Note 10 - Stockholders' Equity (Details) (USD $)	0 Months Ended	1 Months Ended		12 Months Ended			0 Months Ended	9 Months Ended	0 Months Ended		1 Months Ended		0 Months Ended	1 Months Ended
	Jun. 03, 2013	Oct. 28, 2013	Aug. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 22, 2013	Sep. 30, 2013	Jan. 15, 2014	Feb. 02, 2013	Feb. 25, 2013	Feb. 26, 2013	May 30, 2013	Jun. 20, 2014	Oct. 30, 2014	Oct. 30, 2013	Oct. 29, 2013	Dec. 31, 2011	Dec. 31, 2010	Feb. 21, 2013
Note 10 - Stockholders' Equity (Details) [Line Items]
Shelf Registration Statement Amount (in Dollars)			$ 75,000,000
Proceed From Exercise Of Warrants And Options (in Dollars)					400,000	10,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period					30,893	904,144
Proceeds from Warrant Exercises (in Dollars)				0	261,944	10,106,557
Proceeds from Stock Options Exercised (in Dollars)				0	184,047	697,220
Common Stock, Par or Stated Value Per Share (in Dollars per share)				$ 0.01	$ 0.01
Stock Issued During Period, Value, New Issues (in Dollars)					18,217,852
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)				$ 8.18	$ 10.65	$ 15.17												$ 1,418
Proceeds from Issuance of Common Stock (in Dollars)				13,788,811	15,622,955
Proceed From Securities Offering (in Dollars)				18,000,000
Conversion of Stock, Shares Issued					15,833	847,715
Class of Warrant or Right, Outstanding				5,069,815	3,170,520	1,747,478									3,100,000			2,583,778
Common Stock, Shares Authorized				75,000,000	75,000,000
Reclassification From Equity to Liability (in Dollars)	9,100,000	5,300,000		476,261	9,110,302
Shares, Outstanding		9		1,751,773	863,462	729,825
Shares, Issued		9
Common Stock, Shares, Outstanding		2		19,984,203	13,604,975											13,604,975	61,226,873
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				1,744,755	861,905	725,529										900,000			691,809
Series A Convertible Preferred Stock (Member) | February 2013 Preferred Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Stock Issued During Period, Shares, New Issues							15,000.00422
Convertible Preferred Stock, Shares Issued upon Conversion												2,682,764
Dividends Payable, Current (in Dollars)												4,600,000
Conversion of Stock, Shares Converted								15,000.00422
Series A Warrant [Member] | January 2014 Common Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right									0.25
Series B Warrant [Member] | January 2014 Common Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right									0.25
Waived Warrants [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Class of Warrant or Right, Outstanding				1,398,816
January 2014 Common Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Stock Issued During Period, Shares, New Issues									3,603,604
Common Stock, Par or Stated Value Per Share (in Dollars per share)									$ 0.01
Class of Warrant or Right, Number of Securities Called by Warrants or Rights									1,801,802
Stock Issued During Period, Value, New Issues (in Dollars)									15,000,000
Common Stock, Shares Per Unit									1
Share Price (in Dollars per share)									$ 4.1625
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)									$ 4.10
ATM Agreement [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Stock Issued During Period, Shares, New Issues											1,195,927
Aggregate Offering Price (in Dollars)										25,000,000
Proceeds from Issuance of Common Stock (in Dollars)											6,800,000
Commission on Proceeds from ATM Shares, Percent				3.00%
Legal Fees (in Dollars)				50,000
February 2013 Preferred Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights												1,341,382
Class of Warrant or Right, Exercise Price of Warrants or Rights (in Dollars per share)																				$ 5.31
Proceeds from Issuance or Sale of Equity (in Dollars)												15,000,000
Warrants Issued Expiration Period												5 years
Warrants and Rights Outstanding (in Dollars)												5,400,000
Conversion of Stock, Shares Issued								2,682,764
May 2013 Common Stock Offering [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Stock Issued During Period, Shares, New Issues													1,392,109
Stock Issued During Period, Value, New Issues (in Dollars)													$ 9,800,000
Prior to Reverse Stock Split [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Class of Warrant or Right, Outstanding																	13,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number																	3,900,000
EGEN, Inc. [Member]
Note 10 - Stockholders' Equity (Details) [Line Items]
Share Price (in Dollars per share)				$ 3.48
Stock Issued During Period, Shares, Acquisitions				2,712,188
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares				670,070										2,712,188