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Note 18 - Fair Value Disclosure Measurements (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2006 | Dec. 31, 2021 | Dec. 31, 2020
Estimated Selling Costs of Impaired Loans |  | $ 901,000 | $ 838,000
Mandatorily Redeemable Securities |  | $ 8,000,000.0 |
London Interbank Offered Rate (LIBOR) [Member] |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.67% |  |
Notes Payable, Other Payables [Member] | London Interbank Offered Rate (LIBOR) [Member] |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 1.67% |
Other Borrowings [Member] |  |  |
Notes Payable, Total |  | $ 8,300,000 |

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