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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans, Average Investment and Interest Income (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
Average recorded investment in impaired loans(1) | [1] | $ 5,901 | $ 5,093
Interest income recognized |  | 137 | 54
Investor Owned Residential Real Estate [Member] | Consumer Real Estate Portfolio Segment [Member] |  |  |
Average recorded investment in impaired loans(1) | [1],[2] | 192 | 196
Interest income recognized | [2] | 13 | 13
Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Average recorded investment in impaired loans(1) | [1],[2] | 2,668 | 3,217
Interest income recognized | [2] | 9 | 19
Commercial Real Estate Other [Member] | Commercial Real Estate Portfolio Segment [Member] |  |  |
Average recorded investment in impaired loans(1) | [1],[2] | 2,723 | 790
Interest income recognized | [2] | 100 | 0
Commercial and Industrial [Member] | Commercial Non Real Estate Segment [Member] |  |  |
Average recorded investment in impaired loans(1) | [1],[2] | 317 | 887
Interest income recognized | [2] | 15 | 22
Automobile Loan [Member] | Consumer Non Real Estate Portfolio Segment [Member] |  |  |
Average recorded investment in impaired loans(1) | [1],[2] | $ 1 | $ 3
[1] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[2] | Only classes with impaired loans are shown.

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- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524 + Details
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