Note 2 - Summary of Significant Accounting Policies - Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Raw material	$ 30	$ 11
Finished goods	3	5
Total	$ 33	$ 16

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.BB)
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-Section S99
-Paragraph 1
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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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-Publisher FASB
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-Section 45
-Paragraph 1
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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
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