Note 11 - Income Taxes (Details Textual)	12 Months Ended
Dec. 31, 2019 USD ($)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Operating Loss Carryforwards, Total	$ 24,948,000
Open Tax Year	2019 2018 2017

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Topic 740
-SubTopic 10
-Section S99
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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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