Note 13 - Quarterly Financial Information (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2014

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Financial Information [Table Text Block]

(in thousands, except per share data)
	Quarter Ended
	March 31,			June 30,			September 30,			December 31,
	2014			2014			2014			2014
Revenues	$	4		$	11		$	305		$	16
Gross profit (loss)		4			11			23			(59	)
Operating loss		(2,648	)		(2,453	)		(2,375	)		(2,883	)
Net loss		(4,694	)		(4,515	)		(4,566	)		(5,106	)
Basic and diluted net loss per common share	$	(0.29	)	$	(0.28	)	$	(0.28	)	$	(0.30	)

	Quarter Ended
	March 31,			June 30,			September 30,			December 31,
	2013			2013			2013			2013
Revenues	$	4		$	4		$	182		$	111
Gross profit (loss)		4			4			(110	)		(152	)
Operating loss		(3,944	)		(2,871	)		(3,107	)		(4,050	)
Net loss		(7,439	)		(4,461	)		(4,797	)		(5,980	)
Basic and diluted net loss per common share	$	(0.48	)		(0.29	)	$	(0.31	)	$	(0.38	)