Note 9 - Preferred Stock and Common Stock Warrants - Allocation of Net Cash Proceeds (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Gross proceeds	$ 39,500
Equity issuance costs	(62)
Net proceeds - Initial Fair Value Allocation	39,438
Series C Convertible Preferred Stock [Member]
Net proceeds - Initial Fair Value Allocation	37,807
Per balance sheet upon issuance	37,807
Series C Warrants [Member]
Net proceeds - Initial Fair Value Allocation	1,631
Per balance sheet upon issuance	$ 1,631

The amount of cash inflow from issuance of convertible preferred stock and common stock warrants after deducting issuance costs and after beneficial conversion feature allocation.

No definition available.

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

No definition available.

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- Definition

The cash inflow from issuance of convertible preferred stock and common stock warrants after deducting issuance costs.

+ References

No definition available.

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- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585

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