Note 8 - Preferred Stock and Common Stock Warrants (Details Textual) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		12 Months Ended
	Apr. 17, 2023	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Gain (Loss) on Revaluation of Warrants		$ (367)	$ (6,304)
Series A Convertible Preferred Stock [Member]
Temporary Equity, Shares Outstanding (in shares)		85,454		82,948
Temporary Equity, Par or Stated Value Per Share (in dollars per share)				$ 0.0001
Preferred Stock, Convertible, Conversion Price (in dollars per share)		$ 5.27
Series B Convertible Preferred Stock [Member]
Temporary Equity, Shares Outstanding (in shares)		81,629		79,239
Temporary Equity, Par or Stated Value Per Share (in dollars per share)				$ 0.0001
Preferred Stock, Convertible, Conversion Price (in dollars per share)		$ 5.32
Series C Convertible Preferred Stock [Member]
Temporary Equity, Shares Outstanding (in shares)		61,156		59,366
Temporary Equity, Par or Stated Value Per Share (in dollars per share)				$ 0.0001
Preferred Stock, Convertible, Conversion Price (in dollars per share)		$ 2.87
Convertible Preferred Stock [Member]
Temporary Equity, Dividend Rate Percentage		12.00%
Temporary Equity, Issued Price Per Share (in dollars per share)		$ 1,000
Dividends, Preferred Stock, Paid-in-kind		$ 6,700	$ 5,700
Temporary Stock, Threshold Trading Days for Conversion (Day)				60 days
Temporary Stock, Threshold Consecutive Trading Days for Conversion (Day)				90 days
Temporary Stock, Conversion Price Minimum Percentage				175.00%
Temporary Stock, Maximum Business Days Following FID Event for Conversion (Day)				10 days
Convertible Preferred Stock [Member] | Subsequent Event [Member]
Dividends, Preferred Stock, Paid-in-kind	$ 6,700
Common Stock Warrants [Member]
Warrants and Rights Outstanding, Term (Year)				3 years