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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans Past Due 90 Days or More and Impaired Loans (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Loans past due 90 days or more and still accruing |  | $ 28 | [1] | $ 237 | $ 17 | [1]
Ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees and costs |  | 0.00% |  | 0.03% | 0.00% |
Accruing restructured loans |  | $ 3,011 |  | $ 1,453 | $ 1,410 |
Impaired loans: |  |  |  |  |  |
Impaired loans with no valuation allowance |  | 6,774 | [2] | 4,151 | 3,858 | [2]
Impaired loans with a valuation allowance |  | 0 | [2] | 1,076 | 1,045 | [2]
Total impaired loans |  | 6,774 | [2] | 5,227 | 4,903 | [2]
Valuation allowance |  | 0 |  | (104) | (75) |
Impaired loans, net of allowance |  | 6,774 |  | 5,123 | 4,828 |
Average recorded investment in impaired loans(1) | [2] | 6,796 |  | 5,263 | 5,093 |
Interest income recognized on impaired loans, after designation as impaired |  | $ 105 |  | $ 29 | $ 54 |
[1] | Only classes with past-due or nonaccrual loans are shown.
[2] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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