Note 2 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Retained Earnings (Accumulated Deficit), Total	$ (137,576)	$ 137,600	$ (128,697)
Cash and Cash Equivalents, at Carrying Value, Total	$ 6,667	$ 6,700	$ 12,872

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

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