Note 8 - Fair Values of Financial Instruments - Reconciliation for Assets Measured at Fair Value on Recurring Basis Using significant Unobservable Inputs (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Unrealized losses included in other comprehensive (loss) income		$ (632)
US States and Political Subdivisions Debt Securities [Member]
Balance	$ 22,114	18,516
Realized gains (losses) included in earnings	0	0
Unrealized losses included in other comprehensive (loss) income	(1,200)
Purchases	0	0
Sales	0	0
Maturities, prepayments, and calls	(4,840)	0
Transfers into level 3	0	0
Transfers out of level 3	(9,835)	0
Balance	6,239	$ 17,884
Corporate Debt Securities [Member]
Balance	488
Realized gains (losses) included in earnings	0
Unrealized losses included in other comprehensive (loss) income	(2)
Purchases	0
Sales	0
Maturities, prepayments, and calls	0
Transfers into level 3	0
Transfers out of level 3	0
Balance	$ 486

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-Subparagraph (c)(3)
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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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