Note 5 - Leases -Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Weighted average remaining lease term (years) (Year)	4 years 5 months 8 days		4 years 5 months 8 days
Weighted average discount rates	1.99%		1.99%
Operating lease cost	$ 758	$ 634	$ 1,499	$ 1,231
Cash payments for operating leases	$ 799	$ 752	$ 1,598	$ 1,345

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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-Publisher FASB
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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
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Weighted average discount rate for operating lease calculated at point in time.

+ References

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-Publisher FASB
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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
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