Note 5 - Stock-based Compensation - Schedule of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Stock-based compensation expense	$ 245	$ 86
General and Administrative Expense [Member]
Stock-based compensation expense	$ 245	$ 86

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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-Publisher FASB
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