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Employee Benefit Plans (Details Textual) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items] |  |  |
The accrued postretirement benefit liability due to termination of plan | $ 0 | $ 70,000 |
Defined Benefit Postretirement Health Coverage |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | (70,000) | (184,000) | $ (12,000)
National Bancshares Corporation |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | 91,000 | 130,000 | 0
Liability under the Plan | $ 1,000,000 | 1,000,000 |
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 the participants' voluntary contributions of gross wages | 6.00% |  |
(Benefit) expense under the plan | $ 556,000 | 506,000 | 431,000
Profit Sharing Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
(Benefit) expense under the plan | $ 103,000 | $ 103,000 | $ 82,000
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 | $ 8,000 | $ 9,000 | $ 10,000
Liability under the Plan | 133,000 | 141,000 |
Deferred compensation plan asset recorded | 566,000 | 345,000 | 67,000
Deferred compensation plan liability recorded | 566,000 | 345,000 | $ 67,000
ESOP | Tri-State 1st Banc Incorporation |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to the plan | $ 0 | $ 0 |
Shares held in trust | 0 | 39,690 |

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- Definition Number of common stock held in a trust that has been set up specifically to accumulate stock for the sole purpose of distribution to participating employees but not yet earned. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 40 -Section 25 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=65888597&loc=d3e16701-113920 + Details
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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://www.xbrl.org/2003/role/presentationRef -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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- Definition Amount of liability, recognized in statement of financial position, for defined benefit other postretirement plan. Excludes pension plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(15)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(15)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 + Details
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