Note 8 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Unrecognized tax benefits at January 1	$ 8,234	$ 7,433
Additions for tax positions taken during prior periods	399	599
Additions for tax positions taken during current period including amended prior years	360	1,174
Reductions relating to settlements with taxing authorities	(2,227)
Reductions related to the expiration of statutes of limitations	(1,927)	(972)
Unrecognized tax benefits at December 31	$ 4,839	$ 8,234

Amount of unrecognized tax benefits.

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