XML 45 R45.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 4 - Loans and Allowance for Loan Losses (Details) - Age Analysis of Past Due Loans (USD $) | Mar. 31, 2015 | Dec. 31, 2014 | Mar. 31, 2014
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Commercial: |  |  |
Loans | $ 2,120,760,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome | $ 2,089,277,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome |
Commercial and Industrial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Commercial and Industrial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 285,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 29,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Commercial and Industrial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Commercial and Industrial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 32,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 711,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 76,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Commercial and Industrial [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans- Current | 434,211,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 384,570,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans | 434,211,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 384,570,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Commercial and Industrial [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 996,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 137,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans- Current | 152,468,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 165,900,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans | 153,464,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 166,037,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Commercial and Industrial [Member] |  |  |
Commercial: |  |  |
Loans | 587,675,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 550,607,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 26,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 38,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans- Current | 35,948,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 29,826,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans | 35,948,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 29,826,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 26,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 38,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans- Current | 20,076,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 22,110,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans | 20,102,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 22,148,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Commercial: |  |  |
Loans | 56,050,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 51,974,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,371,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 51,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 425,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 106,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 120,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,041,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 1,625,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Owner Occupied Loan [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 106,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 120,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans- Current | 302,273,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 291,638,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans | 302,379,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 291,758,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 2,412,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 2,101,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans- Current | 127,204,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 136,529,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans | 129,616,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 138,630,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Real Estate Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans | 431,995,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 430,388,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 68,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 598,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 113,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 116,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 296,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 395,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 113,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 116,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans- Current | 423,268,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 410,861,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans | 423,381,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 410,977,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 296,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 1,061,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans- Current | 142,475,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 147,536,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans | 142,771,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 148,597,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Real Estate Non Owner Occupied Loan [Member] |  |  |
Commercial: |  |  |
Loans | 566,152,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 559,574,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 37,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 69,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 93,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 105,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans- Current | 34,922,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 36,058,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans | 34,922,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 36,058,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 162,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 142,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans- Current | 82,393,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 86,560,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans | 82,555,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 86,702,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Commercial: |  |  |
Loans | 117,477,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 122,760,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Commercial Portfolio Segment [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,682,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 185,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Commercial Portfolio Segment [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 69,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 1,093,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 219,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 236,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Commercial Portfolio Segment [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 2,141,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 2,201,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 219,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 236,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans- Current | 1,230,622,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 1,152,953,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans | 1,230,841,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 1,153,189,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 3,892,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 3,479,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans- Current | 524,616,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 558,635,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans | 528,508,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 562,114,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_CommercialPortfolioSegmentMember |
Home Equity and Other [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 133,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 38,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Home Equity and Other [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 245,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 445,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Home Equity and Other [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 300,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 3,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Home Equity and Other [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 90,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 419,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Home Equity and Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Home Equity and Other [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 362,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 155,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Home Equity and Other [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 433,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 41,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans- Current | 53,274,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 50,018,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans | 53,707,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 50,059,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Home Equity and Other [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 697,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 1,019,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans- Current | 98,582,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 108,200,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans | 99,279,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 109,219,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 26,000 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Home Equity and Other [Member] |  |  |
Commercial: |  |  |
Loans | 152,986,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 159,278,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
1-4 Family Mortgages [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
1-4 Family Mortgages [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,204,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 1,087,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
1-4 Family Mortgages [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 84,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 0 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
1-4 Family Mortgages [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 54,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 408,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
1-4 Family Mortgages [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 321,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 366,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
1-4 Family Mortgages [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,021,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 750,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
1-4 Family Mortgages [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 405,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 366,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans- Current | 43,760,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 42,502,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans | 44,165,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 42,868,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
1-4 Family Mortgages [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 2,279,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 2,245,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans- Current | 161,981,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 169,583,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans | 164,260,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 171,828,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
1-4 Family Mortgages [Member] |  |  |
Commercial: |  |  |
Loans | 208,425,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 214,696,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Retail Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 133,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 38,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Retail Loan [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,449,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 1,532,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Retail Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 384,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 3,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Retail Loan [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 144,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 827,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Retail Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 321,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 366,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Retail Loan [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,383,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 905,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Retail Loan [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 838,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 407,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans- Current | 97,034,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 92,520,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans | 97,872,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 92,927,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Retail Loan [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 2,976,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 3,264,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans- Current | 260,563,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 277,783,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans | 263,539,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 281,047,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 26,000 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Retail Loan [Member] |  |  |
Commercial: |  |  |
Loans | 361,411,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember | 373,974,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RetailLoanMember |
Financing Receivables, 30 to 59 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 133,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 38,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Financing Receivables, 30 to 59 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 3,131,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember | 1,717,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables30To59DaysPastDueMember |
Financing Receivables, 60 to 89 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 384,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 3,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Financing Receivables, 60 to 89 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 213,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember | 1,920,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivables60To89DaysPastDueMember |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 540,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 602,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 3,524,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember | 3,106,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablesPeriodPastDueAxis = us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember |
Originated Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 1,057,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 643,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Loans- Current | 1,327,656,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 1,245,473,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Loans | 1,328,713,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 1,246,116,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 1,066,796,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember
Loans- Recorded Balance >89days and accruing | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Acquired Loan [Member] |  |  |
Commercial: |  |  |
Loans- 30 to 59 days past due | 6,868,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember | 6,743,000 us-gaap_FinancingReceivableRecordedInvestmentPastDue / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Loans- Current | 785,179,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember | 836,418,000 us-gaap_FinancingReceivableRecordedInvestmentCurrent / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Loans | 792,047,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember | 843,161,000 us-gaap_LoansAndLeasesReceivableNetOfDeferredIncome / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Loans- Recorded Balance >89days and accruing | $ 0 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember | $ 26,000 us-gaap_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |

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- Details
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Namespace Prefix: | mbwm_
Data Type: | xbrli:stringItemType
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Period Type: | duration

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- Definition Recorded investment in financing receivables that are 90 days or more past due and still accruing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing receivables that are current. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953401-111524 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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