Note 4 - Property and Equipment, Net - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Property and equipment	$ 937	$ 665
Accumulated depreciation	(565)	(441)
Property and equipment, net	372	224
Computer Equipment and Software [Member]
Property and equipment	141	167
Furniture and Fixtures [Member]
Property and equipment	318	244
Laboratory Equipment [Member]
Property and equipment	$ 478	$ 254

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (b)
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02(13))
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