Note 14 - Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2018

Notes Tables

Quarterly Financial Information [Table Text Block]

(in thousands, except per share data)
	Quarter Ended
	March 31,			June 30,			September 30,			December 31,
	201 8			201 8			201 8			201 8
Revenues	$	108		$	109		$	112		$	111
Gross profit		108			109			112			111
Operating loss		(2,486	)		(2,255	)		(2,488	)		(3,992	)
Net loss		(5,971	)		(6,032	)		(6,240	)		(8,030	)
Basic and diluted net loss per common share	$	(0.26	)	$	(0.25	)	$	(0.26	)	$	(0.33	)

	Quarter Ended
	March 31,			June 30,			September 30,			December 31,
	2017			201 7			201 7			201 7
Revenues	$	108		$	108		$	111		$	110
Gross profit (loss)		108			108			111			110	)
Operating loss		(4,113	)		(2,105	)		(2,414	)		(4,008	)
Net loss		(7,227	)		(13,570	)		(5,992	)		(7,075	)
Basic and diluted net loss per common share	$	(0.33	)		(0.60	)	$	(0.26	)	$	(0.31	)