Note 8 - Leases - Lease Expense and Other Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Amortization of right-of-use assets	$ 50	$ 0	$ 136	$ 0
Interest on finance lease liabilities	7	0	22	0
Finance lease expense	57	0	158	0
Operating lease expense	590	525	1,759	1,568
Short-term lease expense	0	0	0	6
Variable lease expense	67	43	204	155
Total lease expense	$ 714	$ 568	$ 2,121	$ 1,729
Operating leases (Year)	15 years 10 months 24 days	17 years 1 month 6 days	15 years 10 months 24 days	17 years 1 month 6 days
Financing leases (Year)	3 years 3 months 18 days		3 years 3 months 18 days
Operating leases	4.10%	4.10%	4.10%	4.10%
Financing leases	5.00%	0.00%	5.00%	0.00%
Right-of-use assets obtained in exchange for operating lease liabilities as of January 1, 2019	$ 603	$ 488	$ 1,739	$ 1,482
Operating cash flows from financing leases	$ 59	$ 0	$ 110	$ 0