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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans, Average Investment and Interest Income (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Dec. 31, 2021
Average recorded investment in impaired loans(1) | [1] | $ 5,820 | $ 6,796 | $ 5,901
Interest income recognized on impaired loans, after designation as impaired |  | 43 | 105 | 137
Investor Owned Residential Real Estate [Member] | Consumer Real Estate Portfolio Segment [Member] |  |  |  |
Average recorded investment in impaired loans(1) | [1] | 189 | 193 | 192
Interest income recognized on impaired loans, after designation as impaired |  | 6 | 6 | 13
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Average recorded investment in impaired loans(1) | [1] | 2,626 | 2,890 | 2,668
Interest income recognized on impaired loans, after designation as impaired |  | 3 | 7 | 9
Commercial Real Estate Other [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Average recorded investment in impaired loans(1) | [1] | 2,719 | 3,378 | 2,723
Interest income recognized on impaired loans, after designation as impaired |  | 34 | 84 | 100
Commercial and Industrial [Member] | Commercial Non Real Estate Segment [Member] |  |  |  |
Average recorded investment in impaired loans(1) | [1] | 286 | 334 | 317
Interest income recognized on impaired loans, after designation as impaired |  | $ 0 | 8 | 15
Automobile Loan [Member] | Consumer Non Real Estate Portfolio Segment [Member] |  |  |  |
Average recorded investment in impaired loans(1) | [1] |  | 1 | 1
Interest income recognized on impaired loans, after designation as impaired |  |  | $ 0 | $ 0
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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