Note 4 - Leases -Lease Cost (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Weighted average remaining lease term (years) (Year)	4 years 11 months 23 days		4 years 11 months 23 days
Weighted average discount rates	1.97%		1.97%
Operating lease cost	$ 843	$ 758	$ 1,643	$ 1,499
Cash payments for operating leases	$ 786	$ 799	$ 1,616	$ 1,598

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
-Name Accounting Standards Codification
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-Section 55
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-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(4)
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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 53
-URI https://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

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