Note 1 - Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 8,875	$ 6,642
Less - accumulated depreciation	(2,813)	(2,698)
Property and equipment, net	6,062	3,944
Machinery and Equipment [Member]
Property and equipment, gross	3,887	2,992
Leasehold Improvements [Member]
Property and equipment, gross	3,034	1,734
Computer Equipment [Member]
Property and equipment, gross	621	721
Furniture and Fixtures [Member]
Property and equipment, gross	878	878
Construction in Progress [Member]
Property and equipment, gross	$ 455	$ 317

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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