Note 3 - Financial Condition and Business Plan (Details Textual) - USD ($)				1 Months Ended	9 Months Ended	28 Months Ended	55 Months Ended
	Oct. 27, 2017	Oct. 04, 2017	Oct. 02, 2015	Oct. 31, 2017	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2017	Jun. 26, 2017	Jun. 09, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Retained Earnings (Accumulated Deficit)					$ (257,101,046)	$ (257,101,046)	$ (257,101,046)			$ (241,379,712)
Cash and Cash Equivalents, at Carrying Value					$ 2,685,010	$ 2,685,010	$ 2,685,010			$ 2,624,162	$ 4,184,222	$ 9,265,144
Class of Warrant or Right, Exercise Price of Warrants or Rights					$ 5.33	$ 5.33	$ 5.33	$ 1.65	$ 2.70	$ 9.39
Class of Warrant or Right, Issued During Period					6,679,378
Proceeds from Warrant Exercises						$ 800,000	$ 2,100,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights								506,627	790,410
Aggregate Offering Price, Additions			$ 7,500,000
Subsequent Event [Member]
Proceeds from Issuance of Common Stock and Warrant Exercises				$ 23,600,000
Subsequent Event [Member] | October 2017 Exercise Agreements [Member]
Stock Issued During Period, Shares, Additional Exercise of Warrants		300,000
Proceeds from Warrant Exercises		$ 17,000,000
Subsequent Event [Member] | October 2017 Exercise Agreements [Member] | Series AAA and Series BBB Warrants [Member]
Class of Warrant or Right, Exercised During Period		4,665,000
Proceeds from Warrant Exercises		$ 20,000,000
Subsequent Event [Member] | October 2017 Exercise Agreements [Member] | Series AAA Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 2.07
Subsequent Event [Member] | October 2017 Exercise Agreements [Member] | Series BBB Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights		4.75
Subsequent Event [Member] | October 2017 Exercise Agreements [Member] | Series DDD Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 6.20
Class of Warrant or Right, Issued During Period		1,166,250
Subsequent Event [Member] | October 2017 Undwriting Offering [Member]
Stock Issued During Period, Shares, New Issues	2,640,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights	1,300,000
Proceeds from Issuance of Common Stock and Warrants	$ 6,600,000