Note 12 - Consolidated Statements of Changes in Equity - Changes in Equity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Balance	$ 46,441	$ 53,755
Stock option exercises	11	42
Stock-based compensation	182	281
Net loss	(1,768)	(2,163)
Balance	$ 44,866	$ 51,915
Preferred Stock [Member]
Balance (in shares)
Stock option exercises (in shares)
Balance (in shares)
Common Stock [Member]
Balance (in shares)	914,206,832	908,768,116
Balance	$ 914	$ 909
Stock option exercises (in shares)	109,792	415,476
Stock option exercises
Stock-based compensation
Net loss
Balance (in shares)	914,316,624	909,183,592
Balance	$ 914	$ 909
Warrant [Member]
Balance	18,179	18,179
Stock option exercises
Stock-based compensation
Net loss
Balance	18,179	18,179
Additional Paid-in Capital [Member]
Balance	286,276	284,894
Stock option exercises	11	42
Stock-based compensation	182	281
Net loss
Balance	286,469	285,217
AOCI Attributable to Parent [Member]
Balance	(258,854)	(250,154)
Stock option exercises
Stock-based compensation
Net loss	(1,768)	(2,163)
Balance	(260,622)	(252,317)
Noncontrolling Interest [Member]
Balance	(74)	(73)
Stock option exercises
Stock-based compensation
Net loss
Balance	$ (74)	$ (73)