Note 3 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net Income (Loss) Attributable to Parent, Total	$ (2,953)	$ (2,087)	$ (12,888)	$ (3,963)
Net Income (Loss) Excluding Non-cash Impairment, Change in Warrant Liabilities, Share Based Payment, Allowance for Doubtful Accounts and Deferred Taxes			(5,900)
Net Cash Provided by (Used in) Operating Activities, Total			(3,693)	$ (2,654)
Contract with Customer, Asset, Net, Total	0		0
Contract with Customer, Performance Obligation Satisfied in Previous Period	0		0
Goodwill and Intangible Asset Impairment, Total	1,500		$ 8,700
Advertising Expense	$ 0