Note 12 - Income Taxes - Unrecognized Tax Benefits Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Balance	$ 20,491	$ 16,272	$ 14,431
Increase for tax position of prior year	1,589	1,474	169
Increase for tax position of current year	4,663	2,957	2,360
Decrease due to lapse of statute of limitation	(776)	(212)	(688)
Decrease due to settlement with tax authorities	(560)
Balance	$ 25,407	$ 20,491	$ 16,272

Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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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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