Regulatory Capital Matters (Details Textual)	Sep. 30, 2024	Dec. 31, 2023
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%
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	0.06	0.06
Minimum ratio of total capital to risk-weighted assets	0.08	0.08
Minimum leverage ratio	0.04	0.04
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	0.06	0.06
Minimum ratio of total capital to risk-weighted assets	0.08	0.08
Minimum leverage ratio	0.04	0.04

Capital required for capital adequacy to risk weighted assets capital conservation buffer ratio.

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Regulatory Matters (Additional Textual) [Abstract]

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Tier one risk based capital required for capital adequacy to risk weighted assets capital conservation buffer ratio.

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Tier one risk based common capital required for capital adequacy to risk weighted assets.

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Tier one risk based common capital required for capital adequacy to risk weighted assets capital conservation buffer ratio.

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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
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477270/942-505-50-1B

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Ratio of minimum Tier 1 leverage capital to average assets required for capital adequacy as defined by regulatory framework.

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Ratio of minimum Tier 1 risk-based capital to risk-weighted assets required for capital adequacy as defined by regulatory framework.

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