Note 13 - Shareholders' Equity (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		1 Months Ended	12 Months Ended		44 Months Ended
	Apr. 07, 2022	May 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	May 31, 2019	Jun. 30, 2008
Preferred Stock, Shares Authorized (in shares)			2,500	2,500	2,500			2,500
Preferred Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001	$ 0.001	$ 0.001			$ 0.001
Common Stock, Shares Authorized (in shares)			50,000	50,000	50,000			50,000
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001	$ 0.001	$ 0.001			$ 0.001
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)			1	51	51	50
Common Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)			10	3,266
Common Stock [Member] | Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			2,200
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)		1,200
Common Stock [Member] | Equity Distribution Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)			0	222	720
Shares Issued, Price Per Share (in dollars per share)				$ 22.42	$ 22.42
Proceeds from Issuance of Common Stock				$ 4,984	$ 28,052
Sale of Common Shares Sales Agent Commission				112
Payments of Stock Issuance Costs				$ 202
Sale of Stock, Price Per Share (in dollars per share)				$ 38.97	$ 38.97
Common Stock Capital Value Reserved for Future Issuance			$ 1,948
Common Stock [Member] | Registered Direct Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	2,250
Shares Issued, Price Per Share (in dollars per share)	$ 25.9
Proceeds from Issuance of Common Stock	$ 58,275
Legal Fees	$ 55
Common Stock [Member] | Maximum [Member]
Aggregate Offering Price of Common Stock							$ 30,000
Common Stock [Member] | Maximum [Member] | Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)			770
Redeemable Preferred Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)			10
Temporary Equity, Redemption Price Per Share (in dollars per share)			$ 5
Dividends, Preferred Stock, Cash			$ 0
Undistributed Earnings Attributable to Preferred Stock			$ 0