XML 25 R52.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 4 - Loans and Allowance for Loan Losses (Details) - Activity for Troubled Debt Restructurings (USD $) | 3 Months Ended
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Mar. 31, 2015 | Mar. 31, 2014
Commercial and Industrial [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | $ 7,026,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | $ 1,656,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Ending Balance | 6,556,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 1,404,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Payments | (1,155,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | (266,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Net Additions/Deletions | 685,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 14,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Commercial and Industrial [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 1,439,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Ending Balance | 1,519,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Payments | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Net Additions/Deletions | 80,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 2,680,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 4,501,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Ending Balance | 2,654,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 4,250,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Payments | (26,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | (3,149,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 2,898,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Ending Balance | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Payments | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Real Estate Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 17,160,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 1,816,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Ending Balance | 16,966,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 1,756,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | (11,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Payments | (194,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | (49,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 1,569,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Ending Balance | 1,492,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Payments | (179,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Net Additions/Deletions | 102,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 17,439,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 22,311,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Ending Balance | 16,063,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 21,629,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Payments | (1,376,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | (1,001,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 319,000 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 64,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Ending Balance | 62,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Payments | (2,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 505,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 2,620,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Ending Balance | 498,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 732,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | (420,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Payments | (7,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | (1,468,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Real Estate Multi Family and Residential Rental Loan [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 381,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Ending Balance | 333,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Payments | (48,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Home Equity and Other [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Ending Balance | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Payments | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Home Equity and Other [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 26,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Ending Balance | 0 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Payments | (26,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
1-4 Family Mortgages [Member] | Originated Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 1,967,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 2,191,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Ending Balance | 302,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 2,122,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Charge-Offs | (125,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Payments | (1,540,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | (69,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Net Additions/Deletions | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
1-4 Family Mortgages [Member] | Acquired Loan [Member] |  |
Commercial Loan Portfolio: |  |
Beginning Balance | 178,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Ending Balance | 177,000 us-gaap_FinancingReceivableModificationsRecordedInvestment / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Charge-Offs | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsChargeOffs / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Payments | (1,000)mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsPayments / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Transfers to ORE | 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsTransferToOtherRealEstate / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Net Additions/Deletions | $ 0 mbwm_FinancingReceivableModifiedAsTroubledDebtRestructuringsAdditions / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |

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- Definition A financing receivable which had its terms modified during the period and is now considered a troubled restructuring. + References No definition available. + Details
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- Definition Reflects the amount of the charge-off related to a troubled debt restructuring. + References No definition available. + Details
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- Definition The cash outflow associated with a financing receivable classified as a troubled debt restructuring. + References No definition available. + Details
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- Definition The transfer of a financing receivable classified as a troubled debt restructuring to other real estate. + References No definition available. + Details
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- Definition The amount of the outstanding recorded investment related to 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 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554 + Details
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