MBIN


Line plots across dimensions of each concept
Tables

Table of contents



us-gaap:CommonStockValue
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
us-gaap:SharesOutstanding
us-gaap:StatementEquityComponents

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareDiluted

us-gaap:InterestAndFeeIncomeLoansAndLeases

us-gaap:InterestExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:InterestIncomeExpenseNet
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:InterestPaidNet

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxExpenseBenefit
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:IncomeTaxesPaidNet

us-gaap:ProfitLoss

us-gaap:NetIncomeLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:PreferredStockDividendsIncomeStatementImpact

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:Assets
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:Liabilities

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:StockholdersEquity
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:Goodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:LongTermDebt

us-gaap:StockholdersEquity
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
us-gaap:StatementEquityComponents

us-gaap:CommonStockValue

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetIncomeLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:StatementEquityComponents

us-gaap:ProfitLoss

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:PaymentsOfDividends

mbin:Dividends6PercentPreferredStock
us-gaap:StatementEquityComponents

mbin:Dividends7PercentPreferredStock
us-gaap:StatementEquityComponents

mbin:Dividends8PercentPreferredStock
us-gaap:StatementEquityComponents
us-gaap:FairValueByAssetClass
mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetChangesInValuationInputsOrAssumptionsUsedInValuationModel
us-gaap:FairValueByAssetClass
mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOriginatedAndPurchasedServicing
us-gaap:FairValueByAssetClass
mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydown

mbin:GainLossOnSaleOfAvailableForSaleInvestmentsAmountRelatedToAociReclassification

mbin:IncomeTaxExpenseBenefitRelatedToReclassificationItems

mbin:ServicingFeesAmount

us-gaap:AllowanceForLoanAndLeaseLossRecoveryOfBadDebts
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:AllowanceForLoanAndLeaseLossesWriteOffs
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:AmortizationOfMortgageServicingRightsMSRs

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:CommunicationsAndInformationTechnology

us-gaap:DebtSecuritiesTradingUnrealizedGainLoss

us-gaap:Depreciation

us-gaap:DerivativeGainLossOnDerivativeNet
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeGainOnDerivative
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeLossOnDerivative

us-gaap:DividendsCommonStock
us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

us-gaap:FederalDepositInsuranceCorporationPremiumExpense

us-gaap:FeesAndCommissionsMortgageBankingAndServicing

us-gaap:GainLossOnSalesOfLoansNet

us-gaap:ImpairedFinancingReceivableAverageRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableInterestIncomeCashBasisMethod
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:IncreaseDecreaseInDeposits

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInTradingSecurities

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:InterestAndDividendIncomeOperating
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:InterestExpenseBorrowings

us-gaap:InterestExpenseDeposits

us-gaap:InterestIncomeDebtSecuritiesTradingOperating

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:InterestIncomeFederalHomeLoanBankAdvances

us-gaap:InterestIncomeOther

us-gaap:InterestIncomeSecuritiesTaxExempt

us-gaap:InterestIncomeSecuritiesTaxable

us-gaap:LaborAndRelatedExpense

us-gaap:LoanPortfolioExpense

us-gaap:NoninterestExpense
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:NoninterestIncome
us-gaap:ConsolidationItems
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:NoninterestIncomeOther

us-gaap:OccupancyNet

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent
us-gaap:StatementEquityComponents

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax

us-gaap:OtherNoninterestExpense

us-gaap:PaymentsForFederalHomeLoanBankAdvances

us-gaap:PaymentsForOriginationAndPurchasesOfLoansHeldForSale

us-gaap:PaymentsForProceedsFromLoansReceivable

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt

us-gaap:PaymentsToAcquireFederalHomeLoanBankStock

us-gaap:PaymentsToAcquireLoansHeldForInvestment
us-gaap:StatementClassOfStock
us-gaap:PreferredStockDividendRatePercentage
us-gaap:StatementClassOfStock
us-gaap:PreferredStockDividendsPerShareDeclared

us-gaap:ProceedsFromFederalHomeLoanBankAdvances

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

us-gaap:ProceedsFromNotesPayable

us-gaap:ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProceedsFromSaleOfLoansHeldForSale

us-gaap:ProfessionalFees

us-gaap:ProvisionForLoanAndLeaseLosses
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ProvisionForLoanLossesExpensed
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
us-gaap:AwardType, us-gaap:PlanName
us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod
us-gaap:TitleOfIndividual
us-gaap:StatementEquityComponents
us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensationGross

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation
us-gaap:StatementEquityComponents
us-gaap:DerivativeInstrumentRisk
mbin:DerivativeNotionalAmount1
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
mbin:FederalReserveDiscountWindowAdvancesFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
mbin:ImpairedLoansFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument
us-gaap:FairValueByMeasurementFrequency
us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument
mbin:ImpairedLoansMeasurementInputMarketabilityDiscountRate
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
mbin:InterestPayableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
mbin:InterestReceivableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

mbin:OtherAssetsAndReceivables

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis
us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost
us-gaap:FinancialInstrument
us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue

us-gaap:AvailableForSaleSecuritiesDebtSecurities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument
us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument
us-gaap:FinancialInstrument
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:CashAndCashEquivalentsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:CashAndDueFromBanks

us-gaap:CashCollateralForBorrowedSecurities

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition
us-gaap:FinancialInstrument

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss
us-gaap:FinancialInstrument

us-gaap:Deposits
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:DepositsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
us-gaap:DerivativeAssetMeasurementInput
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass
us-gaap:DerivativeAssets
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByAssetClass
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel
us-gaap:DerivativeLiabilities
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByLiabilityClass
us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType
us-gaap:DerivativeLiabilityMeasurementInput
us-gaap:DerivativeInstrumentRisk
us-gaap:DerivativeNotionalAmount
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations
us-gaap:FairValueByMeasurementBasis
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
us-gaap:FairValueByAssetClass
us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass
us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FederalHomeLoanBankBorrowingsFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:FederalHomeLoanBankStock

us-gaap:FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableCollectivelyEvaluatedForImpairment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableIndividuallyEvaluatedForImpairment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableRecordedInvestmentCurrent
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:FinancingReceivableRecordedInvestmentPastDue
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue
us-gaap:FinancingReceivablesPeriodPastDue

us-gaap:ImpairedFinancingReceivableRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableRelatedAllowance
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableUnpaidPrincipalBalance
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:InterestBearingDepositLiabilities

us-gaap:InterestBearingDepositsInBanks

us-gaap:InterestReceivable
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:InvestmentInFederalHomeLoanBankStockFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:LoansAndLeasesReceivableAllowance
us-gaap:FinancingReceivablePortfolioSegment

