Note 8 - Stock-based Compensation - Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Stock options and restricted stock units, net of forfeited	$ 20	$ 69	$ 40	$ 150
After-tax effect of stock-based compensation	$ 20	$ 69	$ 40	$ 150

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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