Summary of Significant Accounting Policies (Policies)	9 Months Ended
Sep. 30, 2019
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation: Farmers National Banc Corp. (“Company”) is a Financial Holding Company registered under the Bank Holding Company Act of 1956, as amended. The Company provides full banking services through its nationally chartered subsidiary, The Farmers National Bank of Canfield (“Bank”). The consolidated financial statements also include the accounts of the Bank’s subsidiaries; Farmers National Insurance, LLC (“Insurance”) and Farmers of Canfield Investment Co. (“Investments”). The Company provides trust and retirement consulting services through its subsidiary, Farmers Trust Company (“Trust”), and insurance services through the Bank’s subsidiary, Insurance. Farmers National Captive, Inc. (“Captive”) is a wholly-owned insurance subsidiary of the Company that provides property and casualty insurance coverage to the Company and its subsidiaries. The Captive pools resources with thirteen other similar insurance company subsidiaries of financial institutions to spread a limited amount of risk among themselves and to provide insurance where not currently available or economically feasible in today’s insurance market place. The consolidated financial statements include the accounts of the Company, the Bank and its subsidiaries, along with the Trust and Captive. All significant intercompany balances and transactions have been eliminated in the consolidation.
Corporate Reorganization	Corporate Reorganization: On July 1, 2019, Trust acquired all shares of National Associates, Inc. (“NAI”) from the Company through a corporate reorganization. The Company was the sole shareholder of Trust and NAI before the reorganization. The entities were combined into one reporting unit and one operating segment and began reporting as one unit, for both internal and external reports, during the third quarter of 2019. The combination is part of the Company’s plan to increase efficiencies within the different business lines.
Basis of Presentation	Basis of Presentation: The unaudited condensed consolidated financial statements have been prepared in conformity with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“U.S. GAAP”) for complete financial statements. The financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s 2018 Annual Report to Shareholders included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The interim consolidated financial statements include all adjustments (consisting of only normal recurring items) that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods presented. The results of operations for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year. Certain items included in the prior period financial statements were reclassified to conform to the current period presentation. There was no effect on net income or total stockholders’ equity.
Estimates	Estimates: The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Segments	Segments: The Company provides a broad range of financial services to individuals and companies in northeastern Ohio and western Pennsylvania. Operations are managed and financial performance is primarily aggregated and reported in two lines of business, the Bank segment and the Trust segment. During the current quarter the Company merged the Retirement Consulting segment into the Trust segment. In prior periods segment reporting was reported in three segments.
Equity	Equity: The Company, with the approval of shareholders at the April 2018 annual meeting, increased the authorized shares available for issuance from 35,000,000 to 50,000,000 shares. Outstanding shares at September 30, 2019 were 27,668,632.
Comprehensive Income	Comprehensive Income: Comprehensive income consists of net income and other comprehensive income. Other comprehensive income consists of unrealized gains and losses on securities available for sale which are recognized as components of stockholders’ equity, net of tax effect.
New Accounting Standards	New Accounting Standards: In June 2018, the FASB issued ASU 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The amendments in this ASU are effective for the reporting periods after December 15, 2018. The Company adopted ASU No. 2017-12 effective January 1, 2019. There was no significant impact to the consolidated financial statements as a result of the adoption of ASU 2017-12. In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. This ASU better aligns an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. The amendments in this ASU are effective for the reporting periods after December 15, 2018. The Company adopted ASU No. 2017-12 effective January 1, 2019. There was no significant impact to the consolidated financial statements as a result of the adoption of ASU 2017-12. During April of 2017, the FASB issued ASU 2017-08, Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. Under current U.S. GAAP, a premium is typically amortized to the maturity date when a callable debt security is purchased at a premium, even if the holder is certain the call will be exercised. As a result, upon the exercise of a call on a callable debt security held at a premium, the unamortized premium is recorded as a loss in earnings. The new standard shortens the amortization period for the premium to the earliest call date to more closely align interest income recorded on bonds held at a premium or a discount with the economics of the underlying instrument. The standard takes effect for public business entities for fiscal years and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in an interim period. The Company early adopted this ASU effective January 1, 2018 and there was no material impact on its Consolidated Financial