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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, 2022 | Dec. 31, 2021
Loans past due 90 days or more and still accruing | [1] | $ 8 | $ 90
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% | 0.01%
Accruing TDR loans |  | $ 276 | $ 3,005
Impaired loans: |  |  |
Impaired loans with no valuation allowance | [2] | 3,032 | 5,878
Impaired loans with a valuation allowance | [2] | 0 | 0
Total impaired loans | [2],[3] | 3,032 | 5,878
Valuation allowance | [2] | 0 | 0
Impaired loans, net of allowance |  | 3,032 | 5,878
Average recorded investment in impaired loans(1) | [3] | 3,047 | 5,901
Income recognized on impaired loans, after designation as impaired | [2] | 18 | 137
Amount of income recognized on a cash basis |  | $ 0 | $ 0
[1] | Only classes with past due or nonaccrual loans are presented.
[2] | Only classes with impaired loans are shown.
[3] | 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 The amount of average recorded investment from impaired financing receivable, net of charge-offs and interest paid. + 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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- Definition Represents ratio of loans past due 90 days or more and still accruing to loans, net of unearned income and deferred fees. + References No definition available. + Details
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- Definition Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 80 -URI https://asc.fasb.org/extlink&oid=124267575&loc=SL82922355-210448 + Details
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- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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)(2) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
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- Definition Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + 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)(3) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524 + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + 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 (a)(3) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
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