Note 8 - Stockholders' Equity (Deficit) (Details Textual)					3 Months Ended		9 Months Ended
	Jun. 10, 2024 USD ($) $ / shares shares	Jul. 24, 2023 USD ($) $ / shares shares	May 09, 2023 USD ($) $ / shares shares	Jan. 19, 2023 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) shares	Dec. 31, 2023 shares	Jun. 30, 2023 shares	Jun. 08, 2023 USD ($)
Class of Stock [Line Items]
Preferred Stock, Shares Authorized (in shares)					15,000,000		15,000,000		15,000,000
Common Stock, Shares, Outstanding (in shares)					12,223,758		12,223,758		9,451,753
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)					437,089		437,089
Share-Based Compensation Arrangement by Share-Based Payment Award, Options and Warrants, Outstanding, Number (in shares)					866,875		866,875
Preferred Stock, Shares Issued (in shares)					0		0
Proceeds from Warrant Exercises | $							$ 0	$ 6,886,000
Common Stock, Shares Authorized (in shares)					45,000,000		45,000,000		45,000,000
Common Stock [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues (in shares)					63,700	1,600,000	819,565	1,875,961
Stock Issued During Period, Shares, Warrants Exercised (in shares)								313,000
December 2022 and January 2023 Warrants [Member]
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares			$ 25
Class of Warrant or Right, Exercised During Period (in shares)			313,000
Proceeds from Warrant Exercises | $			$ 6,900,000
Stock Issued During Period, Shares, Warrants Exercised (in shares)			313,000
Fair Value Adjustment of Warrants | $			$ 383,000
December 2022 and January 2023 Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			4.81
December 2022 and January 2023 Warrants [Member] | Measurement Input, Expected Term [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			1
December 2022 and January 2023 Warrants [Member] | Measurement Input, Price Volatility [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			42.5
December 2022 and January 2023 Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			0
Modified Warrants [Member]
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares			$ 22
New Warrants [Member]
Class of Stock [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares			$ 30
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			313,000
New Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			4.81
New Warrants [Member] | Measurement Input, Expected Term [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			1.5
New Warrants [Member] | Measurement Input, Price Volatility [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			43.7
New Warrants [Member] | Measurement Input, Expected Dividend Rate [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input			0
Underwritten Public Offering [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues (in shares)	731,750	1,600,000
Warrant exercise price | $ / shares	$ 26
Warrants exercisable term	36 months
Shares Issued, Price Per Share (in dollars per share) | $ / shares	$ 20.5	$ 17.77			$ 19.37		$ 19.37
Underwriting Agreement, Discount Percentage		6.50%			5.50%		5.50%
Proceeds from Issuance of Common Stock, Net | $	$ 13,700,000	$ 28,200,000
Underwritten Public Offering [Member] | Common Stock [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share (in dollars per share) | $ / shares		$ 19
Underwritten Public Offering [Member] | Measurement Input, Risk Free Interest Rate [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input	4.57
Underwritten Public Offering [Member] | Measurement Input, Expected Term [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input	3
Underwritten Public Offering [Member] | Measurement Input, Price Volatility [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input	57
Underwritten Public Offering [Member] | Measurement Input, Expected Dividend Rate [Member] | Fair Value, Inputs, Level 2 [Member]
Class of Stock [Line Items]
Warrants and Rights Outstanding, Measurement Input	0
Sales Agreement [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues (in shares)							87,815	158,461
Proceeds from Issuance of Common Stock, Net | $							$ 1,800,000	$ 4,100,000
Sales Agreement [Member] | Common Stock [Member]
Class of Stock [Line Items]
Balance remaining from sales agreement | $					$ 32,800,000		$ 32,800,000
Sales Agreement [Member] | Cantor Fitzgerald & Co. [Member]
Class of Stock [Line Items]
Offering Agreement, Maximum Aggregate Common Shares May be Offered | $											$ 40,000,000
Commission Fee, Percentage of Gross Proceeds of Shares Sold, Maximum											2.75%
Private Placement [Member]
Class of Stock [Line Items]
Stock Issued During Period, Shares, New Issues (in shares)				117,500
Rights Agreement, Exercise Price (in dollars per share) | $ / shares				$ 25
Proceeds from Issuance of Common Stock, Net | $				$ 2,300,000
Private Placement [Member] | January 2023 Warrants [Member]
Class of Stock [Line Items]
Shares Issued, Price Per Share (in dollars per share) | $ / shares				$ 20
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 25
Restricted Stock [Member]
Class of Stock [Line Items]
Common Stock, Shares, Outstanding (in shares)					12,223,758		12,223,758
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in shares)					437,089		437,089		433,528	429,376