Note 6 - Preferred Stock (Details Textual) - USD ($)			3 Months Ended		6 Months Ended	9 Months Ended		12 Months Ended		24 Months Ended	33 Months Ended
	Oct. 06, 2023	Mar. 31, 2023	Sep. 30, 2025	Mar. 31, 2025	Jun. 30, 2025	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Sep. 30, 2025	Jun. 05, 2025	Mar. 30, 2023
Preferred Stock, Shares Authorized (in shares)			5,000,000			5,000,000		5,000,000		5,000,000	5,000,000
Preferred Stock, Shares Designated (in shares)			1,983,250			1,983,250					1,983,250
Preferred Stock, Shares Issued (in shares)			150			150		545		545	150
Preferred Stock, Shares Outstanding (in shares)			150			150		545		545	150
Preferred Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 975
Warrants and Rights Outstanding, Term (Month)				3 years
Class of Warrant or Right, Percentage of Securities Called by Warrants or Rights				100.00%
Class of Warrant or Right, Exercised (in shares)			575			575	1,648
Proceeds from Warrant Exercises			$ 561,000			$ 561,000	$ 1,607,000
Proceeds From Warrant Exercises, Net			$ 516,000			$ 516,000	1,478,000
Class of Warrant or Right, Outstanding (in shares)			30,527			30,527					30,527
Class of Warrant or Right, Cash Fee, Percentage of Proceeds					8.00%
Class of Warrant or Right, Cash Fee			$ 45,000			$ 45,000	$ 129,000
Conversion of Series F Preferred Stock to Common Stock [Member]
Conversion of Stock, Shares Converted (in shares)			780			970	3,033
Conversion of Stock, Amount of Dividends Converted			$ 20,000			$ 39,000	$ 194,000
Conversion of Stock, Shares Issued (in shares)			212,454			257,617	288,968	288,947	352,624	641,571	899,188
Series F Preferred Stock [Member]
Preferred Stock, Shares Outstanding (in shares)			150			150		545	1,930	545	150
Preferred Stock, Convertible, Conversion Price (in dollars per share)			$ 3.77			$ 3.77	$ 11.17	$ 11.17	$ 13.6	$ 11.17	$ 3.77	$ 3.77	$ 68.4
Preferred Stock, Convertible, Conversion Price Percentage													80.00%
Preferred Stock, Convertible, Floor Price (in dollars per share)	$ 11.17
Preferred Stock, Stated Value Per Share (in dollars per share)	$ 1,000
Preferred Stock, Dividend Rate, Percentage	9.00%			20.00%
Conversion of Stock, Shares Converted (in shares)						970		3,033
Dividends Payable			$ 19,000,000			$ 19,000,000		$ 29,000,000	$ 136,000,000	$ 29,000,000	$ 19,000,000
Stock Issued During Period, Shares, Warrants Exercised (in shares)			575			575	1,648
Private Placement [Member]
Proceeds from Issuance or Sale of Equity		$ 6,386,000
Proceeds from Issuance or Sale of Equity, Net		5,364,000
Payments of Stock Issuance Costs		$ 1,022,000
Maximum [Member]
Preferred Stock, Shares Authorized (in shares)			5,000,000			5,000,000					5,000,000