Note 10 - Income Taxes (Details Textual) - USD ($) |
12 Months Ended | |
---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
|
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount | $ 530,000 | $ 592,000 |
Liability for Uncertainty in Income Taxes, Current | $ 0 | $ 0 |
Open Tax Year | 2016 2017 2018 2019 2020 | |
Internal Revenue Service (IRS) [Member] | Domestic Tax Authority [Member] | ||
Operating Loss Carryforwards, Subject to Expiration | $ 57,500,000 | |
Operating Loss Carryforwards, Not Subject to Expiration | $ 7,600,000 |