Note 1 - Basis of Presentation (Details Textual) - USD ($)	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Effective Income Tax Rate Reconciliation, Percent, Total	23.80%	35.80%
Unrecognized Tax Benefits, Period Increase (Decrease), Total	$ (9,000)
Unrecognized Tax Benefits, Ending Balance	158,000
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ (40,000)

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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