XML 78 R68.htm IDEA: XBRL DOCUMENT
v3.23.2

Fair Value of Assets and Liabilities - Significant Unobservable Inputs Used in Valuation of Level 3 Fair Value Measurements (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2023 | Dec. 31, 2022
Collateral Dependent Loans | Level 3 | Minimum | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 0.00% | 0.00%
Collateral Dependent Loans | Level 3 | Maximum | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 40.00% | 40.00%
Collateral Dependent Loans | Level 3 | Weighted Average | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 20.00% | 20.00%
Foreclosed Assets Held-for-sale | Level 3 | Minimum | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 0.00% |
Foreclosed Assets Held-for-sale | Level 3 | Maximum | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 40.00% |
Foreclosed Assets Held-for-sale | Level 3 | Weighted Average | Third Party Valuations |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Collateral dependent loans | 35.00% |
Fair Value, Nonrecurring | Collateral Dependent Loans |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 1,106 | $ 2,548
Fair Value, Nonrecurring | Collateral Dependent Loans | Level 3 |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value | 1,106 | $ 2,548
Fair Value, Nonrecurring | Foreclosed Assets Held-for-sale |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value | $ 14 |

X
- Definition Discount to reflect realizable value used when pricing the investments. + References No definition available. + Details
Name: | fmbh_DiscountToReflectRealizableValue
Namespace Prefix: | fmbh_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_AssetsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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. + Details
Name: | us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=fmbh_CollateralDependentLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
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: | us-gaap_ValuationTechniqueAxis=us-gaap_MarketApproachValuationTechniqueMember
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: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=fmbh_ForeclosedAssetsHeldForSaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |