v3.8.0.1

Note 14 - Net Loss Per Share of Common Stock - Common Stock Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Stock Option [Member]
Antidilutive securities (in shares)	8,767,783	6,395,879	4,699,121
Convertible Debt Securities [Member]
Antidilutive securities (in shares)		553,763	553,763
Warrant [Member]
Antidilutive securities (in shares)	176,730	692,611	180,155

X

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

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- Details

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X

- Details

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- Details

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