XML 12 R44.htm IDEA: XBRL DOCUMENT
v3.19.3

Summary of Significant Accounting Policies (Details Textual) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2019 USD ($) Reporting Segment shares | Sep. 30, 2019 USD ($) Segment shares | Dec. 31, 2018 USD ($) Segment shares | Jan. 01, 2019 USD ($) | Apr. 30, 2018 shares | Jan. 01, 2018 USD ($) | Dec. 31, 2017 USD ($) shares
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Operating lease, right-of-use asset | $ 3,300 | $ 3,300 |  |  |  |  |
Operating lease, liability | $ 3,301 | $ 3,301 |  |  |  |  |
Operating segments of business | Segment |  | 2 | 3 |  |  |  |
Common stock, authorized shares available for issuance | shares | 50,000,000 | 50,000,000 | 50,000,000 |  | 50,000,000 |  | 35,000,000
Common stock, shares outstanding | shares | 27,668,632 | 27,668,632 |  |  |  |  |
Retained Earnings |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Cumulative effect adjustment upon adoption of new accounting principle |  |  | $ 0 |  |  |  | $ 169
Accumulated Other Comprehensive Income |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Cumulative effect adjustment upon adoption of new accounting principle |  |  | $ 0 |  |  |  | $ (169)
ASU 2016-13 | Minimum |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Estimated increase in percentage of current reserve for loan losses |  | 10.00% |  |  |  |  |
ASU 2016-13 | Maximum |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Estimated increase in percentage of current reserve for loan losses |  | 20.00% |  |  |  |  |
ASU 2016-02 |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Capitalization of leases as an asset |  |  |  | $ 3,600 |  |  |
Operating lease, right-of-use asset | $ 3,300 | $ 3,300 |  |  |  |  |
Operating lease, liability | $ 3,300 | $ 3,300 |  |  |  |  |
ASU 2016-01 | Retained Earnings |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Cumulative effect adjustment upon adoption of new accounting principle |  |  |  |  |  | $ 169 |
ASU 2016-01 | Accumulated Other Comprehensive Income |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Cumulative effect adjustment upon adoption of new accounting principle |  |  |  |  |  | $ 169 |
NAI |  |  |  |  |  |  |
Summary of Significant Accounting Policies (Additional Textual) [Abstract] |  |  |  |  |  |  |
Number of reporting units | Reporting | 1 |  |  |  |  |  |
Number of reportable segments | Segment | 1 |  |  |  |  |  |

X
- Definition Estimated increase in percentage of current reserve for loan losses. + References No definition available. + Details
Name: | fmnb_EstimatedIncreaseInPercentageOfCurrentReserveForLoanLosses
Namespace Prefix: | fmnb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Summary of significant accounting policies additional textual. + References No definition available. + Details
Name: | fmnb_SummaryOfSignificantAccountingPoliciesAdditionalTextualAbstract
Namespace Prefix: | fmnb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 + Details
Name: | us-gaap_CapitalLeasesBalanceSheetAssetsByMajorClassNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. + References No definition available. + Details
Name: | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
Name: | us-gaap_NumberOfOperatingSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
Name: | us-gaap_NumberOfReportableSegments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment. + References No definition available. + Details
Name: | us-gaap_NumberOfReportingUnits
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977 + Details
Name: | us-gaap_OperatingLeaseRightOfUseAsset
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_AccumulatedOtherComprehensiveIncomeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201613Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201601Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=fmnb_NationalAssociatesIncorporatedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |