Note 13 - Equity Incentive Plans - Vested Shares (Details) - USD ($)	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Number of options vested (in shares)	550,000	12,500
Fair value of options vested	$ 108,996	$ 2,834

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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 (c)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration