Note 11 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Gross unrecognized tax benefits	$ 13,292	$ 12,889
Increases in tax positions for current year	667	664
Increases in tax positions for prior years	1
Lapse in statute of limitations	(345)	(261)
Gross unrecognized tax benefits	$ 13,615	$ 13,292

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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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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