Note 13 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Unrecognized tax benefit, beginning of period	$ 7,122	$ 7,943
Increase in unrecognized tax benefit for positions taken in current period	580	251
Statute of limitation expirations	(1,818)	(1,072)
Settlements	(249)
Unrecognized tax benefit, end of period	$ 5,635	$ 7,122