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Note 5 - Fair Value Measurements - Assets Measured on a Nonrecurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Impaired loans | $ 9,620 | $ 8,087
Fair Value, Nonrecurring [Member] |  |
Impaired loans | 5,390 | 4,111
Other real estate owned | 6,992 | 6,992
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member] |  |
Impaired loans | 0 | 0
Other real estate owned | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member] |  |
Impaired loans | 0 | 0
Other real estate owned | 0 | 0
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member] |  |
Impaired loans | 5,390 | 4,111
Other real estate owned | $ 6,992 | $ 6,992

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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 http://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524 + Details
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