Note 7 - Embedded Derivatives Liabilities - Exercise of Warrants (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Proceeds	$ 1,117
The Series 2020 A Warrants [Member]
Common Stock Issued (in shares)	1,863,058
Proceeds	$ 1,117

The cash inflow associated with the amount received from holders exercising their stock warrants.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

Name:	us-gaap_ProceedsFromWarrantExercises
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration