XML 130 R115.htm IDEA: XBRL DOCUMENT
v3.20.4

Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Millions | Dec. 21, 2020 USD ($) Office $ / shares | Dec. 31, 2021 Office | Jan. 15, 2021 shares | Dec. 31, 2020 shares | Sep. 30, 2020 USD ($) Office | Dec. 31, 2019 shares
--- | --- | --- | --- | --- | --- | ---
Subsequent Event [Line Items] |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  |  | 12,230,000 |  | 12,230,000
Forecast [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Number of offices as part of strategic plan | Office |  | 4 |  |  |  |
F&M [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Loans | $ 445.0 |  |  |  |  |
Deposits | $ 462.0 |  |  |  |  |
Number of office operates | Office | 11 |  |  |  |  |
Maximum [Member] | Subsequent Event [Member] | Board of Directors [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Common stock, shares outstanding | shares |  |  | 500,000 |  |  |
Ossian Financial Services, Inc [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Assets |  |  |  |  | $ 122.0 |
Loans |  |  |  |  | 58.0 |
Deposits |  |  |  |  | 108.0 |
Consolidated equity |  |  |  |  | $ 11.9 |
Aggregate cash consideration | $ 20.0 |  |  |  |  |
Share price | $ / shares | $ 67.71 |  |  |  |  |
Ossian Financial Services, Inc [Member] | Maximum [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Total consideration for acquisition | $ 12.0 |  |  |  |  |
Ossian Financial Services, Inc [Member] | Northeast Indiana [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Number of operate full service offices | Office |  |  |  |  | 2 |

X
- Definition Business combination recognized identifiable assets acquired and liabilities assumed consolidated equity. + References No definition available. + Details
Name: | fmao_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedConsolidatedEquity
Namespace Prefix: | fmao_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Business combination recognized identifiable assets acquired and liabilities assumed deposits. + References No definition available. + Details
Name: | fmao_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeposits
Namespace Prefix: | fmao_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Business combination recognized identifiable assets acquired and liabilities assumed loans net. + References No definition available. + Details
Name: | fmao_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLoansNet
Namespace Prefix: | fmao_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of office operates. + References No definition available. + Details
Name: | fmao_NumberOfOfficeOperates
Namespace Prefix: | fmao_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of offices as part of strategic plan. + References No definition available. + Details
Name: | fmao_NumberOfOfficesAsPartOfStrategicPlan
Namespace Prefix: | fmao_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of operate full service offices. + References No definition available. + Details
Name: | fmao_NumberOfOperateFullServiceOffices
Namespace Prefix: | fmao_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination. + References No definition available. + Details
Name: | us-gaap_BusinessAcquisitionSharePrice
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of assets acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472 + Details
Name: | us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockSharesOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585 + Details
Name: | us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
Name: | us-gaap_SubsequentEventLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_StatementScenarioAxis=srt_ScenarioForecastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=fmao_FAndMBankMember
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_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_TitleOfIndividualAxis=srt_DirectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_StatementGeographicalAxis=stpr_IN
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |