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Note 3 - Loans and Allowance for Loan Losses (Details Textual) | 3 Months Ended
--- | ---
Mar. 31, 2021 USD ($) | Mar. 31, 2020 USD ($)
Provision for Loan, Lease, and Other Losses, Total | $ 250,000 | $ 775,000
Financing Receivable, Modifications, Number of Contracts | 7 | 0
Financing Receivable, Number of Payment Deferrals | 17 |
Financing Receivable, Deferred Payments | $ 1,200,000 |
Financing Receivable, Deferred Payments, Remained Active | $ 1,200,000 |
Maximum [Member] |  |
Financing Receivable, Number of Payment Deferrals, Remained Active | 17 |

X
- Definition Deferred amounts on loans receivable related to loan modification programs offered to financial institution customers affected by COVID-19. + References No definition available. + Details
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- Definition The outstanding balance of deferred payment loan that remained active. + References No definition available. + Details
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- Definition Number of principal and interest payment deferrals on loans receivable related to loan modification programs offered to financial institution customers affected by COVID-19. + References No definition available. + Details
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- Definition Number of payment deferral loans that remained active. + References No definition available. + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
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- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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