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome
us-gaap:FinancingReceivablePortfolioSegment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment
us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment, us-gaap:UnusualOrInfrequentItem
us-gaap:InternalCreditAssessment
us-gaap:InternalCreditAssessment, us-gaap:UnusualOrInfrequentItem

us-gaap:LoansAndLeasesReceivableNetReportedAmount

us-gaap:LoansHeldForSaleFairValueDisclosure
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementBasis
us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis
us-gaap:LoansReceivableFairValueDisclosure
us-gaap:FairValueByMeasurementBasis

us-gaap:LoansReceivableHeldForSaleNetNotPartOfDisposalGroup

us-gaap:NoninterestBearingDepositLiabilities

us-gaap:OtherLiabilities
us-gaap:StatementClassOfStock
us-gaap:PreferredStockValue

us-gaap:SecuritiesPurchasedUnderAgreementsToResell

us-gaap:ServicingAssetAtFairValueAmount
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FiniteLivedIntangibleAssetsByMajorClass
us-gaap:FairValueByMeasurementFrequency
us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FiniteLivedIntangibleAssetsByMajorClass, us-gaap:MeasurementInputType
us-gaap:ServicingAssetMeasurementInput
us-gaap:Range, us-gaap:FiniteLivedIntangibleAssetsByMajorClass, us-gaap:MeasurementInputType
dei:LegalEntity
us-gaap:TierOneLeverageCapital
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalized
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
us-gaap:ConsolidatedEntities
dei:LegalEntity
us-gaap:TierOneLeverageCapitalToAverageAssets
us-gaap:ConsolidatedEntities

us-gaap:TradingSecurities
us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency
us-gaap:FairValueByMeasurementFrequency

Tables

  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:CommonStockValue ███████████▁135.949135.746135.64135.507135.374135.19135.057135.021134.952134.941134.89128.23NANA20.061NANANA
 us-gaap:SharesOutstanding us-gaap:StatementClassOfStock,us-gaap:StatementEquityComponents mbin:PreferredStock7,us-gaap:PreferredStock▂▂▂▂█▁2.08182.08182.08182.08182.95582.0NANANANANANANANANANANANA
 us-gaap:SharesOutstanding us-gaap:StatementEquityComponents us-gaap:CommonStock███████████▁28.74561428.74248428.70643828.70643828.70643828.70416328.69403628.69403628.69403628.69220628.68516721.497667NANA21.1112NANANA
us-gaap:CommonStockSharesIssued ███████████▁28.74561428.74248428.70643828.70643828.70643828.70416328.69403628.69403628.69403628.69220628.68516721.497667NANA21.1112NANANA
us-gaap:CommonStockSharesOutstanding ███████████▁28.74561428.74248428.70643828.70643828.70643828.70416328.69403628.69403628.69403628.69220628.68516721.497667NANA21.1112NANANA
us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding █▁28.76234928.759412NA28.74495328.74629728.737439NA28.72782228.72080528.71048NA21.31835921.12792321.123257NA21.113961NANA
us-gaap:WeightedAverageNumberOfSharesOutstandingBasic █▁28.74389428.734632NA28.70643828.70531328.70225NA28.69403628.69274928.690876NA21.31019921.114421.1144NA21.1112NANA
us-gaap:EarningsPerShareBasic █▄▅▃▃▂▃▃▃▃▄▂▄▂▂▃▂▁1.310.730.920.60.510.340.510.550.520.50.730.450.660.390.380.510.360.23
us-gaap:EarningsPerShareDiluted █▄▅▃▃▂▃▃▃▃▄▂▄▂▂▃▂▁1.310.730.920.60.510.340.510.550.520.50.730.450.660.390.380.510.360.23
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:InterestAndFeeIncomeLoansAndLeases █▆▇▆▅▄▄▃▃▂▂▂▁▁▁▁63.97953.56456.82952.77942.36534.45533.99932.05628.7924.61223.10122.01619.02215.78317.69316.804NANA
us-gaap:InterestExpense ▅▆██▆▄▄▄▃▂▂▂▂▁▁▁▁▁16.9722.06426.17827.13720.83915.54315.6514.09511.9178.937.9587.6166.745.4765.5094.8574.364.242
us-gaap:InterestIncomeExpenseNet █▆▆▅▄▃▃▃▃▃▂▂▂▁▂▂▁▁51.23438.35337.62132.62427.92224.13124.17523.48222.20620.10818.95218.3915.72413.53115.18214.9712.56911.25
us-gaap:InterestPaidNet ▆▇█▆▅▄▅▄▃▂▂▂▂▁▁21.05823.78227.3721.65118.12614.74517.58213.59710.3467.7517.5057.3486.2745.6364.483NANANA
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest █▅▆▄▃▂▃▃▃▃▃▂▃▂▂▃▂▁55.39532.96439.49526.76121.76714.11121.12122.32320.83819.74521.65916.91223.84914.74114.48219.18612.6118.516
us-gaap:IncomeTaxExpenseBenefit █▅▅▄▃▂▃▃▃▃▁▄▅▃▃▄▃▂14.2338.3819.4346.5025.3283.5415.6995.5845.1864.6841.336.4459.0915.6115.7287.5874.9863.367
us-gaap:IncomeTaxesPaidNet █▁▃▂▅▁▃▄17.5860.0465.4552.49511.3120.0643.9426.948NANA9.8253.726NANA6.881NANANA
us-gaap:ProfitLoss █▄▆▃▃▁▂▃▂▂▄▁▂▁▁41.16224.58330.06120.25916.43910.5715.42216.73915.65215.06120.32910.46714.7589.138.754NANANA
us-gaap:NetIncomeLoss █▅▆▄▃▂▃▃▃▃▄▂▃▂▂▂▁▁41.16224.58330.06120.25916.43910.5715.42216.73915.65215.06120.32910.46714.7589.138.75411.5997.6255.149
us-gaap:ComprehensiveIncomeNetOfTax █▅▆▄▃▂▃▃▃▂▃▂▂▁▁▂40.94425.05129.82720.31116.92511.03416.40916.91215.74914.74319.79410.55314.6919.2688.16811.496NANA
us-gaap:PreferredStockDividendsIncomeStatementImpact ███▇▄▂▂▂▂▂▂▂▂▂▂▂▁▁3.6193.6183.6183.0221.7430.8330.8320.8330.8320.8330.8330.8330.8320.8320.8330.7620.2020.205
