Note 5 - Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Intangible assets, gross	$ 19,512	$ 17,236
Accumulated amortization	(7,641)	(6,987)
Total intangible assets, net	11,871	10,249
Trade Names [Member]
Intangible assets, gross	$ 555	555
Trade Names [Member] \| Minimum [Member]
Estimated useful lives (Year)	5 years
Trade Names [Member] \| Maximum [Member]
Estimated useful lives (Year)	7 years
Patents and Technological Know-how [Member]
Estimated useful lives (Year)	10 years
Intangible assets, gross	$ 15,653	13,377
Proprietary Software [Member]
Intangible assets, gross	$ 2,981	2,981
Proprietary Software [Member] \| Minimum [Member]
Estimated useful lives (Year)	3 years
Proprietary Software [Member] \| Maximum [Member]
Estimated useful lives (Year)	15 years
Other Intangible Assets [Member]
Intangible assets, gross	$ 323	$ 323
Other Intangible Assets [Member] \| Minimum [Member]
Estimated useful lives (Year)	3 years
Other Intangible Assets [Member] \| Maximum [Member]
Estimated useful lives (Year)	5 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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- Definition

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

+ References

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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