Note 5 - Balance Sheet Details - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Property and equipment, gross	$ 1,443	$ 1,467
Less accumulated depreciation and amortization	(1,243)	(1,181)
Property and equipment, net	200	286
Leasehold Improvements [Member]
Property and equipment, gross	114	114
Furniture and Fixtures [Member]
Property and equipment, gross	317	314
Machinery and Equipment [Member]
Property and equipment, gross	$ 1,012	$ 1,039

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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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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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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+ References

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