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Note 18 - Fair Value Measurements - Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Acquisition |  | $ 2,756,000
Equity Securities [Member] |  |
Balance | $ 1,472,000 | 886,000
Total realized and unrealized gains included in income | 13,000 | 114,000
Net purchases, sales, calls, and maturities | 0 | 0
Net transfers into Level 3 | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Acquisition | 0 | 472,000
Balance, December 31 | 1,485,000 | 1,472,000
Available-for-sale Securities [Member] |  |
Balance | 12,367,000 | 8,498,000
Total realized and unrealized gains included in income | 0 | 0
Net purchases, sales, calls, and maturities | (1,456,000) | 1,375,000
Net transfers into Level 3 | 0 | 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Acquisition | 0 | 2,284,000
Balance, December 31 | 11,423,000 | 12,367,000
Total unrealized gains/(losses) included in other comprehensive income | $ 512,000 | $ 210,000

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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 http://asc.fasb.org/extlink&oid=117815213&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 http://asc.fasb.org/extlink&oid=117815213&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 http://asc.fasb.org/extlink&oid=117815213&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 http://asc.fasb.org/extlink&oid=117815213&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 http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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