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Note 8 - Employee Benefit Plans (Details Textual) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent | 100.00% |  |
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ 394 | $ 379 | $ 364
Age Attained to be Eligible for ESOP (Year) | 21 years |  |
Employee Stock Ownership Plan (ESOP), Cash Contributions to ESOP | $ 300 | 300 | 300
Employee Stock Ownership Plan (ESOP), Number of Allocated Shares (in shares) | 184,503 |  |
Age of Employees Required to Diversify Allocated ESOP Shares (Year) | 55 years |  |
Years of Plan Participation Required to Diversify Allocated ESOP Shares (Year) | 10 years |  |
Percentage of Allocated ESOP Shares That Can be Diversified | 50.00% |  |
Accrued Expenses for Salary Continuation Plan | $ 304 | $ 270 | $ 255
Equity Securities [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 65.00% |  |
Fixed Income Securities [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 35.00% |  |
Hedge Funds [Member] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 0.00% |  |

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- Definition Liability for agreement to continue an employee's salary after termination of employment including retirement, death, disability, or other event. For example, a company may agree to continue a disabled employee's salary for six months. + References No definition available. + Details
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- Definition Age of an employee to be eligible for the Employee Stock Ownership Plan (ESOP). + References No definition available. + Details
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- Definition Age required to diversify allocated Employee Stock Ownership Plan (ESOP) shares. + References No definition available. + Details
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- Definition Percentage of allocated Employee Stock Ownership Plan shares that can diversified. + References No definition available. + Details
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- Definition Years of plan participation required to diversify Employee Stock Ownership Plan (ESOP). + References No definition available. + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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- Definition This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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- Definition The shares or units in an ESOP trust that have been assigned to individual participant accounts based on a known formula. IRS rules require allocations to be nondiscriminatory generally based on compensation, length of service, or a combination of both. For any particular participant such shares or units may be vested, unvested, or partially vested. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109244661&loc=d3e17540-113929 + Details
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