Note 14 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Notes Tables

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	Years Ended December 31,
	2019			2018
Loss carry forwards	$	36,093		$	33,733
Derivative valuations		-			259
NQSO		2,060			1,964
Tax credits and other		116			438
Total deferred tax asset		38,269			36,394
Valuation allowance		(38,269	)		(36,394	)
Total deferred tax asset, net	$	-		$	-

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Years Ended December 31,
	2019			2018
Expected federal tax benefit		-21.0	%		-21.0	%
Permanent items		0.6	%		0.9	%
Net operating loss utilized or expired		0.0	%		0.0	%
Increase in valuation allowance and others		20.4	%		20.1	%
Effective tax rate		0	%		0	%