Note 8 - Income Taxes - Unrecognized Tax Benefits Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance	$ 1,796	$ 1,924	$ 2,051
Increases related to prior year tax positions	2,969	4	19
Decreases related to prior year positions		(9)	(10)
Increases related to current year tax positions	287
Decreases related to settlements with taxing authorities	(4,200)
Decreases related to lapsing of statute of limitations	(29)	(123)	(136)
Balance	$ 823	$ 1,796	$ 1,924

Amount of unrecognized tax benefits.

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