Note 6 - Leases - Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Operating lease cost	$ 221	$ 212	$ 660	$ 636
Short-term lease cost	42	26	113	86
Sublease income	(19)	(17)	(56)	(32)
Total lease cost	244	221	717	690
Operating cash flows from operating leases	$ 238	$ 225	$ 709	$ 674