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Regulatory Matters (Details Textual) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
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Regulatory Matters (Additional Textual) [Abstract] |  |
Common equity tier 1 capital to risk-weighted assets, capital conservation buffer ratio | 2.50% |
Tier 1 capital to risk-weighted assets, capital conservation buffer ratio | 2.50% |
Total capital to risk-weighted assets, capital conservation buffer ratio | 2.50% |
Capital conservation buffer ratio | 2.50% | 2.50%
Capital conservation buffer, additional capital amount required | $ 52,900,000 | $ 47,800,000
Minimum ratio of common equity tier 1 capital to risk-weighted assets | 4.50% | 4.50%
Minimum ratio of tier 1 capital to risk-weighted assets | 0.060 | 0.060
Minimum ratio of total capital to risk-weighted assets | 0.080 | 0.080
Minimum leverage ratio | 0.040 | 0.040
Farmers National Banc Corp |  |
Regulatory Matters (Additional Textual) [Abstract] |  |
Minimum ratio of common equity tier 1 capital to risk-weighted assets | 4.50% | 4.50%
Minimum ratio of tier 1 capital to risk-weighted assets | 0.060 | 0.060
Minimum ratio of total capital to risk-weighted assets | 0.080 | 0.080
Minimum leverage ratio | 0.040 | 0.040
Dividends that can be declared without prior approval | $ 12,800,000 |
Farmers Trust Company |  |
Regulatory Matters (Additional Textual) [Abstract] |  |
Minimum capital maintained by trust | 3,000,000 |
Dividends that can be declared without prior approval | $ 206,000 |

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- Definition Tier one risk based capital required for capital adequacy to risk weighted assets capital conservation buffer ratio. + References No definition available. + Details
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- Definition Minimum amount of net capital required to be maintained by broker-dealer parent, calculated under Aggregate Indebtedness Standard. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Rule 15c3-1 -Number 240 -Section 15c3-1 + Details
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- Definition Ratio of minimum total risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958570-112826 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117337116&loc=SL5958568-112826 + Details
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