us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic █▄▆▄▃▂▃▃▃▃▄▂▃▂▂▂▂▁37.54320.96526.44317.23714.6969.73714.5915.90614.8214.22819.4969.63413.9268.2987.92110.8377.4234.944
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
 EBT Margin us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,mbin:BankingSegment▁█25.68329.23NANA25.98424.492NANANANANANANANANANANANA
 EBT Margin us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,mbin:MortgageWarehousing█▅▆▆▄▂▂▂▂▁▂▂▁▁▁▁42.04430.09934.88130.94621.9514.3815.93416.33514.65811.85712.49113.79512.36310.14912.12911.832NANA
 EBT Margin us-gaap:ConsolidationItems,us-gaap:StatementBusinessSegments us-gaap:OperatingSegments,mbin:MultiFamilyMortgageBanking▅█▆▆▆▆▅▄▂▃▃▂▂▁▁▂0.260.420.3280.3350.3340.3310.240.2010.1080.1630.1340.1010.1280.0510.0550.117NANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:Assets █▆▅▅▄▂▂▂▂▂▂▂▁▁▁▁9439.47908.3986371.9286337.1865287.393976.7253884.1633806.9493786.6823675.8493393.1333237.4853091.52800.6812718.5123075.098NANA
us-gaap:Liabilities █▆▄▄▃▂▂▁▁▁▁▁8731.2027235.4295718.25707.7474772.3773498.8943462.9263399.6033393.7633296.1363025.6592994.2NANA2512.224NANANA
us-gaap:LiabilitiesAndStockholdersEquity █▆▅▄▃▂▂▂▂▁▁▁9439.47908.3986371.9286337.1865287.393976.7253884.1633806.9493786.6823675.8493393.1333237.485NANA2718.512NANANA
us-gaap:StockholdersEquity █▇▇▇▅▅▄▃▃▃▃▁708.198672.969653.728629.439515.013477.831421.237407.346392.919379.713367.474243.285NANA206.288NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:CashAndCashEquivalentsAtCarryingValue ▄█▆▃▅▂▂▄▃▁▃█▄▅▅▅403.187568.082506.709364.976460.889313.451336.524410.756352.403287.733359.519566.81416.554443.56445.701456.035NANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:PropertyPlantAndEquipmentNet ████▇▆▄▃▂▁▁▁29.36229.41529.27429.21126.5821.07815.13610.8468.5846.7055.3545.138NANA4.851NANANA
us-gaap:Goodwill ▇▇▇▇▇██▂▂▂▁▂15.84515.84515.84515.57415.57417.14417.4775.3025.3695.1393.9026.037NANA0.523NANANA
us-gaap:IntangibleAssetsNetExcludingGoodwill ▄▅▆▇█▅▆▂▂▂▁3.0383.4193.7994.1824.5673.3813.5421.7631.8391.9151.512NANANANANANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:LongTermDebt █▃▂▁▁▂▂▁▂▂▁▁1761.113444.567181.439159.67362.225338.031195.45367.279189.515199.37856.61256.624NANA57.006NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:StockholdersEquity █▇▇▇▅▅▄▃▃▃▃▁708.198672.969653.728629.439515.013477.831421.237407.346392.919379.713367.474243.285NANA206.288NANANA
us-gaap:CommonStockValue ███████████▁135.949135.746135.64135.507135.374135.19135.057135.021134.952134.941134.89128.23NANA20.061NANANA
us-gaap:RetainedEarningsAccumulatedDeficit █▇▆▅▄▄▄▃▃▂▂▁358.895323.651304.984280.551265.323252.637244.909232.041217.856204.758192.008173.945NANA145.274NANANA
us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax ▇█▇▇▇▆▅▂▁▁▃▄0.7080.9260.4580.6920.640.154-0.31-1.297-1.47-1.567-1.006-0.471NANA-0.628NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▁▂█▃▂▆▇▆▇▆▅▇▆▆▇-1099.315-871.615408.004-681.64-986.1062.73998.81227.215201.326-123.763-207.555215.242-95.488-88.085273.634NANANA
us-gaap:NetCashProvidedByUsedInInvestingActivities ▁▁▄▂▆▆▆█▅▅▆▅▅▇█-562.132-568.352-258.795-445.628-149.701-103.551-131.73429.881-238.017-169.196-145.8-193.032-201.73317.42874.263NANANA
us-gaap:NetCashProvidedByUsedInFinancingActivities ██▂▆▇▃▂▂▃▃▃▃▃▃▁1496.5521501.34-7.4761031.3551283.24577.739-41.311.257101.361221.173146.064128.046270.21568.516-358.231NANANA
us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect ▁▆█▃█▄▃▆-164.89561.373141.733-95.913147.438-23.073-74.23258.353NANANANANANANANANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:NetCashProvidedByUsedInOperatingActivities ▁▂█▃▂▆▇▆▇▆▅▇▆▆▇-1099.315-871.615408.004-681.64-986.1062.73998.81227.215201.326-123.763-207.555215.242-95.488-88.085273.634NANANA
us-gaap:NetIncomeLoss █▅▆▄▃▂▃▃▃▃▄▂▃▂▂▂▁▁41.16224.58330.06120.25916.43910.5715.42216.73915.65215.06120.32910.46714.7589.138.75411.5997.6255.149
us-gaap:ProfitLoss █▄▆▃▃▁▂▃▂▂▄▁▂▁▁41.16224.58330.06120.25916.43910.5715.42216.73915.65215.06120.32910.46714.7589.138.754NANANA
us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet ▆▅▄▄▃▆▁▇▇▇▆▆███-0.849-1.379-1.481-1.536-1.915-0.798-2.942-0.37-0.371-0.309-0.769-0.671-0.047-0.003-0.144NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:NetCashProvidedByUsedInInvestingActivities ▁▁▄▂▆▆▆█▅▅▆▅▅▇█-562.132-568.352-258.795-445.628-149.701-103.551-131.73429.881-238.017-169.196-145.8-193.032-201.73317.42874.263NANANA
us-gaap:PaymentsToAcquirePropertyPlantAndEquipment ▂▂▃▄█▆▆▄▄▂▁▂▁▁▁0.4420.5941.712.6255.4424.2063.7552.3951.991.0550.0340.5360.1960.0220.026NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
us-gaap:NetCashProvidedByUsedInFinancingActivities ██▂▆▇▃▂▂▃▃▃▃▃▃▁1496.5521501.34-7.4761031.3551283.24577.739-41.311.257101.361221.173146.064128.046270.21568.516-358.231NANANA
us-gaap:PaymentsOfDividends ▆▆▅█▁▃▃▃▃▃▃▃▃▃▃5.9185.9165.6288.7840.02.8422.5542.5542.5542.5542.2661.9081.8891.8871.888NANANA
  2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31

