Quarterly report pursuant to Section 13 or 15(d)

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Note 14 - Income Taxes (Details Textual)

v3.19.3

Note 14 - Income Taxes (Details Textual) - USD ($)			9 Months Ended
Note 14 - Income Taxes (Details Textual) - USD ($)	Jan. 01, 2018	Dec. 22, 2017	Sep. 30, 2019	Dec. 31, 2018
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	35.00%
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax, Percentage Reclassified to Income Tax Receivable				50.00%
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax				$ 1,200,000
Proceeds from Income Tax Refunds			$ 621,000
Income Taxes Receivable, Noncurrent			621,000
Unrecognized Tax Benefits, Ending Balance			0	$ 0
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards, Total			130,900,000
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount			8,700,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total			$ 20,300,000

- Definition

Represents the percentage of deferred tax assets related to AMT tax credit carryforwards, which percentage was reclassified to income tax receivable (included in prepaid and other current assets).

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible alternative minimum tax credit carryforwards.

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

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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