Note 3 - Equity Offerings (Details Textual)	Jan. 20, 2017 USD ($) $ / shares shares	Sep. 07, 2016 USD ($)	Aug. 10, 2016 USD ($) shares	Aug. 05, 2016 $ / shares	Jul. 10, 2016 USD ($) $ / shares	Jul. 10, 2016 USD ($) $ / shares	May 26, 2016 USD ($) $ / shares shares	Aug. 02, 2016 $ / shares shares	Aug. 01, 2016 shares
Preferred Stock, Par or Stated Value Per Share | $ / shares								$ 0.01
Common Stock, Shares Authorized | shares								700,000,000	150,000,000
Preferred Stock, Shares Authorized | shares								25,000,000
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio				20
Common Stock Purchase Agreements [Member]
Common Stock Offering, Ownership Percentage Before Transaction					70.00%	70.00%
Proceeds from Issuance of Common Stock, Gross					$ 88,000,000	$ 88,000,000
Shares Issued, Price Per Share | $ / shares				$ 3	$ 0.15	$ 0.15
Proceeds from Issuance of Common Stock			$ 85,700,000
Stock Issued During Period, Shares, New Issues | shares			29,333,318
December Private Placement [Member] | Subsequent Event [Member]
Proceeds from Issuance of Common Stock, Gross	$ 100,000,000
Shares Issued, Price Per Share | $ / shares	$ 4.50
Proceeds from Issuance of Common Stock	$ 95,000,000
Stock Issued During Period, Shares, New Issues | shares	22,200,000
Common Stock, Par or Stated Value Per Share | $ / shares	$ 0.01
Other Expense [Member]
Termination Payment, Amount		$ 125,255
Series A Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage							15.00%
Preferred Stock, Par or Stated Value Per Share | $ / shares							$ 0.01
Preferred Stock, Purchase Price Per Share | shares							1,000
Preferred Stock, Original Issue Discount, Percentage							1.00%
Estimated Aggregate Gross Proceeds from Issuance of Preferred Stock							$ 6,300,000