XML 66 R54.htm IDEA: XBRL DOCUMENT
v3.22.4

Basis of Accounting and Consolidation - Schedule of Impact of ASU 2016-13 Adoption of PCD Assets Previously Classified as PCI (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019
--- | --- | --- | --- | --- | ---
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans | $ 59,093,000 | $ 54,655,000 | $ 41,910,000 |  | $ 26,911,000
Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  | 26,911,000 |  |  |
ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | $ 28,583,000 |
ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 1,672,000 |
Construction and Land Development | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  | 1,146,000 |  |  |
Construction and Land Development | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 1,033,000 |
Construction and Land Development | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | (113,000) |
1-4 Family Residential Properties | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  | 1,386,000 |  |  |
1-4 Family Residential Properties | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 2,142,000 |
1-4 Family Residential Properties | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 756,000 |
Commercial Real Estate | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  | 11,198,000 |  |  |
Commercial Real Estate | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 11,739,000 |
Commercial Real Estate | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 541,000 |
Commercial & Industrial | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  | $ 9,273,000 |  |  |
Commercial & Industrial | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 9,428,000 |
Commercial & Industrial | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 155,000 |
Financial Asset Acquired with Credit Deterioration | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  | 365,000 |  |
Financial Asset Acquired with Credit Deterioration | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 1,198,000 |
Financial Asset Acquired with Credit Deterioration | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 833,000 |
Financial Asset Acquired with Credit Deterioration | Construction and Land Development | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 291,000 |
Financial Asset Acquired with Credit Deterioration | Construction and Land Development | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 291,000 |
Financial Asset Acquired with Credit Deterioration | 1-4 Family Residential Properties | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  | 6,000 |  |
Financial Asset Acquired with Credit Deterioration | 1-4 Family Residential Properties | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 48,000 |
Financial Asset Acquired with Credit Deterioration | 1-4 Family Residential Properties | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 42,000 |
Financial Asset Acquired with Credit Deterioration | Commercial Real Estate | Pre-ASU |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  | $ 359,000 |  |
Financial Asset Acquired with Credit Deterioration | Commercial Real Estate | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 818,000 |
Financial Asset Acquired with Credit Deterioration | Commercial Real Estate | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 459,000 |
Financial Asset Acquired with Credit Deterioration | Commercial & Industrial | ASU 2016-13 |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | 41,000 |
Financial Asset Acquired with Credit Deterioration | Commercial & Industrial | ASU 2016-13 | Revision of Prior Period, Adjustment |  |  |  |  |
New Accounting Pronouncements Or Change In Accounting Principle [Line Items] |  |  |  |  |
Allowance for credit losses on loans |  |  |  | $ 41,000 |

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (3) Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (c) Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (1) + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_RestatementAxis=srt_ScenarioPreviouslyReportedMember
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_RestatementAxis=srt_RestatementAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=fmbh_ConstructionAndLandDevelopmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=fmbh_ResidentialPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommercialRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CreditLossStatusAxis=us-gaap_FinancialAssetAcquiredWithCreditDeteriorationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |