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Note 14 - Income Taxes (Details Textual)

v3.19.1

Note 14 - Income Taxes (Details Textual) - USD ($) $ in Thousands	Jan. 01, 2018	Dec. 22, 2017	Mar. 31, 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%	50.00%
Unrecognized Tax Benefits, Ending Balance			$ 0	$ 0
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards, Total			130,900
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount			8,700
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total			20,300
Other Noncurrent Assets [Member]
Deferred Tax Assets, Tax Credit Carryforwards, Alternative Minimum Tax			$ 1,200	$ 1,200

- 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).

+ References

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- Definition

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

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