Note 13 - Stock Compensation Plan - Supplemental Stock Option Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Weighted average grant date fair value per option granted (in dollars per share)		$ 0.13
Fair value of options vested	$ 644	$ 911
Proceeds from exercise of stock options	21	463
Intrinsic value of options exercised	$ 13	$ 537

Amount of cash inflow from exercise of option under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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