Note 7 - Derivative Obligations (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Jun. 30, 2016
Class of Warrant or Right, Outstanding	1,734,831		1,734,831		1,726,523
Derivative, Gain (Loss) on Derivative, Net, Total	$ (2,000)	$ 24,000	$ (2,000)	$ 591,000
Series A Warrant [Member]
Class of Warrant or Right, Outstanding						40,442