None

us-gaap:CommonStockValue

us-gaap:CommonStockValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1351351351351351351351351341341342820
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.72.12.12.63.43.53.53.63.74.00.90.7

None

us-gaap:SharesOutstanding us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents

us-gaap:SharesOutstanding

mbin:PreferredStock7, us-gaap:PreferredStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value2.08182.08182.08182.08182.95582.0
Percentage of SharesOutstanding100.0100.0100.0100.0100.0100.0

us-gaap:SharesOutstanding us-gaap:StatementEquityComponents

us-gaap:CommonStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value282828282828282828282821212120
Percentage of SharesOutstanding1380.81380.71378.91378.9971.21435.20.00.00.00.00.00.00.00.00.0

None

us-gaap:CommonStockSharesIssued

us-gaap:CommonStockSharesIssued


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value28282828282828282828282121
Percentage of CommonStockSharesIssued100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:CommonStockSharesOutstanding

us-gaap:CommonStockSharesOutstanding


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value28282828282828282828282121
Percentage of CommonStockSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding

us-gaap:WeightedAverageNumberOfDilutedSharesOutstanding


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value282828282828282821212121
Percentage of WeightedAverageNumberOfDilutedSharesOutstanding100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic

us-gaap:WeightedAverageNumberOfSharesOutstandingBasic


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value282828282828282821212121
Percentage of WeightedAverageNumberOfSharesOutstandingBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:EarningsPerShareBasic

us-gaap:EarningsPerShareBasic


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1.310.730.920.60.510.340.510.550.520.50.730.450.660.390.380.510.360.23
Percentage of EarningsPerShareBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:EarningsPerShareDiluted

us-gaap:EarningsPerShareDiluted


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1.310.730.920.60.510.340.510.550.520.50.730.450.660.390.380.510.360.23
Percentage of EarningsPerShareDiluted100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:InterestAndFeeIncomeLoansAndLeases

us-gaap:InterestAndFeeIncomeLoansAndLeases


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value63535652423433322824232219151716
Percentage of InterestAndFeeIncomeLoansAndLeases100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating93.888.789.188.386.986.885.485.384.484.885.884.784.783.085.584.8

None

us-gaap:InterestExpense

us-gaap:InterestExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1622262720151514118.937.9587.6166.745.4765.5094.8574.364.242
Percentage of InterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating24.936.541.045.442.739.239.337.534.930.829.629.330.028.826.624.525.827.4

us-gaap:InterestExpense us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1.193-1.828-2.173-1.758-1.965-0.968-0.98-1.029-0.816-0.46-0.386-0.143-0.121-0.0860.140.318
Percentage of InterestExpense-7.0-8.3-8.3-6.5-9.4-6.2-6.3-7.3-6.8-5.2-4.9-1.9-1.8-1.62.56.5
Percentage of InterestAndDividendIncomeOperating-1.7-3.0-3.4-2.9-4.0-2.4-2.5-2.7-2.4-1.6-1.4-0.5-0.5-0.50.71.6
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations-549.8-273.70.0-340.0-398.6-205.50.0-147.0-248.0-173.60.00.00.00.00.00.0

us-gaap:InterestExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value1011118.982
Percentage of InterestExpense61.153.553.857.8
Percentage of InterestAndDividendIncomeOperating15.219.523.022.6
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment40.440.443.136.7

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value7.786121516117.5297.877.2895.4133.7973.9353.6573.4682.6133.2992.719
Percentage of InterestExpense45.954.859.659.555.648.450.351.745.442.549.448.051.547.759.956.0
Percentage of InterestAndDividendIncomeOperating11.420.024.527.023.819.019.819.415.913.114.614.115.413.715.913.7
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing18.540.20.052.252.852.40.044.636.932.00.026.528.125.70.023.0

None

us-gaap:InterestIncomeExpenseNet

us-gaap:InterestIncomeExpenseNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value513837322724242322201818151315141211
Percentage of InterestIncomeExpenseNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating75.163.559.054.657.360.860.762.565.169.270.470.770.071.273.475.574.272.6

us-gaap:InterestIncomeExpenseNet us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1.412.4962.7592.2752.4581.4391.4211.7291.1450.7251.1070.1430.1210.086-0.14-0.318
Percentage of InterestIncomeExpenseNet2.86.57.37.08.86.05.97.45.23.65.80.80.80.6-0.9-2.1
Percentage of InterestAndDividendIncomeOperating2.14.14.33.85.03.63.64.63.42.54.10.50.50.5-0.7-1.6
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations649.8373.70.0440.0498.6305.50.0247.0348.0273.60.00.00.00.00.00.0

us-gaap:InterestIncomeExpenseNet us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value15171415
Percentage of InterestIncomeExpenseNet29.945.452.964.3
Percentage of InterestAndDividendIncomeOperating22.428.830.339.1
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment59.659.656.963.3

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value34181914106.8518.0649.0469.2458.068.556108.8957.5368.839.113
Percentage of InterestIncomeExpenseNet66.947.051.345.337.128.433.438.541.640.145.155.156.655.758.260.9
Percentage of InterestAndDividendIncomeOperating50.229.830.224.721.217.320.224.127.127.831.839.039.639.642.746.0
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing81.559.80.047.847.247.60.055.463.168.00.073.571.974.30.077.0

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.260.420.3280.3350.3340.3310.240.2010.1080.1630.1340.1010.1280.0510.0550.117
Percentage of InterestIncomeExpenseNet0.51.10.91.01.21.41.00.90.50.80.70.50.80.40.40.8
Percentage of InterestAndDividendIncomeOperating0.40.70.50.60.70.80.60.50.30.60.50.40.60.30.30.6
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0100.0100.00.0100.0

None

us-gaap:InterestPaidNet

us-gaap:InterestPaidNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value2123272118141713107.7517.5057.3486.2745.6364.483
Percentage of InterestPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating30.939.442.936.237.237.244.136.230.326.727.928.327.929.721.7

None

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value55323926211421222019211623141419128.516
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating81.254.661.944.844.635.653.059.461.168.080.565.0106.277.670.096.874.555.0

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-2.728-1.663-1.109-1.361-1.171-1.826-1.71-1.2-1.52-1.594-2.003-1.467-1.114-0.961-0.948-0.98
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest-4.9-5.0-2.8-5.1-5.4-12.9-8.1-5.4-7.3-8.1-9.2-8.7-4.7-6.5-6.5-5.1
Percentage of InterestAndDividendIncomeOperating-4.0-2.8-1.7-2.3-2.4-4.6-4.3-3.2-4.5-5.5-7.4-5.6-5.0-5.1-4.6-4.9
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations-1257.1-249.00.0-263.2-237.5-387.70.0-171.4-462.0-601.50.00.00.00.00.00.0

us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value15101111
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest28.632.251.283.3
Percentage of InterestAndDividendIncomeOperating23.217.522.829.6
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment61.736.342.848.0

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value371617148.3795.1356.6767.67.466.1367.248.967.4726.1278.2478.022
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest67.150.345.453.238.536.431.634.035.831.133.453.031.341.656.941.8
Percentage of InterestAndDividendIncomeOperating54.527.528.123.817.212.916.820.221.921.126.934.533.332.239.940.5
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing88.455.10.046.038.235.70.046.550.951.80.065.060.460.40.067.8

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value5.1177.436134.0063.425-0.9556.8126.7296.5057.292104.024125.6793.1187.625
Percentage of IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest9.222.635.415.015.7-6.832.330.131.236.950.523.852.738.521.539.7
Percentage of InterestAndDividendIncomeOperating7.512.321.96.77.0-2.417.117.919.125.140.715.556.029.915.138.5
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking1968.11770.50.01195.81025.4-288.50.03347.86023.14473.60.03984.29825.011135.30.06517.1

