Note 7 - Leases (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 01, 2019
Operating Lease, Right-of-Use Asset	$ 3,719	$ 2,863
Lessee, Operating Lease, Lease Not yet Commenced, Future Lease Obligations	4,600
Operating Lease, Lease Income, Lease Payments	1,900	1,800
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset			$ 2,300
Other Assets [Member]
Operating Lease, Right-of-Use Asset	3,700	2,900
Other Liabilities [Member]
Operating Lease, Liability, Total	$ 3,100	$ 2,400
Maximum [Member]
Lessee, Operating Lease, Renewal Term (Year)	2 years
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract (Year)	4 years
Lessor, Operating Lease, Remaining Lease Term (Year)	4 years
Lessor, Operating Lease, Renewal Term (Year)	5 years
Minimum [Member]
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract (Year)	1 year
Lessor, Operating Lease, Remaining Lease Term (Year)	2 years