Note 12 - Income Taxes - Unrecognized Tax Benefits Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance	$ 16,272	$ 14,431	$ 12,093
Increase for tax position of prior year	1,474	169	243
Increase for tax position of current year	2,957	2,360	2,095
Decrease due to lapse of statute of limitation	(212)	(688)
Balance	$ 20,491	$ 16,272	$ 14,431

Amount of unrecognized tax benefits.

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-Name Accounting Standards Codification
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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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