Note 14 - Subsequent Events	3 Months Ended	12 Months Ended
Mar. 31, 2024	Dec. 31, 2023
Notes to Financial Statements
Subsequent Events [Text Block]	12. Subsequent Events 2024 Private Placement On April 1, 2024, pursuant to and in accordance with the terms of a securities purchase agreement with certain purchasers named therein, the Company completed the private placement of an aggregate of 2,532,285 units, each comprised of (i) (A) one share of common stock or (B) one Pre-Funded Warrant and (ii) one Series A Warrant. The aggregate upfront gross proceeds from the 2024 Private Placement were approximately $50.0 million, before deducting approximately $3.5 million of offering fees and expenses at March 31, 2024, and additional gross proceeds of up to approximately $99.4 million may be received if the Series A Warrants are exercised in full for cash.	14. Subsequent Events 2024 Private Placement On March 28, 2024, the Company entered into a securities purchase agreement with certain purchasers named therein related to the private placement of an aggregate of 2,532,285 units, each comprised of (i) (A) one share of common stock or (B) one Pre-Funded Warrant and (ii) one Series A Warrant. The 2024 Private Placement is expected to close on or about April 1, 2024, subject to customary closing conditions. The aggregate upfront gross proceeds from the 2024 Private Placement are expected to be approximately $50 million, before deducting offering fees and expenses, and additional gross proceeds of up to approximately $99.4 million may be received if the Series A Warrants are exercised in full for cash. Pre-Funded Warrant Amendment and Exercise On February 26, 2024, following the effectiveness of an amendment eliminating certain beneficial ownership limitations set forth therein, the Company’s previously outstanding pre-funded warrant was exercised in full by the holder thereof pursuant to the cashless exercise provision in Section 2(c) of the pre-funded warrant. Upon exercise, 36 shares were withheld in lieu of a cash payment of the exercise price and the holder was issued 495,959 shares of common stock.

Note 14 - Subsequent Events

3 Months Ended

12 Months Ended

Mar. 31, 2024

Dec. 31, 2023

12. Subsequent Events

2024 Private Placement

On April 1, 2024, pursuant to and in accordance with the terms of a securities purchase agreement with certain purchasers named therein, the Company completed the private placement of an aggregate of 2,532,285 units, each comprised of (i) (A) one share of common stock or (B) one Pre-Funded Warrant and (ii) one Series A Warrant. The aggregate upfront gross proceeds from the 2024 Private Placement were approximately $50.0 million, before deducting approximately $3.5 million of offering fees and expenses at March 31, 2024, and additional gross proceeds of up to approximately $99.4 million may be received if the Series A Warrants are exercised in full for cash.

14. Subsequent Events

2024 Private Placement

On March 28, 2024, the Company entered into a securities purchase agreement with certain purchasers named therein related to the private placement of an aggregate of 2,532,285 units, each comprised of (i) (A) one share of common stock or (B) one Pre-Funded Warrant and (ii) one Series A Warrant. The 2024 Private Placement is expected to close on or about April 1, 2024, subject to customary closing conditions. The aggregate upfront gross proceeds from the 2024 Private Placement are expected to be approximately $50 million, before deducting offering fees and expenses, and additional gross proceeds of up to approximately $99.4 million may be received if the Series A Warrants are exercised in full for cash.

Pre-Funded Warrant Amendment and Exercise

On February 26, 2024, following the effectiveness of an amendment eliminating certain beneficial ownership limitations set forth therein, the Company’s previously outstanding pre-funded warrant was exercised in full by the holder thereof pursuant to the cashless exercise provision in Section 2(c) of the pre-funded warrant. Upon exercise, 36 shares were withheld in lieu of a cash payment of the exercise price and the holder was issued 495,959 shares of common stock.