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Note 1 - Summary of Significant Accounting Policies (Details Textual) |  | 12 Months Ended
--- | --- | ---
Dec. 01, 2022 USD ($) shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2021 USD ($) shares
Number of Branches |  | 22 |
Servicing Asset at Fair Value, Amount, Ending Balance |  | $ 94,800,000 | $ 105,900,000
Goodwill, Impairment Loss |  | 0 | 0
Mortgage Loans in Process of Foreclosure, Amount |  | 68,000 | 1,000,000.0
Other Real Estate, Ending Balance |  | 5,821,000 | 6,992,000
Impairment of Real Estate |  | $ 1,200,000 | $ 0
Treasury Stock, Shares, Total (in shares) | shares |  | 1,671,231 | 1,441,811
Treasury Stock, Shares, Acquired (in shares) | shares |  | 229,420 | 512,449
Commercial Real Estate Portfolio Segment [Member] |  |  |
Other Real Estate, Ending Balance |  | $ 5,800,000 | $ 7,000,000.0
Residential Portfolio Segment [Member] |  |  |
Other Real Estate, Ending Balance |  | $ 28,000 |
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 |
LBSI Insurance, LLC [Member] |  |  |
Business Acquisition, Percentage of Voting Interests Acquired |  | 100.00% |
Liberty Bancshares Inc [Member] |  |  |
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% |  |
Number of Branches | 6 |  |
Business Combination, Amount Shares Issued to Acquiree's Shareholders Per Share (in shares) | shares | 2.752 |  |
Stock Issued During Period, Shares, Acquisitions (in shares) | shares | 2,600,000 |  |
Business Combination, Consideration Transferred, Total | $ 73,265,000 |  |
Goodwill, Impairment Loss |  | $ 0 |
Liberty Bancshares Inc [Member] | Core Deposits [Member] |  |  |
Finite-Lived Intangible Asset, Useful Life (Year) | 10 years |  |

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