Note 13 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Beginning uncertain tax benefits	$ 1,951	$ 2,661
Prior year - increases (decreases)		(710)
Current year - increases (decreases)	0	0
Settlements	0	0
Expired statuses	(7)	0
Ending uncertain tax benefits	$ 1,944	$ 1,951

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 that have been or will be taken in current period tax return.

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

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