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Note 18 - Fair Value Disclosure Measurements - Assets Measured on a Recurring Basis (Details) - USD ($) | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Total debt securities | $ 105,733,000 | $ 98,322,000
Equity securities in financial institutions | 710,000 | 616,000
Subordinated Debt Securities [Member] |  |
Total debt securities | 4,126,000 |
US Government Agencies Debt Securities [Member] |  |
Total debt securities |  | 7,471,000
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 18,630,000 | 17,758,000
Fair Value, Recurring [Member] |  |
Total debt securities | 105,733,000 | 98,322,000
Equity securities in financial institutions | 710,000 | 616,000
Total | 106,443,000 | 98,938,000
Fair Value, Recurring [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 4,126,000 |
Fair Value, Recurring [Member] | US Government Agencies Debt Securities [Member] |  |
Assets measured on a recurring basis |  | 7,471,000
Fair Value, Recurring [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 82,977,000 | 73,093,000
Fair Value, Recurring [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 18,630,000 | 17,758,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |  |
Total debt securities |  |
Equity securities in financial institutions | 710,000 | 616,000
Total | 710,000 | 616,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member] |  |
Assets measured on a recurring basis |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |  |
Total debt securities | 105,733,000 | 98,322,000
Equity securities in financial institutions |  |
Total | 105,733,000 | 98,322,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities | 4,126,000 |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member] |  |
Assets measured on a recurring basis |  | 7,471,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities | 82,977,000 | 73,093,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities | 18,630,000 | 17,758,000
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |  |
Total debt securities |  |
Equity securities in financial institutions |  |
Total |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Subordinated Debt Securities [Member] |  |
Total debt securities |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member] |  |
Assets measured on a recurring basis |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | US States and Political Subdivisions Debt Securities [Member] |  |
Total debt securities |  |
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member] |  |
Total debt securities |  |

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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