Note 6 - Income Taxes (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred Income Tax Liabilities, Net, Total	$ 549	$ 818
Deferred Tax Assets, Valuation Allowance, Total	517	517
Unrecognized Tax Benefits, Ending Balance		0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	0	0
Liability for Uncertainty in Income Taxes, Current	$ 0	$ 0

Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount recognized for uncertainty in income taxes classified as current.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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