Note 11 - Warrants (Details) (USD $)	0 Months Ended	1 Months Ended		12 Months Ended		66 Months Ended							12 Months Ended						12 Months Ended			1 Months Ended	12 Months Ended			12 Months Ended		66 Months Ended	1 Months Ended
	Aug. 08, 2011	Jun. 03, 2013	Sep. 30, 2009	Dec. 31, 2013	Dec. 31, 2011	Aug. 31, 2015	Oct. 28, 2013	Oct. 27, 2013	May 30, 2013	Dec. 31, 2012	Dec. 31, 2010	Jan. 31, 2003	Dec. 31, 2013 Purchased Common Stock Exercise Of Warrant [Member]	Dec. 31, 2012 Purchased Common Stock Exercise Of Warrant [Member]	Dec. 31, 2011 Purchased Common Stock Exercise Of Warrant [Member]	Dec. 31, 2013 Warrant Liability [Member]	Dec. 31, 2012 Warrant Liability [Member]	Dec. 31, 2011 Warrant Liability [Member]	Dec. 31, 2013 Gross Amount [Member]	Dec. 31, 2012 Gross Amount [Member]	Dec. 31, 2011 Gross Amount [Member]	Oct. 28, 2013 Waived Warrant [Member]	Dec. 31, 2013 Waived Warrant [Member]	Dec. 31, 2013 Hercules Credit Agreement [Member]	Nov. 30, 2013 Hercules Credit Agreement [Member]	Dec. 31, 2011 Oxford and Horizon Credit Agreement [Member]	Jun. 30, 2012 Oxford and Horizon Credit Agreement [Member]	Aug. 31, 2015 Minimum [Member]	Sep. 30, 2009 Maximum [Member]	Dec. 31, 2013 Maximum [Member]
Note 11 - Warrants (Details) [Line Items]
Number of Warrants Issued (in Shares)				1,341,382	2,394,398																			194,986		11,415
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in Shares)																									194,986		11,415			463,000
Proceeds from Warrant Exercises																			$ 200,000	$ 10,200,000	$ 400,000
Conversion of Stock, Shares Issued (in Shares)	462,960												15,833	847,715	34,859
Proceeds from Issuance of Warrants			7,100,000
Proceeds from Issuance of Warrants, Net			6,300,000
Common Stock and Warrants Issued, Shares (in Shares)			484,478
Common Stock, Shares, Issued (in Shares)			224,239	13,737,970						8,437,267		253,691
Investment Warrants, Exercise Price (in Dollars per share)						$ 23.58
Common Stock Warrants Weighted Average Remaining Contractual Term																												6 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms				3 years 204 days																									66 months
Class of Warrant or Right, Outstanding (in Shares)				3,268,013	2,577,470		3,100,000	13,800,000	1,398,816	1,749,667	224,239
Reclassification From Equity to Liability		9,100,000																					9,110,302
Reverse Stock Split Reclassification From Liability to Equity																						5,300,000	(5,300,572)
Common Stock Warrant Liability				3,026	166,398					4,283,932	248,131
undefined																$ 8,100,000		$ 100,000
Common Stock Warrant Liability Benefit from Adjustment in Warrant Liability																	4,100,000