XML 67 R53.htm IDEA: XBRL DOCUMENT
v3.22.1

Loans (Details Textual) | 3 Months Ended
--- | ---
Mar. 31, 2022 USD ($)
Receivables [Abstract] |
Deferred loan payments | $ 0

X
- Definition Deferred loan payments. + References No definition available. + Details
Name: | fmnb_DeferredLoanPayments
Namespace Prefix: | fmnb_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ReceivablesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration