Note 3 - Basis of Presentation and Summary of Significant Accounting Policies (Details Textual) - USD ($)	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Goodwill, Ending Balance	$ 6,929,258		$ 6,929,258
Impairment of Intangible Assets (Excluding Goodwill), Total	0	$ 0
Goodwill, Impairment Loss	0	$ 0
RES-529 [Member]
Intangible Assets, Net (Excluding Goodwill), Total	8,600,000
Convertible Note, Series B [Member]
Convertible Debt, Total	$ 600,000		600,000
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Debt Instrument, Convertible, Conversion Price	$ 2.74
Convertible Note, Series B [Member] \| Accrued Expenses and Other Current Liabilities [Member]
Interest Payable	$ 38,000
Fair Value, Inputs, Level 3 [Member] \| Convertible Note, Series B [Member]
Convertible Debt, Fair Value Disclosures	$ 600,000		$ 600,000

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

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