Note 11 - Financial Instruments - Summary of Derivative Fair Values (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Warrants, fair value	$ 1,397	$ 3,222
Warrants, volatility	169.16%
Financial Instrument Warrants [Member] \| Non-Current Liabilities [Member] \| Fair Value, Inputs, Level 3 [Member]
Warrants, fair value	$ 1,397	$ 3,222
Warrants, volatility	169.16%	104.70%

Fair value as of the balance sheet date of all price risk derivative liabilities not designated as hedging instruments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

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Period Type:	instant