Note 15 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Unrecognized tax benefit, beginning of period	$ 5,635	$ 7,122
Increase in unrecognized tax benefit for positions taken in prior period	633	0
Increase in unrecognized tax benefit for positions taken in current period	495	580
Statute of limitation expirations	(43)	(1,818)
Settlements	0	(249)
Unrecognized tax benefit, end of period	$ 6,720	$ 5,635

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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