Note 5 - Goodwill and Acquisition-related Intangible Assets, Net - Acquisition-related Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Gross Amount	$ 7,484	$ 7,484
Accumulated Amortization	(7,176)	(6,533)
Net Amount	308	951
Know-How [Member]
Gross Amount	1,018	1,018
Accumulated Amortization	(857)	(704)
Net Amount	161	314
Developed Technology Rights [Member]
Gross Amount	6,466	6,466
Accumulated Amortization	(6,319)	(5,829)
Net Amount	$ 147	$ 637

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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