XML 28 R78.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings (USD $) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013
Commercial: |  |
Loans modified, number of contracts |  | 10 us-gaap_FinancingReceivableModificationsNumberOfContracts2
Loans modified, pre-modification recorded principal balance |  | $ 7,231,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Loans modified, post-modification recorded principal balance |  | 7,231,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Commercial and Industrial [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember | 3 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember
Loans modified, pre-modification recorded principal balance | 5,994,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember | 741,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember
Loans modified, post-modification recorded principal balance | 6,094,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember | 741,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember
Commercial and Industrial [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 7 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember |
Loans modified, pre-modification recorded principal balance | 1,604,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember |
Loans modified, post-modification recorded principal balance | 1,604,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialAndIndustrialMember |
Commercial Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 3,610,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 3,610,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Commercial Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialVacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Commercial Real Estate Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember
Loans modified, pre-modification recorded principal balance | 16,787,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember | 715,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember
Loans modified, post-modification recorded principal balance | 16,787,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember | 715,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember
Commercial Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember |
Loans modified, pre-modification recorded principal balance | 1,619,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember |
Loans modified, post-modification recorded principal balance | 1,619,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateOwnerOccupiedLoanMember |
Commercial Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember
Loans modified, pre-modification recorded principal balance | 146,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember | 45,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember
Loans modified, post-modification recorded principal balance | 146,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember | 45,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember
Commercial Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember |
Loans modified, pre-modification recorded principal balance | 65,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember |
Loans modified, post-modification recorded principal balance | 65,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateNonOwnerOccupiedLoanMember |
Commercial Real Estate Multi Family and Residential Rental Loan [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember | 241,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember | 241,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember
Commercial Real Estate Multi Family and Residential Rental Loan [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 4 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans modified, pre-modification recorded principal balance | 394,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember |
Loans modified, post-modification recorded principal balance | 394,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_CommercialRealEstateMultiFamilyAndResidentialRentalLoanMember |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 5 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember | 9 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember
Loans modified, pre-modification recorded principal balance | 22,927,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember | 5,352,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember
Loans modified, post-modification recorded principal balance | 23,027,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember | 5,352,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 14 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans modified, pre-modification recorded principal balance | 3,682,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember |
Loans modified, post-modification recorded principal balance | 3,682,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = us-gaap_CommercialPortfolioSegmentMember |
Retail Home Equity and Other [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Retail Home Equity and Other [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Loans modified, pre-modification recorded principal balance | 26,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Loans modified, post-modification recorded principal balance | 26,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember |
Retail Home Equity and Other [Member] |  |
Commercial: |  |
Loans modified, number of contracts |  | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember
Loans modified, pre-modification recorded principal balance |  | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember
Loans modified, post-modification recorded principal balance |  | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailHomeEquityAndOtherMember
Retail 1-4 Family Mortgages [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Retail 1-4 Family Mortgages [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Loans modified, pre-modification recorded principal balance | 179,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Loans modified, post-modification recorded principal balance | 179,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember |
Retail 1-4 Family Mortgages [Member] |  |
Commercial: |  |
Loans modified, number of contracts |  | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember
Loans modified, pre-modification recorded principal balance |  | 1,879,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember
Loans modified, post-modification recorded principal balance |  | 1,879,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_Retail1To4FamilyMortgagesMember
Retail Loan [Member] | Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 0 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Loans modified, pre-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Loans modified, post-modification recorded principal balance | 0 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Retail Loan [Member] | Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 2 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Loans modified, pre-modification recorded principal balance | 205,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Loans modified, post-modification recorded principal balance | 205,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember |
Retail Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts |  | 1 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember
Loans modified, pre-modification recorded principal balance |  | 1,879,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember
Loans modified, post-modification recorded principal balance |  | 1,879,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancingReceivableTroubledDebtRestructuringAxis = mbwm_RetailLoanMember
Originated Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 5 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Loans modified, pre-modification recorded principal balance | 22,927,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Loans modified, post-modification recorded principal balance | 23,027,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember |
Acquired Loan [Member] |  |
Commercial: |  |
Loans modified, number of contracts | 16 us-gaap_FinancingReceivableModificationsNumberOfContracts2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Loans modified, pre-modification recorded principal balance | 3,887,000 us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Loans modified, post-modification recorded principal balance | $ 3,887,000 us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |

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- Details
Name: | mbwm_CommercialAbstract0000000000000
Namespace Prefix: | mbwm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524 + Details
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