XML 53 R44.htm IDEA: XBRL DOCUMENT
v3.23.2

Note 3 - Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans (Details) - USD ($) | Jun. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Financing Receivable, before Allowance for Credit Loss |  | $ 4,051,843,000 | $ 3,916,619,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 3,188,585,000 | 3,131,830,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,212,196,000 | 1,185,083,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 72,682,000 | 61,873,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 659,201,000 | 639,192,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss | [1] | 957,221,000 | 979,214,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss | [1] | 287,285,000 | 266,468,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 863,258,000 | 784,789,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 833,198,000 | 755,036,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 30,060,000 | 29,753,000
Loans past due 90 days or more still accruing interest |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 606,000 | 1,349,000
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 606,000 | 1,349,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 602,000 | 1,334,000
Financial Asset, 30 to 59 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 4,000 | 15,000
Financial Asset, 60 to 89 Days Past Due [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 87,000 | 6,042,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 5,953,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 5,705,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 248,000
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 87,000 | 89,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 83,000 | 88,000
Financial Asset, 60 to 89 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 4,000 | 1,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 549,000 | 365,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 365,000 | 249,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 249,000 | 249,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 116,000 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 184,000 | 116,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 184,000 | 116,000
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Past Due [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,242,000 | 7,756,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 365,000 | 6,202,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 249,000 | 5,954,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 116,000 | 248,000
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 0 | 0
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 877,000 | 1,554,000
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 869,000 | 1,538,000
Financial Asset, Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 8,000 | 16,000
Financial Asset, Not Past Due [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 4,050,601,000 | 3,908,863,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 3,188,220,000 | 3,125,628,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 1,211,947,000 | 1,179,129,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 72,682,000 | 61,873,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 659,085,000 | 638,944,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 957,221,000 | 979,214,000
Financial Asset, Not Past Due [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 287,285,000 | 266,468,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 862,381,000 | 783,235,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | 832,329,000 | 753,498,000
Financial Asset, Not Past Due [Member] | Retail Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |
Financing Receivable, before Allowance for Credit Loss |  | $ 30,052,000 | $ 29,737,000
[1] | We have made certain reclassifications of how multi-family construction loans are disaggregated by loan segment. The table above reflects an increase of $54.5 million in Real Estate – Multi-Family and Residential Rental loans and a corresponding decrease in Real Estate – Non-Owner Occupied loans as of December 31, 2022. All the tables that follow have been adjusted to reflect the reclassifications as of the applicable dates.

X
- Definition Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 80 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-80 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-16 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Subparagraph (b) -SubTopic 10 -Topic 310 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-7 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 80 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-80 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 79 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479294/326-20-55-79 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (1) -Publisher SEC Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (2) -Publisher SEC Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Name Regulation S-K (SK) -Number 229 -Section 1404 -Paragraph (a) -Publisher SEC Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-14 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 7A -SubTopic 10 -Topic 310 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-7A Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_NotesReceivableGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_CommercialAndIndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_RealEstateOwnerOccupiedLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_RealEstateNonOwnerOccupiedLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=mbwm_RetailPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_OneToFourFamilyMortgagesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=mbwm_OtherConsumerLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables60To89DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |