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Note 8 - Subordinated Debt (Details Textual) - USD ($) $ in Thousands | Jun. 29, 2020 | Mar. 31, 2021 | Dec. 31, 2020 | Oct. 30, 2015
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Subordinated Loan Agreement Note [Member] |  |  |  |
Debt Instrument, Face Amount |  |  |  | $ 5,000
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 6.75%
Subordinated Term Note Due 2030 [Member] |  |  |  |
Debt Instrument, Face Amount | $ 5,000 |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.50% |  |  |
Debt Issuance Costs, Net, Total |  | $ 8 | $ 9 |
Subordinated Term Note Due 2030 [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 5.10% |  |  |

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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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