Note 11 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Balance	$ 1,760	$ 1,747
Increase based on the tax positions in the current year	177	29
Increase for tax positions of prior year	157
Decrease for tax positions of prior year		(16)
Balance	$ 2,094	$ 1,760

Amount of unrecognized tax benefits.

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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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