Note 21 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	34.00%	34.00%
Deferred Tax Assets, Net of Valuation Allowance, Total	$ 8,518	$ 7,179
Qualified Zone Academy Bonds	4,740	4,740
Unrecognized Tax Benefits, Ending Balance	0	988	$ 988
Income Tax Benefit from Accelerated Tax Depreciation Deduction	484
Domestic Tax Authority [Member] \| Internal Revenue Service (IRS) [Member]
Income Tax Examination, Liability (Refund) Adjustment from Settlement with Taxing Authority		(988)
Effective Income Tax Rate Reconciliation, Tax Settlement, Amount, Total	(988)
Capital Loss Carryforward [Member]
Tax Credit Carryforward, Amount	53	53
Other Assets [Member]
Qualified Zone Academy Bonds	4,700	4,700
Securities Available-for-sale [Member]
Qualified Zone Academy Bonds	$ 1,000	$ 1,000

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Carrying amount of Qualified Zone Academy Bonds.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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

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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of unrecognized tax benefits.

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