Note 13 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Unrecognized tax benefits - January 1	$ 3,276	$ 1,968	$ 8,777
Gross decreases - tax positions in a prior period	0	0	(8,422)
Gross increases - tax positions in a current period	985	1,308	1,613
Unrecognized tax benefits - December 31	$ 4,261	$ 3,276	$ 1,968