Gross Margin, Percent

No definition available.

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

Amount, excluding 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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- References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Segments and Geographic Information - Operating Results By Segment (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 28, 2019 USD ($)	Sep. 28, 2019 USD ($)	Jun. 29, 2019 USD ($)	Mar. 30, 2019 USD ($)	Dec. 29, 2018 USD ($)	Sep. 29, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 28, 2019 USD ($) segment	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment									2
Segment Reporting Information [Line Items]
Revenues	$ 178,629	$ 140,604	$ 138,018	$ 132,213	$ 140,887	$ 134,989	$ 135,509	$ 118,290	$ 589,464	$ 529,675	$ 548,441
Gross profit	$ 74,305	$ 55,318	$ 55,352	$ 52,521	$ 56,022	$ 52,970	$ 56,218	$ 45,129	$ 237,496	$ 210,339	$ 215,597
Gross margin									40.30%	39.70%	39.30%
Probe Cards
Segment Reporting Information [Line Items]
Revenues									$ 491,363	$ 434,269	$ 454,794
Systems
Segment Reporting Information [Line Items]
Revenues									98,101	95,406	93,647
Operating Segments \| Probe Cards
Segment Reporting Information [Line Items]
Revenues									491,363	434,269	454,794
Gross profit									$ 211,382	$ 187,320	$ 195,903
Gross margin									43.00%	43.10%	43.10%
Operating Segments \| Systems
Segment Reporting Information [Line Items]
Revenues									$ 98,101	$ 95,406	$ 93,647
Gross profit									$ 50,927	$ 47,074	46,647
Gross margin									51.90%	49.30%
Corporate and Other
Segment Reporting Information [Line Items]
Revenues									$ 0	$ 0	0
Gross profit									$ (24,813)	$ (24,055)	$ (26,953)
Gross margin									0.00%	0.00%	0.00%