Note 5 - Leases - Leases Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Operating lease costs	$ 623	$ 364	$ 1,694	$ 1,093
Other	140	87	387	235
Total lease costs	763	451	2,081	1,328
Operating cash flows from operating leases	612	394	1,622	1,097
ROU assets obtained in exchange for new operating lease liabilities	$ 793	$ 0	$ 4,477	$ 1,796
Weighted-average remaining lease term (in years) (Year)	3 years		3 years		2 years 8 months 12 days
Weighted-average discount rate	2.10%		2.10%		2.70%