None

us-gaap:IncomeTaxExpenseBenefit

us-gaap:IncomeTaxExpenseBenefit


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value148.3819.4346.5025.3283.5415.6995.5845.1864.6841.336.4459.0915.6115.7287.5874.9863.367
Percentage of IncomeTaxExpenseBenefit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating20.913.914.810.910.98.914.314.915.216.14.924.840.529.527.738.329.521.7

us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-0.715-0.46-0.235-0.306-0.365-0.507-0.789-0.321-0.148-0.561-0.567-0.559-0.425-0.366-0.374-0.389
Percentage of IncomeTaxExpenseBenefit-5.0-5.5-2.5-4.7-6.9-14.3-13.8-5.7-2.9-12.0-42.6-8.7-4.7-6.5-6.5-5.1
Percentage of InterestAndDividendIncomeOperating-1.0-0.8-0.4-0.5-0.7-1.3-2.0-0.9-0.4-1.9-2.1-2.1-1.9-1.9-1.8-2.0
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations-329.5-68.90.0-59.2-74.0-107.60.0-45.9-45.0-211.70.00.00.00.00.00.0

us-gaap:IncomeTaxExpenseBenefit us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value4.0312.652.7262.988
Percentage of IncomeTaxExpenseBenefit28.331.651.284.4
Percentage of InterestAndDividendIncomeOperating5.94.45.67.5
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment15.79.110.512.2

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value9.4514.1544.2523.322.0591.3031.7341.9461.6861.5062.9633.4142.8492.3323.2623.173
Percentage of IncomeTaxExpenseBenefit66.449.645.151.138.636.830.434.832.532.2222.853.031.341.656.941.8
Percentage of InterestAndDividendIncomeOperating13.96.96.75.64.23.34.45.24.95.211.013.112.712.315.816.0
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing22.513.80.010.79.49.10.011.911.512.70.024.723.023.00.026.8

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1.4662.0373.7611.2650.908-0.2432.1141.8661.741.808-3.9321.5344.7932.1621.2333.015
Percentage of IncomeTaxExpenseBenefit10.324.339.919.517.0-6.937.133.433.638.6-295.623.852.738.521.539.7
Percentage of InterestAndDividendIncomeOperating2.13.45.92.11.9-0.65.35.05.16.2-14.65.921.311.46.015.2
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking563.8485.00.0377.6271.9-73.40.0928.41611.11109.20.01518.83744.54239.20.02576.9

None

us-gaap:IncomeTaxesPaidNet

us-gaap:IncomeTaxesPaidNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302017-12-312017-09-302016-12-31
Value170.0465.4552.495110.0643.9426.9489.8253.7266.881
Percentage of IncomeTaxesPaidNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating25.80.18.64.223.20.29.918.536.514.333.3

None

us-gaap:ProfitLoss

us-gaap:ProfitLoss


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value412430201610151615152010149.138.754
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.747.133.933.726.638.744.545.951.975.540.265.748.042.3

None

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value412430201610151615152010149.138.754117.6255.149
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.747.133.933.726.638.744.545.951.975.540.265.748.042.358.545.033.2

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-2.013-1.203-0.874-1.055-0.806-1.319-0.921-0.879-1.372-1.033-1.436-0.908-0.689-0.595-0.574-0.591
Percentage of NetIncomeLoss-4.9-4.9-2.9-5.2-4.9-12.5-6.0-5.3-8.8-6.9-7.1-8.7-4.7-6.5-6.6-5.1
Percentage of InterestAndDividendIncomeOperating-3.0-2.0-1.4-1.8-1.7-3.3-2.3-2.3-4.0-3.6-5.3-3.5-3.1-3.1-2.8-3.0
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations-927.6-180.10.0-204.1-163.5-280.00.0-125.6-417.0-389.80.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value117.958.4088.769
Percentage of NetIncomeLoss28.732.351.183.0
Percentage of InterestAndDividendIncomeOperating17.313.217.222.1
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment46.027.232.435.8

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value271213106.323.8324.9425.6545.7744.634.2775.5464.6233.7954.9854.849
Percentage of NetIncomeLoss67.350.645.553.938.436.332.033.836.930.721.053.031.341.656.941.8
Percentage of InterestAndDividendIncomeOperating40.620.621.518.313.09.712.415.016.915.915.921.320.620.024.124.5
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing65.941.30.035.328.826.60.034.639.439.00.040.237.437.40.041.0

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.6515.399102.7412.517-0.7124.6984.8634.7655.484142.497.7833.5171.8854.61
Percentage of NetIncomeLoss8.922.034.013.515.3-6.730.529.130.436.473.223.852.738.521.539.7
Percentage of InterestAndDividendIncomeOperating5.48.916.04.65.2-1.811.812.914.018.955.39.634.618.59.123.3
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking1404.21285.50.0818.2753.6-215.10.02419.44412.03364.40.02465.36080.56896.10.03940.2

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value41242016101516151520
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.733.933.726.638.744.545.951.975.5
Percentage of InterestAndDividendIncomeOperating us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.0

None

us-gaap:ComprehensiveIncomeNetOfTax

us-gaap:ComprehensiveIncomeNetOfTax


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value402529201611161615141910149.2688.16811
Percentage of ComprehensiveIncomeNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.041.546.834.034.727.841.245.046.250.873.640.665.448.839.558.0

None

us-gaap:PreferredStockDividendsIncomeStatementImpact

us-gaap:PreferredStockDividendsIncomeStatementImpact


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value3619000.03618000.03618000.03022000.01743000.0833000.0832000.0833000.0832000.0833000.0833000.0833000.0832000.0832000.0833000.0762000.0202000.0205000.0
Percentage of PreferredStockDividendsIncomeStatementImpact100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating5.36.05.75.13.62.12.12.22.42.93.13.23.74.44.03.81.21.3

None

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic

us-gaap:NetIncomeLossAvailableToCommonStockholdersBasic


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value37202617149.73714151414199.634138.2987.921107.4234.944
Percentage of NetIncomeLossAvailableToCommonStockholdersBasic100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating55.034.741.428.830.124.536.642.343.449.072.437.062.043.738.354.743.831.9

None

us-gaap:Assets

us-gaap:Assets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value94397908637163375287397638843806378636753393323730912800271830752269
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value4241394248373020192116-54.505131013-20.4784.121
Percentage of Assets0.50.50.60.70.91.00.80.50.50.60.5-1.70.40.40.5-0.70.2
Percentage of Assets0.50.50.60.70.91.00.80.50.50.60.5-1.70.40.40.5-0.70.2
Percentage of Assets mbin:CorporateReconcilingItemsAndEliminations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:Assets us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-12-312019-06-302019-03-312018-12-312017-12-31
Value3639332330182412222322561889
Percentage of Assets38.642.047.445.655.958.155.7
Percentage of Assets38.642.047.445.655.958.155.7
Percentage of Assets us-gaap:OperatingSegments mbin:BankingSegment100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value5575436231243529266115541430162415501603135211921288104810601368924
Percentage of Assets59.155.249.055.750.339.136.842.740.943.639.936.841.737.439.044.540.7
Percentage of Assets59.155.249.055.750.339.136.842.740.943.639.936.841.737.439.044.540.7
Percentage of Assets us-gaap:OperatingSegments mbin:MortgageWarehousing100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-31
Value1821801881691641601661521461411341351171049810087
Percentage of Assets1.92.33.02.73.14.04.34.03.93.94.04.23.83.73.63.33.8
Percentage of Assets1.92.33.02.73.14.04.34.03.93.94.04.23.83.73.63.33.8
Percentage of Assets us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:Liabilities

us-gaap:Liabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value8731723557185707477234983462339933933296302529942512
Percentage of Liabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets92.591.589.790.190.388.089.289.389.689.789.292.592.4

