Note 3 - Property and Equipment and Building Construction in Progress - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accumulated depreciation	$ (9,366)	$ (6,933)
	27,329	29,640
Office Equipment [Member]
Property, plant, and equipment, gross	476	461
Furniture and Fixtures [Member]
Property, plant, and equipment, gross	183	183
Land [Member]
Property, plant, and equipment, gross	1,418	1,418
Leasehold Improvements [Member]
Property, plant, and equipment, gross	802	802
Scientific Equipment [Member]
Property, plant, and equipment, gross	12,572	12,194
Vehicles [Member]
Property, plant, and equipment, gross	30	30
Building [Member]
Property, plant, and equipment, gross	21,013	21,013
Construction in Progress [Member]
Property, plant, and equipment, gross	$ 201	$ 472

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
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-Paragraph 1
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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 including building construction in process. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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