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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

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Note 1 - Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2018	Mar. 25, 2017
Net sales	$ 95,150	$ 95,150	$ 81,097
CHINA
Net sales		20,243
UNITED STATES
Net sales		14,478
Malaysia [Member]
Net sales		11,809
PHILIPPINES
Net sales		10,546
Rest of the World [Member]
Net sales		38,074
Systems [Member]
Net sales		54,905
Non-systems [Member]
Net sales		$ 40,245