Revenues	2,740	4,501
Rest of the world | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	1,569	1,656
Rest of the world | Systems
Disaggregation of Revenue [Line Items]
Revenues	1,171	2,845
Products transferred at a point in time
Disaggregation of Revenue [Line Items]
Revenues	164,425	163,388
Products transferred at a point in time | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	135,641	126,678
Products transferred at a point in time | Systems
Disaggregation of Revenue [Line Items]
Revenues	28,784	36,710
Products and services transferred over time
Disaggregation of Revenue [Line Items]
Revenues	4,300	4,060
Products and services transferred over time | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	1,060	650
Products and services transferred over time | Systems
Disaggregation of Revenue [Line Items]
Revenues	3,240	3,410
Foundry & Logic
Disaggregation of Revenue [Line Items]
Revenues	86,768	101,562
Foundry & Logic | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	86,768	101,562
Foundry & Logic | Systems
Disaggregation of Revenue [Line Items]
Revenues	0	0
DRAM
Disaggregation of Revenue [Line Items]
Revenues	45,896	19,890
DRAM | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	45,896	19,890
DRAM | Systems
Disaggregation of Revenue [Line Items]
Revenues	0	0
Flash
Disaggregation of Revenue [Line Items]
Revenues	4,037	5,876
Flash | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	4,037	5,876
Flash | Systems
Disaggregation of Revenue [Line Items]
Revenues	0	0
Systems
Disaggregation of Revenue [Line Items]
Revenues	32,024	40,120
Systems | Probe Cards
Disaggregation of Revenue [Line Items]
Revenues	0	0
Systems | Systems
Disaggregation of Revenue [Line Items]
Revenues	$ 32,024	$ 40,120

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