Statements. In January 2017, the FASB issued ASU 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. This ASU eliminates Step 2 from the goodwill impairment test. Instead, under the new guidance, an entity is to perform its annual goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An impairment charge would be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value. The new guidance is effective for annual reporting periods, and interim reporting periods within those annual periods, beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company does not plan on early adoption of this ASU. The adoption of this guidance is not expected to have an impact on the Company’s Consolidated Financial Statements. In June 2016, the FASB issued ASU 2016-13: Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (modified by ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments Credit Losses). The ASU requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. Many of the loss estimation techniques applied today will still be permitted, although the inputs to those techniques will change to reflect the full amount of expected credit losses. Organizations will continue to use judgment to determine which loss estimation method is appropriate for their circumstances. Additionally, the ASU amends the accounting for credit losses on available for sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 is effective for public companies for annual periods beginning after December 15, 2019, including interim periods within that fiscal year. Entities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The Company has established an internal committee, accumulated historical credit information and validated the installation of the data. The Company continues the process of implementation and is now in the process of running the new system parallel to the current system to ensure all issues have been addressed. Based on the testing of the system management has estimated the impact of the new standard will increase the current reserve for loan losses in the range of 10% to 20% upon adoption of the standard. This preliminary estimate is contingent upon continued testing and refinement of models, methodologies and judgements. Adoption of ASU 2016-13 will happen on January 1, 2020. In February 2016, FASB issued ASU 2016-02 (Topic 842): Leases. The main objective of ASU 2016-02 is to provide users with useful, transparent, and complete information about leasing transactions. ASU 2016-02 requires the rights and obligations associated with leasing arrangements be reflected on the balance sheet in order to increase transparency and comparability among organizations. Under the updated guidance, lessees will be required to recognize a right-to-use asset and a liability to make a lease payment and disclose key information about leasing arrangements. ASU 2016-02 is effective for public companies for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Company adopted this ASU on January 1, 2019. As disclosed in the lease footnote, certain leases that the Company has in place required the capitalization of $3.6 million on the balance sheet as an asset and a related liability in the same amount with no income statement effect at January 1, 2019. The balance of the right-to-use asset and liability is $3.3 million at September 30, 2019. In January 2016, FASB issued ASU 2016-01: Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The main objective of ASU 2016-01 is to enhance the reporting model for financial instruments to provide users of financial statements with more decision-useful information. ASU 2016-01 addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. Some of the amendments in ASU 2016-01 include the following: 1) Require equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; 2) Simplify the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; 3) Require public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; and 4) Require an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value; among others. The amendments of ASU 2016-01 are effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted this ASU 2016-01 on January 1, 2018 which resulted in a $169 thousand increase to beginning retained earnings and a $169 thousand decrease to accumulated other comprehensive income on the December 31, 2018 Consolidated Financial Statements. In May 2014, FASB issued ASU 2014-09: Revenue from Contracts with Customers (Topic 606). The ASU creates a new topic, Topic 606, to provide guidance on revenue recognition for entities that enter into contracts with customers to transfer goods or services or enter into contracts for the transfer of nonfinancial assets. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Additional disclosures are required to provide quantitative and qualitative information regarding the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The new guidance is effective for the Company’s year ending December 31, 2018 and was adopted as of January 1, 2018. Interest income is outside of the scope of the new standard and was not impacted by the adoption of the standard. An evaluation of the Company’s noninterest income streams resulted in no change in revenue recognition at adoption, nor did it change revenue recognition prospectively in a significant way. Refer to the Revenue from Contracts with Customers footnote for further discussion on the Company’s accounting for revenue sources within the scope of ASC 606. The Company adopted ASC 606 using the modified retrospective method applied to all contracts not completed as of January 1, 2018. The adoption of ASC 606 did not result in a change to the accounting for any of the in-scope revenue streams; as such, no cumulative effect adjustment was recorded.

Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2019

Principles of Consolidation:

Farmers National Banc Corp. (“Company”) is a Financial Holding Company registered under the Bank Holding Company Act of 1956, as amended. The Company provides full banking services through its nationally chartered subsidiary, The Farmers National Bank of Canfield (“Bank”). The consolidated financial statements also include the accounts of the Bank’s subsidiaries; Farmers National Insurance, LLC (“Insurance”) and Farmers of Canfield Investment Co. (“Investments”). The Company provides trust and retirement consulting services through its subsidiary, Farmers Trust Company (“Trust”), and insurance services through the Bank’s subsidiary, Insurance. Farmers National Captive, Inc. (“Captive”) is a wholly-owned insurance subsidiary of the Company that provides property and casualty insurance coverage to the Company and its subsidiaries. The Captive pools resources with thirteen other similar insurance company subsidiaries of financial institutions to spread a limited amount of risk among themselves and to provide insurance where not currently available or economically feasible in today’s insurance market place. The consolidated financial statements include the accounts of the Company, the Bank and its subsidiaries, along with the Trust and Captive. All significant intercompany balances and transactions have been eliminated in the consolidation.

Corporate Reorganization

Corporate Reorganization:

On July 1, 2019, Trust acquired all shares of National Associates, Inc. (“NAI”) from the Company through a corporate reorganization. The Company was the sole shareholder of Trust and NAI before the reorganization. The entities were combined into one reporting unit and one operating segment and began reporting as one unit, for both internal and external reports, during the third quarter of 2019. The combination is part of the Company’s plan to increase efficiencies within the different business lines.

Basis of Presentation

Basis of Presentation:

The unaudited condensed consolidated financial statements have been prepared in conformity with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. generally accepted accounting principles (“U.S. GAAP”) for complete financial statements. The financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s 2018 Annual Report to Shareholders included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The interim consolidated financial statements include all adjustments (consisting of only normal recurring items) that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods presented. The results of operations for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year. Certain items included in the prior period financial statements were reclassified to conform to the current period presentation. There was no effect on net income or total stockholders’ equity.

Estimates

Estimates:

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Segments

Segments:

The Company provides a broad range of financial services to individuals and companies in northeastern Ohio and western Pennsylvania. Operations are managed and financial performance is primarily aggregated and reported in two lines of business, the Bank segment and the Trust segment. During the current quarter the Company merged the Retirement Consulting segment into the Trust segment. In prior periods segment reporting was reported in three segments.

Equity

Equity:

The Company, with the approval of shareholders at the April 2018 annual meeting, increased the authorized shares available for issuance from 35,000,000 to 50,000,000 shares. Outstanding shares at September 30, 2019 were 27,668,632.

Comprehensive Income

Comprehensive Income:

Comprehensive income consists of net income and other comprehensive income. Other comprehensive income consists of unrealized gains and losses on securities available for sale which are recognized as components of stockholders’ equity, net of tax effect.

New Accounting Standards

New Accounting Standards:

In June 2018, the FASB issued ASU 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting. This ASU expands the scope of Topic 718 to include share-based payment transactions for acquiring goods and services from nonemployees. The amendments in this ASU are effective for the reporting periods after December 15, 2018. The Company adopted ASU No. 2017-12 effective January 1, 2019. There was no significant impact to the consolidated financial statements as a result of the adoption of ASU 2017-12.

In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. This ASU better aligns an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. The amendments in this ASU are effective for the reporting periods after December 15, 2018. The Company adopted ASU No. 2017-12 effective January 1, 2019. There was no significant impact to the consolidated financial statements as a result of the adoption of ASU 2017-12.

During April of 2017, the FASB issued ASU 2017-08, Receivables-Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities. Under current U.S. GAAP, a premium is typically amortized to the maturity date when a callable debt security is purchased at a premium, even if the holder is certain the call will be exercised. As a result, upon the exercise of a call on a callable debt security held at a premium, the unamortized premium is recorded as a loss in earnings. The new standard shortens the amortization period for the premium to the earliest call date to more closely align interest income recorded on bonds held at a premium or a discount with the economics of the underlying instrument. The standard takes effect for public business entities for fiscal years and interim periods within those fiscal years, beginning after December 15, 2018. Early adoption is permitted, including adoption in an interim period. The Company early adopted this ASU effective January 1, 2018 and there was no material impact on its Consolidated Financial Statements.

In January 2017, the FASB issued ASU 2017-04, Intangibles-Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. This ASU eliminates Step 2 from the goodwill impairment test. Instead, under the new guidance, an entity is to perform its annual goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An impairment charge would be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value. The new guidance is effective for annual reporting periods, and interim reporting periods within those annual periods, beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company does not plan on early adoption of this ASU. The adoption of this guidance is not expected to have an impact on the Company’s Consolidated Financial Statements.

