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Note 1 - Summary of Significant Accounting Policies (Details Textual) | 12 Months Ended
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Dec. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($) shares
Number of Branches | 16 |
Servicing Asset at Fair Value, Amount, Ending Balance | $ 105,900,000 | $ 92,300,000
Goodwill, Impairment Loss | 0 | 0
Mortgage Loans in Process of Foreclosure, Amount | $ 1,000,000.0 | $ 734,000
Treasury Stock, Shares, Ending Balance (in shares) | shares | 1,441,811 | 929,362
Treasury Stock, Shares, Acquired (in shares) | shares | 512,449 | 58,200
Core Deposits [Member] |  |
Finite-Lived Intangible Asset, Useful Life (Year) | 10 years |
Furniture and Fixtures [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |
Furniture and Fixtures [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 20 years |
Building and Building Improvements [Member] | Minimum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 3 years |
Building and Building Improvements [Member] | Maximum [Member] |  |
Property, Plant and Equipment, Useful Life (Year) | 40 years |

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