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Employee Benefit Plans (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items] |  |  |
The accrued postretirement benefit liability due to termination of plan | $ 0 | $ 0 |
National Bancshares Corporation |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | 136,000 | (19,000) | $ (91,000)
Liability under the Plan | $ 1,000,000 | 941,000 |
Director age for eligibility for annual retirement benefit plan | 70 years |  |
Maximum years for benefit payment under the plan | 15 years |  |
Retirement Savings Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employees who have completed no days of service | 90 days |  |
Percentage of matching contribution by company | 50.00% |  |
(Benefit) expense under the plan | $ 708,000 | 573,000 | 556,000
Retirement Savings Plan | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of the participants' voluntary contributions of gross wages | 6.00% |  |
Profit Sharing Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | $ 95,000 | $ 78,000 | $ 105,000
Annual compensation for associates, Percent | 1.00% | 1.00% | 1.00%
Deferred Compensation Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | $ 7,000 | $ 8,000 | $ 8,000
Liability under the Plan | 115,000 | 124,000 |
Deferred compensation plan asset recorded | 1,300,000 | 753,000 | 566,000
Deferred compensation plan liability recorded | $ 1,300,000 | $ 753,000 | 566,000
Defined Benefit Postretirement Health Coverage |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan |  |  | $ (70,000)

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- Definition The carrying amount of the liability as of the balance sheet date to an individual under a deferred compensation arrangement. This amount may be the result of periodic accruals made over the period of active employment, or reflect termination benefits resulting contractual terms or a death benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 30 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6409875&loc=d3e20015-108363 + Details
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