Note 1 - Nature of Operations (Details Textual)		12 Months Ended
Jun. 20, 2017	Dec. 31, 2018
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	10	10

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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