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Note 6 - Fair Value Measurements - Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Equity Securities [Member] |  |
Balance | $ 1,768 | $ 1,485
Total realized and unrealized gains included in income | (1) | (40)
Net purchases, sales, calls, and maturities | 0 | 500
Net transfers into Level 3 | 0 | 0
Balance | 1,767 | 1,945
Amount of total losses for the period included in earning attributable to the change in unrealized gains (losses) relating to assets and liabilities still held at March 31 | (1) | (40)
Net transfers into Level 3 | (0) | (0)
Available-for-Sale Securities [Member] |  |
Balance | 21,050 | 11,423
Net purchases, sales, calls, and maturities | 0 | 2,453
Net transfers into Level 3 | 0 | 0
Balance | 0 | 13,606
Amount of total losses for the period included in earning attributable to the change in unrealized gains (losses) relating to assets and liabilities still held at March 31 | 0 | (270)
Total unrealized gains included in other comprehensive income | 0 | (270)
Net transfers into Level 3 | 0 | 0
Transfer to held to maturity | $ (21,050) | $ 0

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- Definition Amount of transfers from one asset to held-to-maturity security 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 No definition available. + Details
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- Definition Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held. + 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 (d) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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- Definition Amount of gain (loss) recognized in income 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)(1) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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- Definition 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 + Details
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- Definition Amount of purchases, (sales), issuances and (settlements) 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 + Details
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- Definition 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) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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- Definition 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. + 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) -URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258 + Details
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