Note 1 - Description of Business and Basis of Presentation (Details Textual) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Retained Earnings (Accumulated Deficit), Total	$ 166,914	$ 163,836
Cumulative Effect, Period of Adoption, Adjustment [Member]
Retained Earnings (Accumulated Deficit), Total	$ (100)

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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