Note 5 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property and equipment, gross	$ 6,053	$ 5,794
Accumulated depreciation and amortization	(1,663)	(1,359)
Property and equipment, net	4,390	4,435
Machinery and Equipment [Member]
Property and equipment, gross	3,540	3,357
Computer Equipment [Member]
Property and equipment, gross	283	284
Furniture and Fixtures [Member]
Property and equipment, gross	402	386
Leasehold Improvements [Member]
Property and equipment, gross	809	810
Software and Software Development Costs [Member]
Property and equipment, gross	296	284
Office Equipment [Member]
Property and equipment, gross	23	23
Construction in Progress [Member]
Property and equipment, gross	$ 700	$ 650

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

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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.

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