v3.26.1
Operating Segments and Enterprise-Wide Information - Revenue by Segment, Recognition Type, and Geographic Area (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 27, 2026
Jun. 28, 2025
Jun. 27, 2026
Jun. 28, 2025
Disaggregation of Revenue [Line Items]        
Revenues $ 258,242 $ 195,798 $ 484,386 $ 367,154
Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 209,695 162,108 407,952 298,628
Systems        
Disaggregation of Revenue [Line Items]        
Revenues 48,547 33,690 76,434 68,526
Taiwan        
Disaggregation of Revenue [Line Items]        
Revenues 94,421 52,879 165,261 98,241
Taiwan | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 78,408 46,814 146,653 87,561
Taiwan | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 16,013 6,065 18,608 10,680
United States        
Disaggregation of Revenue [Line Items]        
Revenues 38,218 40,924 67,628 81,249
United States | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 26,499 32,849 48,321 60,633
United States | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 11,719 8,075 19,307 20,616
China        
Disaggregation of Revenue [Line Items]        
Revenues 16,891 9,400 28,253 23,015
China | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 8,372 4,633 16,178 12,785
China | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 8,519 4,767 12,075 10,230
South Korea        
Disaggregation of Revenue [Line Items]        
Revenues 73,424 57,129 153,986 100,300
South Korea | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 73,208 55,836 152,974 98,045
South Korea | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 216 1,293 1,012 2,255
Malaysia        
Disaggregation of Revenue [Line Items]        
Revenues 9,071 5,155 12,785 7,755
Malaysia | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 8,295 5,112 11,954 7,664
Malaysia | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 776 43 831 91
Japan        
Disaggregation of Revenue [Line Items]        
Revenues 4,805 14,666 13,087 24,985
Japan | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 3,780 7,080 8,862 12,259
Japan | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 1,025 7,586 4,225 12,726
Europe        
Disaggregation of Revenue [Line Items]        
Revenues 9,465 7,248 17,239 15,029
Europe | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 3,771 3,224 6,891 6,759
Europe | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 5,694 4,024 10,348 8,270
Singapore        
Disaggregation of Revenue [Line Items]        
Revenues 6,737 6,679 17,012 12,928
Singapore | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 5,132 5,489 12,214 10,360
Singapore | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 1,605 1,190 4,798 2,568
Rest of World        
Disaggregation of Revenue [Line Items]        
Revenues 5,210 1,718 9,135 3,652
Rest of World | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 2,230 1,071 3,905 2,562
Rest of World | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 2,980 647 5,230 1,090
Products transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenues 254,566 190,795 475,571 356,851
Products transferred at a point in time | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 208,065 160,552 404,350 295,273
Products transferred at a point in time | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 46,501 30,243 71,221 61,578
Products and services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenues 3,676 5,003 8,815 10,303
Products and services transferred over time | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 1,630 1,556 3,602 3,355
Products and services transferred over time | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 2,046 3,447 5,213 6,948
Foundry & Logic        
Disaggregation of Revenue [Line Items]        
Revenues 121,839 99,513 233,027 184,785
Foundry & Logic | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 121,839 99,513 233,027 184,785
Foundry & Logic | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 0 0 0 0
DRAM        
Disaggregation of Revenue [Line Items]        
Revenues 84,999 57,057 167,932 105,915
DRAM | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 84,999 57,057 167,932 105,915
DRAM | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 0 0 0 0
Flash        
Disaggregation of Revenue [Line Items]        
Revenues 2,857 5,538 6,993 7,928
Flash | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 2,857 5,538 6,993 7,928
Flash | Systems        
Disaggregation of Revenue [Line Items]        
Revenues 0 0 0 0
Systems        
Disaggregation of Revenue [Line Items]        
Revenues 48,547 33,690 76,434 68,526
Systems | Probe Cards        
Disaggregation of Revenue [Line Items]        
Revenues 0 0 0 0
Systems | Systems        
Disaggregation of Revenue [Line Items]        
Revenues $ 48,547 $ 33,690 $ 76,434 $ 68,526