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Note 5 - Allowance for Loan Losses on Loans and Nonperforming Assets - Impaired Loans, Average Investment and Interest Income (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 USD ($)
Average recorded investment | $ 3,776 | [1]
Interest income recognized | 18 |
Investor Owned Residential Real Estate [Member] | Consumer Real Estate Portfolio Segment [Member] |  |
Average recorded investment | 188 | [1]
Interest income recognized | 13 |
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] |  |
Average recorded investment | 2,587 | [1]
Interest income recognized | 5 |
Commercial Real Estate Other [Member] | Commercial Real Estate Portfolio Segment [Member] |  |
Average recorded investment | 729 |
Interest income recognized | 0 |
Commercial and Industrial [Member] | Commercial Non Real Estate Segment [Member] |  |
Average recorded investment | 272 | [1]
Interest income recognized | $ 0 |
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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