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Regulatory Matters (Details Textual)	Dec. 31, 2016 USD ($)
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	0.625%
Minimum ratio of common equity tier 1 capital to risk-weighted assets, additional capital conservation buffer ratio	5.125%
Minimum ratio of tier 1 capital to risk-weighted assets, additional capital conservation buffer ratio	6.625%
Minimum ratio of total capital to risk-weighted assets, additional capital conservation buffer ratio	8.625%
Minimum leverage ratio, additional capital conservation buffer ratio	4.00%
Farmers National Banc Corp
Regulatory Matters (Additional Textual) [Abstract]
Minimum ratio of common equity tier 1 capital to risk-weighted assets, additional capital conservation buffer ratio	5.125%
Minimum ratio of tier 1 capital to risk-weighted assets, additional capital conservation buffer ratio	6.625%
Minimum ratio of total capital to risk-weighted assets, additional capital conservation buffer ratio	8.625%
Minimum leverage ratio, additional capital conservation buffer ratio	4.00%
Dividends that can be declared without prior approval	$ 1,900,000
Farmers Trust Company
Regulatory Matters (Additional Textual) [Abstract]
Minimum capital maintained by trust	3,000,000
Dividends that can be declared without prior approval	$ 102,000

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Capital conservation buffer ratio.

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Regulatory Matters (Additional Textual) [Abstract]

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Tier one leverage capital required for capital adequacy to average assets additional capital conservation buffer ratio.

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- Definition

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

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

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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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Minimum amount of net capital required to be maintained by the entity to engage in securities transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Rule 15c3-1
-Number 240
-Section 15c3-1

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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