Note 12 - Stock Based Compensation - Valuation Assumptions (Details) - $ / shares		6 Months Ended
Jan. 13, 2019	Jun. 30, 2019
Liability Options [Member]
Stock price (in dollars per share)	$ 1.36
Minimum [Member] \| Liability Options [Member]
Risk free interest rate	2.53%
Minimum [Member] \| Share-based Payment Arrangement, Option [Member]
Expected volatility		107126.00%
Maximum [Member] \| Share-based Payment Arrangement, Option [Member]
Expected volatility		109126.00%

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

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