Short-term borrowings (Details Textual)	12 Months Ended
Dec. 31, 2022 USD ($) Bank	Sep. 30, 2023 USD ($)
Domestic Line of Credit
Short Term Debt [Line Items]
Access to line of credit at domestic bank	$ 35,000,000	$ 25,000,000.0
Number of domestic banks \| Bank	2
Unsecured revolving line of credit, outstanding balance	$ 0	$ 0
Revolving Credit Facility
Short Term Debt [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.50%	3.50%
Revolving Credit Facility \| Farmers National Banc Corp \| Unsecured Debt
Short Term Debt [Line Items]
Unsecured revolving line of credit, outstanding balance	$ 6,500,000	$ 5,000,000
Letter of Credit
Short Term Debt [Line Items]
Unsecured revolving line of credit, outstanding balance	$ 0	$ 0
Debt Instrument, Interest Rate, Stated Percentage	3.50%	3.50%
Pledged
Short Term Debt [Line Items]
Short-term Federal Home Loan Banks advances	$ 95,000,000
Interest rate on borrowings	4.38%

Number of domestic bank.

No definition available.

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- Definition

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480876/942-470-45-1

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The portion of the carrying amount of short-term borrowings outstanding as of the balance sheet date which accrues interest at a set, unchanging rate.

+ References

No definition available.

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