Note 15 - Income Taxes - Liability Associated With Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Gross unrecognized tax benefits at beginning of year	$ 8,579	$ 547	$ 577
Increases related to prior year tax positions	75	8,190	94
Decreases related to prior year tax positions	0	0	0
Lapse of applicable statute of limitations	(139)	(158)	(124)
Gross unrecognized tax benefits at end of year	$ 8,515	$ 8,579	$ 547

Amount of unrecognized tax benefits.

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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 taken in prior period tax returns.

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