None

us-gaap:LiabilitiesAndStockholdersEquity

us-gaap:LiabilitiesAndStockholdersEquity


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9439790863716337528739763884380637863675339332372718
Percentage of LiabilitiesAndStockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value708672653629515477421407392379367243206148110
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.58.510.39.99.712.010.810.710.410.310.87.57.66.50.0

us-gaap:StockholdersEquity us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents

mbin:PreferredStock6, us-gaap:PreferredStock


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value120120120120
Percentage of StockholdersEquity17.118.018.519.2
Percentage of Assets1.31.51.91.9
Percentage of Assets mbin:PreferredStock6 us-gaap:PreferredStock0.00.00.00.0

mbin:PreferredStock7, us-gaap:PreferredStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value505050507248
Percentage of StockholdersEquity7.17.57.78.014.010.1
Percentage of Assets0.50.60.80.81.41.2
Percentage of Assets mbin:PreferredStock7 us-gaap:PreferredStock0.00.00.00.00.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value0.7080.9260.4580.6920.640.154-0.31-1.297-1.47-1.567-1.006-0.471-0.628-0.232-0.193
Percentage of StockholdersEquity0.10.10.10.10.10.0-0.1-0.3-0.4-0.4-0.3-0.2-0.3-0.2-0.2
Percentage of Assets0.00.00.00.00.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value13513513513513513513513513413413428202016
Percentage of StockholdersEquity19.220.220.721.526.328.332.133.134.335.536.711.69.713.514.6
Percentage of Assets1.41.72.12.12.63.43.53.53.63.74.00.90.70.90.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value35832330428026525224423221720419217314511894
Percentage of StockholdersEquity50.748.146.744.651.552.958.157.055.453.952.371.570.479.985.5
Percentage of Assets3.84.14.84.45.06.46.36.15.85.65.75.45.35.20.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

None

us-gaap:CashAndCashEquivalentsAtCarryingValue

us-gaap:CashAndCashEquivalentsAtCarryingValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302015-12-312014-12-31
Value403568506364460313336410352287359566416443445456446229
Percentage of CashAndCashEquivalentsAtCarryingValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets4.37.28.05.88.77.98.710.89.37.810.617.513.515.816.414.819.70.0

None

us-gaap:PropertyPlantAndEquipmentNet

us-gaap:PropertyPlantAndEquipmentNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value29292929262115108.5846.7055.3545.1384.851
Percentage of PropertyPlantAndEquipmentNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.30.40.50.50.50.50.40.30.20.20.20.20.2

None

us-gaap:Goodwill

us-gaap:Goodwill


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value151515151517175.3025.3695.1393.9026.0370.5230.5230.523
Percentage of Goodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.20.20.20.20.30.40.40.10.10.10.10.20.00.00.0

None

us-gaap:IntangibleAssetsNetExcludingGoodwill

us-gaap:IntangibleAssetsNetExcludingGoodwill


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value3038000.03419000.03799000.04182000.04567000.03381000.03542000.01763000.01839000.01915000.01512000.0
Percentage of IntangibleAssetsNetExcludingGoodwill100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.10.10.10.10.10.00.00.10.0

None

us-gaap:LongTermDebt

us-gaap:LongTermDebt


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value17614441811596233819567189199565657
Percentage of LongTermDebt100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets18.75.62.82.51.28.55.01.85.05.41.71.72.1

None

us-gaap:StockholdersEquity

us-gaap:StockholdersEquity


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value708672653629515477421407392379367243206148110
Percentage of StockholdersEquity100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets7.58.510.39.99.712.010.810.710.410.310.87.57.66.50.0

us-gaap:StockholdersEquity us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents

mbin:PreferredStock6, us-gaap:PreferredStock


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value120120120120
Percentage of StockholdersEquity17.118.018.519.2
Percentage of Assets1.31.51.91.9
Percentage of Assets mbin:PreferredStock6 us-gaap:PreferredStock0.00.00.00.0

mbin:PreferredStock7, us-gaap:PreferredStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-31
Value505050507248
Percentage of StockholdersEquity7.17.57.78.014.010.1
Percentage of Assets0.50.60.80.81.41.2
Percentage of Assets mbin:PreferredStock7 us-gaap:PreferredStock0.00.00.00.00.00.0

us-gaap:StockholdersEquity us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value0.7080.9260.4580.6920.640.154-0.31-1.297-1.47-1.567-1.006-0.471-0.628-0.232-0.193
Percentage of StockholdersEquity0.10.10.10.10.10.0-0.1-0.3-0.4-0.4-0.3-0.2-0.3-0.2-0.2
Percentage of Assets0.00.00.00.00.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0-0.00.0
Percentage of Assets us-gaap:AccumulatedOtherComprehensiveIncome0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:CommonStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value13513513513513513513513513413413428202016
Percentage of StockholdersEquity19.220.220.721.526.328.332.133.134.335.536.711.69.713.514.6
Percentage of Assets1.41.72.12.12.63.43.53.53.63.74.00.90.70.90.0
Percentage of Assets us-gaap:CommonStock0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value35832330428026525224423221720419217314511894
Percentage of StockholdersEquity50.748.146.744.651.552.958.157.055.453.952.371.570.479.985.5
Percentage of Assets3.84.14.84.45.06.46.36.15.85.65.75.45.35.20.0
Percentage of Assets us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.00.00.00.00.00.0

None

us-gaap:CommonStockValue

us-gaap:CommonStockValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1351351351351351351351351341341342820
Percentage of CommonStockValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets1.41.72.12.12.63.43.53.53.63.74.00.90.7

None

us-gaap:RetainedEarningsAccumulatedDeficit

us-gaap:RetainedEarningsAccumulatedDeficit


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value358323304280265252244232217204192173145
Percentage of RetainedEarningsAccumulatedDeficit100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets3.84.14.84.45.06.46.36.15.85.65.75.45.3

None

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax

us-gaap:AccumulatedOtherComprehensiveIncomeLossNetOfTax


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value708000.0926000.0458000.0692000.0640000.0154000.0-310000.0-1297000.0-1470000.0-1567000.0-1006000.0-471000.0-628000.0
Percentage of AccumulatedOtherComprehensiveIncomeLossNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of Assets0.00.00.00.00.00.0-0.0-0.0-0.0-0.0-0.0-0.0-0.0

None

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-1099.315-871.615408-681.64-986.1062.7399827201-123.763-207.555215-95.488-88.085273
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-1611.8-1442.7639.5-1140.6-2022.36.9248.172.4590.0-426.2-771.3827.7-425.1-463.41322.5

None

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-562.132-568.352-258.795-445.628-149.701-103.551-131.73429-238.017-169.196-145.8-193.032-201.7331774
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-824.2-940.7-405.6-745.7-307.0-261.0-330.879.5-697.5-582.7-541.8-742.3-898.091.7358.9

