v3.19.2

Note 9 - Warrants (Details Textual) - Warrant In Connection with Oxford Finance Loan Agreement [Member] $ / shares in Units, $ in Millions	Jun. 30, 2019 shares	May 30, 2019 USD ($) $ / shares yr shares
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | shares		176,679
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 2.83
Warrants and Rights Outstanding, Term		10 years
Warrants and Rights Outstanding | $		$ 0.4
Class of Warrant or Right, Outstanding | shares	176,679
Measurement Input, Exercise Price [Member]
Warrants and Rights Outstanding, Measurement Input		2.83
Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input		2.66
Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input | yr		10
Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input		0.0222
Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input		0.8022
Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input		0

X

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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