In June 2016, the FASB issued ASU 2016-13: Financial Instruments-Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (modified by ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments Credit Losses). The ASU requires an organization to measure all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to better inform their credit loss estimates. Many of the loss estimation techniques applied today will still be permitted, although the inputs to those techniques will change to reflect the full amount of expected credit losses. Organizations will continue to use judgment to determine which loss estimation method is appropriate for their circumstances. Additionally, the ASU amends the accounting for credit losses on available for sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 is effective for public companies for annual periods beginning after December 15, 2019, including interim periods within that fiscal year. Entities will apply the standard’s provisions as a cumulative-effect adjustment to retained earnings as of the beginning of the first reporting period in which the guidance is adopted. The Company has established an internal committee, accumulated historical credit information and validated the installation of the data. The Company continues the process of implementation and is now in the process of running the new system parallel to the current system to ensure all issues have been addressed. Based on the testing of the system management has estimated the impact of the new standard will increase the current reserve for loan losses in the range of 10% to 20% upon adoption of the standard. This preliminary estimate is contingent upon continued testing and refinement of models, methodologies and judgements. Adoption of ASU 2016-13 will happen on January 1, 2020.

In February 2016, FASB issued ASU 2016-02 (Topic 842): Leases. The main objective of ASU 2016-02 is to provide users with useful, transparent, and complete information about leasing transactions. ASU 2016-02 requires the rights and obligations associated with leasing arrangements be reflected on the balance sheet in order to increase transparency and comparability among organizations. Under the updated guidance, lessees will be required to recognize a right-to-use asset and a liability to make a lease payment and disclose key information about leasing arrangements. ASU 2016-02 is effective for public companies for interim and annual reporting periods beginning after December 15, 2018, with early adoption permitted. The Company adopted this ASU on January 1, 2019. As disclosed in the lease footnote, certain leases that the Company has in place required the capitalization of $3.6 million on the balance sheet as an asset and a related liability in the same amount with no income statement effect at January 1, 2019. The balance of the right-to-use asset and liability is $3.3 million at September 30, 2019.

In January 2016, FASB issued ASU 2016-01: Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The main objective of ASU 2016-01 is to enhance the reporting model for financial instruments to provide users of financial statements with more decision-useful information. ASU 2016-01 addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. Some of the amendments in ASU 2016-01 include the following: 1) Require equity investments (except those accounted for under the equity method of accounting or those that result in consolidation of the investee) to be measured at fair value with changes in fair value recognized in net income; 2) Simplify the impairment assessment of equity investments without readily determinable fair values by requiring a qualitative assessment to identify impairment; 3) Require public business entities to use the exit price notion when measuring the fair value of financial instruments for disclosure purposes; and 4) Require an entity to present separately in other comprehensive income the portion of the total change in the fair value of a liability resulting from a change in the instrument-specific credit risk when the entity has elected to measure the liability at fair value; among others. The amendments of ASU 2016-01 are effective for fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. The Company adopted this ASU 2016-01 on January 1, 2018 which resulted in a $169 thousand increase to beginning retained earnings and a $169 thousand decrease to accumulated other comprehensive income on the December 31, 2018 Consolidated Financial Statements.

In May 2014, FASB issued ASU 2014-09: Revenue from Contracts with Customers (Topic 606). The ASU creates a new topic, Topic 606, to provide guidance on revenue recognition for entities that enter into contracts with customers to transfer goods or services or enter into contracts for the transfer of nonfinancial assets. The core principle of the guidance is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. Additional disclosures are required to provide quantitative and qualitative information regarding the nature, amount, timing, and uncertainty of revenue and cash flows arising from contracts with customers. The new guidance is effective for the Company’s year ending December 31, 2018 and was adopted as of January 1, 2018. Interest income is outside of the scope of the new standard and was not impacted by the adoption of the standard. An evaluation of the Company’s noninterest income streams resulted in no change in revenue recognition at adoption, nor did it change revenue recognition prospectively in a significant way. Refer to the Revenue from Contracts with Customers footnote for further discussion on the Company’s accounting for revenue sources within the scope of ASC 606.

The Company adopted ASC 606 using the modified retrospective method applied to all contracts not completed as of January 1, 2018. The adoption of ASC 606 did not result in a change to the accounting for any of the in-scope revenue streams; as such, no cumulative effect adjustment was recorded.