v3.8.0.1

Note 18 - Income Taxes (Details Textual) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Income Tax Expense (Benefit) |  |  | $ (701,000) | $ (34,000) | $ 760,000
Valuation Allowances and Reserves, Period Increase (Decrease) |  |  | (17,100,000) | 14,200,000 | $ 5,500,000
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax |  |  |  | $ 703,000 |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  |  | 35.00% |  |
Tax Adjustments, Settlements, and Unusual Provisions | (700,000) |  |  |  |
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability | 0 |  |  |  |
Earliest Tax Year [Member] |  |  |  |  |
Open Tax Year |  |  | 2005 |  |
Latest Tax Year [Member] |  |  |  |  |
Open Tax Year |  |  | 2017 |  |
Subject to Expiration [Member] |  |  |  |  |
Operating Loss Carryforwards | 1,400,000 |  | $ 1,400,000 |  |
Scenario, Forecast [Member] |  |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent |  | 21.00% |  |  |
Research Tax Credit Carryforward [Member] | Subject to Expiration [Member] |  |  |  |  |
Tax Credit Carryforward, Amount | 26,000 |  | 26,000 |  |
Domestic Tax Authority [Member] |  |  |  |  |
Operating Loss Carryforwards | 115,600,000 |  | 115,600,000 |  |
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax | 700,000 |  | 700,000 |  |
Domestic Tax Authority [Member] | Accounting Standards Update 2016-09 [Member] |  |  |  |  |
Operating Loss Carryforwards | 2,900,000 |  | 2,900,000 |  |
Domestic Tax Authority [Member] | Research Tax Credit Carryforward [Member] |  |  |  |  |
Tax Credit Carryforward, Amount | 5,900,000 |  | 5,900,000 |  |
State and Local Jurisdiction [Member] |  |  |  |  |
Operating Loss Carryforwards | 97,200,000 |  | 97,200,000 |  |
State and Local Jurisdiction [Member] | Accounting Standards Update 2016-09 [Member] |  |  |  |  |
Operating Loss Carryforwards | 2,000,000 |  | 2,000,000 |  |
State and Local Jurisdiction [Member] | Research Tax Credit Carryforward [Member] |  |  |  |  |
Tax Credit Carryforward, Amount | $ 3,600,000 |  | $ 3,600,000 |  |

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