None

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value14961501-7.4761031128377-41.311.25710122114612827068-358.231
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating2194.22485.0-11.71725.82631.7195.9-103.73.3297.0761.7542.8492.41202.9360.5-1731.3

None

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect

us-gaap:CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value-164.89561141-95.913147-23.073-74.23258
Percentage of CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-241.8101.6222.2-160.5302.4-58.2-186.4155.3

None

us-gaap:NetCashProvidedByUsedInOperatingActivities

us-gaap:NetCashProvidedByUsedInOperatingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-1099.315-871.615408-681.64-986.1062.7399827201-123.763-207.555215-95.488-88.085273
Percentage of NetCashProvidedByUsedInOperatingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-1611.8-1442.7639.5-1140.6-2022.36.9248.172.4590.0-426.2-771.3827.7-425.1-463.41322.5

None

us-gaap:NetIncomeLoss

us-gaap:NetIncomeLoss


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value412430201610151615152010149.138.754117.6255.149
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.747.133.933.726.638.744.545.951.975.540.265.748.042.358.545.033.2

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-2.013-1.203-0.874-1.055-0.806-1.319-0.921-0.879-1.372-1.033-1.436-0.908-0.689-0.595-0.574-0.591
Percentage of NetIncomeLoss-4.9-4.9-2.9-5.2-4.9-12.5-6.0-5.3-8.8-6.9-7.1-8.7-4.7-6.5-6.6-5.1
Percentage of InterestAndDividendIncomeOperating-3.0-2.0-1.4-1.8-1.7-3.3-2.3-2.3-4.0-3.6-5.3-3.5-3.1-3.1-2.8-3.0
Percentage of InterestAndDividendIncomeOperating mbin:CorporateReconcilingItemsAndEliminations-927.6-180.10.0-204.1-163.5-280.00.0-125.6-417.0-389.80.00.00.00.00.00.0

us-gaap:NetIncomeLoss us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value117.958.4088.769
Percentage of NetIncomeLoss28.732.351.183.0
Percentage of InterestAndDividendIncomeOperating17.313.217.222.1
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:BankingSegment46.027.232.435.8

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value271213106.323.8324.9425.6545.7744.634.2775.5464.6233.7954.9854.849
Percentage of NetIncomeLoss67.350.645.553.938.436.332.033.836.930.721.053.031.341.656.941.8
Percentage of InterestAndDividendIncomeOperating40.620.621.518.313.09.712.415.016.915.915.921.320.620.024.124.5
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MortgageWarehousing65.941.30.035.328.826.60.034.639.439.00.040.237.437.40.041.0

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.6515.399102.7412.517-0.7124.6984.8634.7655.484142.497.7833.5171.8854.61
Percentage of NetIncomeLoss8.922.034.013.515.3-6.730.529.130.436.473.223.852.738.521.539.7
Percentage of InterestAndDividendIncomeOperating5.48.916.04.65.2-1.811.812.914.018.955.39.634.618.59.123.3
Percentage of InterestAndDividendIncomeOperating us-gaap:OperatingSegments mbin:MultiFamilyMortgageBanking1404.21285.50.0818.2753.6-215.10.02419.44412.03364.40.02465.36080.56896.10.03940.2

us-gaap:NetIncomeLoss us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value41242016101516151520
Percentage of NetIncomeLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.733.933.726.638.744.545.951.975.5
Percentage of InterestAndDividendIncomeOperating us-gaap:RetainedEarnings0.00.00.00.00.00.00.00.00.00.0

None

us-gaap:ProfitLoss

us-gaap:ProfitLoss


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value412430201610151615152010149.138.754
Percentage of ProfitLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating60.440.747.133.933.726.638.744.545.951.975.540.265.748.042.3

None

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet

us-gaap:IncreaseDecreaseInOtherOperatingCapitalNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-849000.0-1379000.0-1481000.0-1536000.0-1915000.0-798000.0-2942000.0-370000.0-371000.0-309000.0-769000.0-671000.0-47000.0-3000.0-144000.0
Percentage of IncreaseDecreaseInOtherOperatingCapitalNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:NetCashProvidedByUsedInInvestingActivities

us-gaap:NetCashProvidedByUsedInInvestingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-562.132-568.352-258.795-445.628-149.701-103.551-131.73429-238.017-169.196-145.8-193.032-201.7331774
Percentage of NetCashProvidedByUsedInInvestingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating-824.2-940.7-405.6-745.7-307.0-261.0-330.879.5-697.5-582.7-541.8-742.3-898.091.7358.9

None

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment

us-gaap:PaymentsToAcquirePropertyPlantAndEquipment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value0.4420.5941.712.6255.4424.2063.7552.3951.991.0550.0340.5360.1960.0220.026
Percentage of PaymentsToAcquirePropertyPlantAndEquipment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

None

us-gaap:NetCashProvidedByUsedInFinancingActivities

us-gaap:NetCashProvidedByUsedInFinancingActivities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value14961501-7.4761031128377-41.311.25710122114612827068-358.231
Percentage of NetCashProvidedByUsedInFinancingActivities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0
Percentage of InterestAndDividendIncomeOperating2194.22485.0-11.71725.82631.7195.9-103.73.3297.0761.7542.8492.41202.9360.5-1731.3

None

us-gaap:PaymentsOfDividends

us-gaap:PaymentsOfDividends


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value5.9185.9165.6288.7840.02.8422.5542.5542.5542.5542.2661.9081.8891.8871.888
Percentage of PaymentsOfDividends100.0100.0100.0100.00.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:Dividends6PercentPreferredStock

mbin:Dividends6PercentPreferredStock


None
Period End2020-06-302020-03-312019-09-30
Value1875000.01875000.0896000.0
Percentage of Dividends6PercentPreferredStock100.0100.0100.0

mbin:Dividends6PercentPreferredStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-30
Value1875000.01875000.0896000.0
Percentage of Dividends6PercentPreferredStock100.0100.0100.0

mbin:Dividends7PercentPreferredStock

mbin:Dividends7PercentPreferredStock


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value911000.0910000.01293000.0911000.0
Percentage of Dividends7PercentPreferredStock100.0100.0100.0100.0

mbin:Dividends7PercentPreferredStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value911000.0910000.01293000.0911000.0
Percentage of Dividends7PercentPreferredStock100.0100.0100.0100.0

mbin:Dividends8PercentPreferredStock

mbin:Dividends8PercentPreferredStock


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value833000.0833000.0833000.0832000.0833000.0833000.0832000.0833000.0
Percentage of Dividends8PercentPreferredStock100.0100.0100.0100.0100.0100.0100.0100.0

mbin:Dividends8PercentPreferredStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value833000.0833000.0833000.0832000.0833000.0833000.0832000.0833000.0
Percentage of Dividends8PercentPreferredStock100.0100.0100.0100.0100.0100.0100.0100.0

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetChangesInValuationInputsOrAssumptionsUsedInValuationModel us-gaap:FairValueByAssetClass

