Note 6 - Fair Value of Financial Instruments - Changes in Derivative Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024
Measurement at December 31, 2024	$ 121	$ 101	$ 224	$ 369	$ 411	$ 597
Change in fair value	(34)	20	(123)	(220)	(42)	(186)
Measurement at March 31, 2025	87	121	101	149	369	411
Notes Warrants [Member]
Measurement at December 31, 2024	107	90	197	338	362	334
Change in fair value	(29)	17	(107)	(203)	(24)	28
Measurement at March 31, 2025	78	107	90	135	338	362
Additional Warrants [Member]
Measurement at December 31, 2024	14	11	27	31	49	263
Change in fair value	(5)	3	(16)	(17)	(18)	(214)
Measurement at March 31, 2025	$ 9	$ 14	$ 11	$ 14	$ 31	$ 49