Note 2 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Retained Earnings (Accumulated Deficit), Ending Balance	$ (113,085)	$ (101,070)
Cash and Cash Equivalents, at Carrying Value, Ending Balance	$ 7,392	$ 5,585

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

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Balance Type:	credit
Period Type:	instant