Note 2 - Revenue - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Revenue	$ 73,710	$ 59,753
Percentage of revenue	100.00%	100.00%
UNITED STATES
Revenue	$ 24,177	$ 16,442
Percentage of revenue	33.00%	28.00%
Europe and ROW [Member]
Revenue	$ 10,421	$ 9,153
Percentage of revenue	14.00%	15.00%
Asia [Member]
Revenue	$ 39,112	$ 34,158
Percentage of revenue	53.00%	57.00%
Product [Member]
Revenue	$ 69,763	$ 54,687
Service [Member]
Revenue	$ 3,947	$ 5,066

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://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

Reference 2: 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

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration