Note 10 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands					12 Months Ended
	Oct. 04, 2022	Oct. 04, 2022	Sep. 29, 2022	Mar. 01, 2022	Dec. 31, 2023	Dec. 31, 2022	Aug. 11, 2023	Dec. 22, 2021
Common Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.0001	$ 0.0001	$ 0.0001	$ 0.0001
Proceeds from Issuance of Common Stock					$ 0	$ 46,834
Gain (Loss) on Issuance of Equity					(0)	(18,669)
Securities Purchase Agreement [Member] | Common Stock Warrants and Prefunded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				4,827,242
Class of Warrant or Right, Sale Price (in dollars per share)				$ 2.91
Securities Purchase Agreement [Member] | Prefunded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,013,850
Securities Purchase Agreement [Member] | Common Stock Warrant [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				2,260,388
Securities Purchase Agreement [Member] | Common Stock Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				2,260,388
September Purchase Agreements [Member] | Common Stock Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			10,643,034
September Purchase Agreements [Member] | Common Stock Warrants [Member] | Accredited Purchasers [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			10,526,368
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)			1
September Purchase Agreements [Member] | Common Stock Warrants [Member] | Insiders [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			116,666
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)			1
Private Placement [Member] | Securities Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)				6,436,322
Common Stock, Par or Stated Value Per Share (in dollars per share)				$ 0.0001
Stock and Warrants, Combined Issuance Price (in dollars per share)				$ 2.91
Proceeds from Issuance or Sale of Equity				$ 27,500
Registered Direct Offering [Member] | Securities Purchase Agreement [Member]
Gain (Loss) on Issuance of Equity					$ (12,800)
Registered Direct Offering [Member] | September Purchase Agreements [Member]
Stock Issued During Period, Shares, New Issues (in shares)	10,643,034	10,643,034	10,643,034
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			10,643,034
Proceeds from Issuance or Sale of Equity		$ 20,200
Proceeds from Issuance of Common Stock	$ 20,200
Gain (Loss) on Issuance of Equity						$ (12,800)
Registered Direct Offering [Member] | September Purchase Agreements [Member] | Accredited Purchasers [Member]
Stock Issued During Period, Shares, New Issues (in shares)			10,526,368
Stock and Warrants, Combined Issuance Price (in dollars per share)			$ 1.9
Registered Direct Offering [Member] | September Purchase Agreements [Member] | Insiders [Member]
Stock Issued During Period, Shares, New Issues (in shares)			116,666
Stock and Warrants, Combined Issuance Price (in dollars per share)			$ 2.1