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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans Past Due 90 Days or More and Impaired Loans (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Loans past due 90 days or more and still accruing |  | $ 90 | $ 17
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees and costs |  | 0.01% | 0.00%
Accruing TDR loans |  | $ 3,005 | $ 1,410
Impaired loans: |  |  |
Impaired loans with no valuation allowance | [1] | 5,878 | 3,858
Impaired loans with a valuation allowance | [1] | 0 | 1,045
Total impaired loans | [1] | 5,878 | 4,903
Valuation allowance |  | 0 | (75)
Impaired loans, net of allowance |  | 5,878 | 4,828
Average recorded investment in impaired loans(1) | [1] | 5,901 | 5,093
Income recognized on impaired loans, after designation as impaired |  | $ 137 | $ 54
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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- Definition Reflects the carrying amount of loans modified in a troubled debt restructuring that are accruing interest. + References No definition available. + Details
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- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses, net of allowance. + References No definition available. + Details
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