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Note 10 - Subordinated Debentures (Details Textual) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2021 USD ($) | Sep. 30, 2021 USD ($) | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2004 USD ($)
Repayments of Debt |  | $ 2,600,000 |  |  |
Proceeds of Debt Downstreamed |  | $ 5,000,000.0 |  |  |
Subordinated Debt [Member] |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  | 2.27% | 2.29% |
Subordinated Debt [Member] | Subordinated Notes Due 2031 [Member] |  |  |  |  |
Proceeds from Issuance of Subordinated Long-term Debt | $ 32,500,000 |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 3.25% | 3.25% |  |  |
Subordinated Debt [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  |  | 2.05% |  |
Subordinated Debt [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] | Subordinated Notes Due 2031 [Member] |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.55% |  |  |  |
Trust Preferred Securities [Member] |  |  |  |  |
Debt Securities, Available-for-sale, Number of Positions Sold |  |  |  |  | 4,500
Debt Securities, Available-for-sale, Price Per Position |  |  |  |  | 1,000

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- Definition Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6036836-161870 Reference 2: 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=124435984&loc=d3e28551-108399 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629 Reference 4: 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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