Note 13 - Fair Value Measurements - Schedule of Fair Value Measurements Using Level 3 Inputs (Details) $ in Thousands	6 Months Ended
Jun. 30, 2020 USD ($)
Derivative Financial Instruments, Liabilities [Member]
Balance, December 31, 2019	$ 8
Issue of 2020/21 Notes embedded derivative liability
Total (gains) included in earnings	(8)
Balance, June 30, 2020
Embedded Derivative, 2020/21 Convertible Notes [Member]
Balance, December 31, 2019
Issue of 2020/21 Notes embedded derivative liability	2,848
Total (gains) included in earnings	(2,572)
Balance, June 30, 2020	$ 276

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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