Note 7 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unrecognized tax benefits	$ 1,563	$ 1,519	$ 707
Decreases related to prior year tax positions	(291)	(70)
Increases related to prior year tax positions	25		643
Increases related to current year tax positions	129	114	169
Unrecognized tax benefits	$ 1,426	$ 1,563	$ 1,519

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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