Note 7 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Unrecognized tax benefits	$ 1,519	$ 707	$ 651
Decreases related to prior year tax positions	(70)
Increases related to prior year tax positions		643
Increases related to current year tax positions	114	169	56
Unrecognized tax benefits	$ 1,563	$ 1,519	$ 707

Amount of unrecognized tax benefits.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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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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