Regulatory Capital Matters (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Common equity tier 1 capital ratio
Actual, Amount	$ 374,278	$ 403,307
Actual, Ratio	10.25%	13.71%
Requirement for Capital Adequacy Purposes, Amount	$ 164,288	$ 132,349
Requirement for Capital Adequacy Purposes, Ratio	4.50%	4.50%
Total risk based capital ratio
Actual, Amount	$ 502,235	$ 523,285
Actual, Ratio	0.1376	0.1779
Requirement for Capital Adequacy Purposes, Amount	$ 292,068	$ 235,288
Requirement for Capital Adequacy Purposes, Ratio	0.080	0.080
Tier 1 risk based capital ratio
Actual, Amount	$ 392,278	$ 421,307
Actual, Ratio	0.1074	0.1432
Requirement for Capital Adequacy Purposes, Amount	$ 219,051	$ 176,466
Requirement for Capital Adequacy Purposes, Ratio	0.060	0.060
Tier 1 leverage ratio
Actual, Amount	$ 392,278	$ 421,307
Actual, Ratio	0.0768	0.0984
Requirement for Capital Adequacy Purposes, Amount	$ 204,281	$ 171,233
Requirement for Capital Adequacy Purposes, Ratio	0.040	0.040
Farmers National Banc Corp
Common equity tier 1 capital ratio
Actual, Amount	$ 391,584	$ 372,679
Actual, Ratio	10.75%	12.71%
Requirement for Capital Adequacy Purposes, Amount	$ 163,977	$ 131,968
Requirement for Capital Adequacy Purposes, Ratio	4.50%	4.50%
To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 236,855	$ 190,620
To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%	6.50%
Total risk based capital ratio
Actual, Amount	$ 426,541	$ 399,657
Actual, Ratio	0.1171	0.1362
Requirement for Capital Adequacy Purposes, Amount	$ 291,514	$ 234,609
Requirement for Capital Adequacy Purposes, Ratio	0.080	0.080
To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 364,393	$ 293,262
To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.10	0.100
Tier 1 risk based capital ratio
Actual, Amount	$ 391,584	$ 372,679
Actual, Ratio	0.1075	0.1271
Requirement for Capital Adequacy Purposes, Amount	$ 218,636	$ 175,957
Requirement for Capital Adequacy Purposes, Ratio	0.060	0.060
To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 291,514	$ 234,609
To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.08	0.080
Tier 1 leverage ratio
Actual, Amount	$ 391,584	$ 372,679
Actual, Ratio	0.077	0.0876
Requirement for Capital Adequacy Purposes, Amount	$ 203,408	$ 170,245
Requirement for Capital Adequacy Purposes, Ratio	0.040	0.040
To be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 254,261	$ 212,807
To be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	0.05	0.05

Tier one common capital.

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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 to be well capitalized.

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Amount of total capital as defined by regulatory framework.

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Amount of minimum total risk-based capital required for capital adequacy as defined by regulatory framework.

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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//1943274/2147480696/942-505-50-1

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//1943274/2147480696/942-505-50-1B

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