Note 14 - Income Taxes - Liability Associated With Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gross unrecognized tax benefits at beginning of year	$ 547	$ 577	$ 488
Increases related to prior year tax positions	8,190	94	156
Decreases related to prior year tax positions
Lapse of applicable statute of limitations	(158)	(124)	(67)
Gross unrecognized tax benefits at end of year	$ 8,579	$ 547	$ 577

Amount of unrecognized tax benefits.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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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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-Publisher FASB
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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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