Note 13 - Income Taxes - Uncertain Tax Positions (Details)	12 Months Ended
Dec. 31, 2018 USD ($)
Balance
Settlement/decreases related to tax positions taken during prior years
Increases related to tax positions taken during prior years	372
Increases related to tax positions taken during the current year
Balance	$ 372

Amount of unrecognized tax benefits.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 45
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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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