XML 74 R51.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due (USD $) | 3 Months Ended
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Mar. 31, 2015 | Mar. 31, 2014
Commercial and Industrial [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Recorded principal balance | $ 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember | $ 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember
Commercial and Industrial [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_CommercialAndIndustrialMember |
Vacant Land and Land Development and Residential Construction Loan [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember
Vacant Land and Land Development and Residential Construction Loan [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_VacantLandAndLandDevelopmentAndResidentialConstructionLoanMember |
Real Estate Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember
Real Estate Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 1 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Recorded principal balance | 1,339,000 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateOwnerOccupiedLoanMember |
Real Estate Non Owner Occupied Loan [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember
Real Estate Non Owner Occupied Loan [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateNonOwnerOccupiedLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Real Estate Multi Family and Residential Rental Loan [Member] | Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 1 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Recorded principal balance | 1,339,000 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = us-gaap_CommercialPortfolioSegmentMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Real Estate Multi Family and Residential Rental Loan [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember
Real Estate Multi Family and Residential Rental Loan [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_RealEstateMultiFamilyAndResidentialRentalLoanMember |
Home Equity and Other [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember
Home Equity and Other [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_HomeEquityAndOtherMember |
1-4 Family Mortgages [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember
1-4 Family Mortgages [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = mbwm_OneToFourFamilyMortgagesMember |
Retail Loan [Member] | Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember
Retail Loan [Member] | Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember |
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember / us-gaap_FinancingReceivablePortfolioSegmentAxis = mbwm_RetailLoanMember |
Originated Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember
Recorded principal balance | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember | 0 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_OriginatedLoanMember
Acquired Loan [Member] |  |
Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings within the Previous Twelve Months That Became Over 30 Days Past Due [Line Items] |  |
Number of contracts | 1 us-gaap_FinancingReceivableModificationsSubsequentDefaultNumberOfContracts1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |
Recorded principal balance | $ 1,339,000 us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1 / us-gaap_FinancialInstrumentAxis = mbwm_AcquiredLoanMember |

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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524 + Details
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- Definition Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524 + Details
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