Note 7 - Property and Equipment, Net - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 13,106	$ 13,259
Less accumulated depreciation	(6,011)	(6,115)
Property and equipment, net	7,095	7,144
Laboratory Equipment [Member]
Property and equipment, gross	3,834	2,951
Leasehold Improvements [Member]
Property and equipment, gross	5,999	5,663
Office Equipment Furniture and Fixtures [Member]
Property and equipment, gross	2,101	3,019
Software and Software Development Costs [Member]
Property and equipment, gross	870	1,626
Construction in Progress [Member]
Property and equipment, gross	$ 302

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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