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetChangesInValuationInputsOrAssumptionsUsedInValuationModel

us-gaap:Assets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value-500000.0-6480000.01070000.0-1479000.0-2881000.0-1505000.0435000.0500000.01806000.0-893000.03739000.0-1437000.0561000.087000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetChangesInValuationInputsOrAssumptionsUsedInValuationModel100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOriginatedAndPurchasedServicing us-gaap:FairValueByAssetClass

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOriginatedAndPurchasedServicing

us-gaap:Assets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value4.0153.9292.6951.3562.2611.026.8481.5632.253.4522.0093.015
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetOriginatedAndPurchasedServicing100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydown us-gaap:FairValueByAssetClass

mbin:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydown

us-gaap:Assets


None
Period End2020-06-302020-03-312019-06-302019-03-312018-03-31
Value-604000.0-1858000.0-1079000.0-1110000.0-1370000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPaydown100.0100.0100.0100.0100.0

mbin:GainLossOnSaleOfAvailableForSaleInvestmentsAmountRelatedToAociReclassification

mbin:GainLossOnSaleOfAvailableForSaleInvestmentsAmountRelatedToAociReclassification


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value00352000.00-3000.0127000.00000
Percentage of GainLossOnSaleOfAvailableForSaleInvestmentsAmountRelatedToAociReclassification0.00.0100.00.0100.0100.00.00.00.00.0

mbin:IncomeTaxExpenseBenefitRelatedToReclassificationItems

mbin:IncomeTaxExpenseBenefitRelatedToReclassificationItems


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-30
Value00-86000.001000.032000.0000000010000.0
Percentage of IncomeTaxExpenseBenefitRelatedToReclassificationItems0.00.0100.00.0100.0100.00.00.00.00.00.00.00.0100.0

mbin:ServicingFeesAmount

mbin:ServicingFeesAmount


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value1597000.0-5824000.02200000.0-1410000.0-1561000.0-347000.01657000.01851000.02555000.0-322000.03972000.0-83000.0395000.01989000.0
Percentage of ServicingFeesAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForLoanAndLeaseLossRecoveryOfBadDebts

us-gaap:AllowanceForLoanAndLeaseLossRecoveryOfBadDebts


None
Period End2020-03-312019-06-302019-03-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value44000.003000.036000.031000.05000.00075000.060000.0
Percentage of AllowanceForLoanAndLeaseLossRecoveryOfBadDebts100.00.0100.0100.0100.0100.00.00.0100.0100.0

us-gaap:AllowanceForLoanAndLeaseLossRecoveryOfBadDebts us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-03-312018-09-302018-06-302017-12-312017-09-302017-06-302017-03-31
Value44000.01000.01000.034000.0075000.026000.0
Percentage of AllowanceForLoanAndLeaseLossRecoveryOfBadDebts100.02.83.20.00.0100.043.3

us-gaap:AllowanceForLoanAndLeaseLossesWriteOffs

us-gaap:AllowanceForLoanAndLeaseLossesWriteOffs


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302018-03-31
Value-131000.0-1000.00-107000.0-857000.0-147000.074000.0-146000.0-17000.0
Percentage of AllowanceForLoanAndLeaseLossesWriteOffs100.0100.00.0100.0100.0100.0100.0100.0100.0

us-gaap:AllowanceForLoanAndLeaseLossesWriteOffs us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302019-12-312019-09-302019-06-302018-12-312018-09-302018-06-30
Value-131000.0-3000.00-854000.0-1000.046000.0-135000.0
Percentage of AllowanceForLoanAndLeaseLossesWriteOffs100.00.0-0.099.60.762.292.5

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312018-09-302018-06-302018-03-31
Value0-1000.028000.0-11000.0-17000.0
Percentage of AllowanceForLoanAndLeaseLossesWriteOffs-0.0100.037.87.5100.0

us-gaap:AmortizationOfMortgageServicingRightsMSRs

us-gaap:AmortizationOfMortgageServicingRightsMSRs


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value1.1048.3380.2973.9173.962.6150.4940.158-0.5672.263-2.0482.521.8830.1994.41
Percentage of AmortizationOfMortgageServicingRightsMSRs100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommonStockDividendsPerShareDeclared

us-gaap:CommonStockDividendsPerShareDeclared


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.320.320.070.070.070.060.060.060.060.05
Percentage of CommonStockDividendsPerShareDeclared100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CommunicationsAndInformationTechnology

us-gaap:CommunicationsAndInformationTechnology


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value716000.0610000.0848000.0674000.0629000.0472000.0548000.0412000.0293000.0291000.0340000.0325000.0261000.0245000.0288000.0276000.0
Percentage of CommunicationsAndInformationTechnology100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DebtSecuritiesTradingUnrealizedGainLoss

us-gaap:DebtSecuritiesTradingUnrealizedGainLoss


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value1400000.02200000.0399000.0545000.0
Percentage of DebtSecuritiesTradingUnrealizedGainLoss100.0100.0100.0100.0

us-gaap:Depreciation

us-gaap:Depreciation


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value462000.0453000.0416000.0151000.0148000.0137000.0125000.0123000.0110000.0103000.095000.070000.064000.067000.069000.0
Percentage of Depreciation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeGainLossOnDerivativeNet

us-gaap:DerivativeGainLossOnDerivativeNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1629000.0-31000.0-75000.0119000.024000.0-5000.014000.0-79000.0-148000.0219000.0
Percentage of DerivativeGainLossOnDerivativeNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DerivativeGainLossOnDerivativeNet us-gaap:DerivativeInstrumentRisk

us-gaap:ForwardContracts


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-2114000.0-1844000.027000.0-25000.0-50000.0-5000.012000.016000.0-197000.0105000.0
Percentage of DerivativeGainLossOnDerivativeNet-129.85948.4-36.0-21.0-208.3100.085.7-20.3133.147.9

us-gaap:InterestRateLockCommitments


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302018-03-31
Value3743000.01813000.0-102000.0144000.074000.02000.0-95000.049000.0114000.0
Percentage of DerivativeGainLossOnDerivativeNet229.8-5848.4136.0121.0308.314.3120.3-33.152.1

us-gaap:DerivativeGainOnDerivative us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeGainOnDerivative

us-gaap:InterestRateSwap


None
Period End2020-06-30
Value634000.0
Percentage of DerivativeGainOnDerivative100.0

us-gaap:DerivativeLossOnDerivative us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeLossOnDerivative

us-gaap:InterestRateSwap


None
Period End2020-06-30
Value634000.0
Percentage of DerivativeLossOnDerivative100.0

us-gaap:DividendsCommonStock

us-gaap:DividendsCommonStock


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2299000.02298000.02009000.02010000.02009000.01722000.01721000.01722000.01721000.01434000.0
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DividendsCommonStock us-gaap:StatementEquityComponents

us-gaap:RetainedEarnings


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2299000.02298000.02009000.02010000.02009000.01722000.01721000.01722000.01721000.01434000.0
Percentage of DividendsCommonStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3663000.01893000.0-110000.0149000.076000.01000.02000.0-102000.054000.0116000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-30
Value-80000.080000.05000.02000.01000.0-7000.05000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings100.0100.0100.0100.0100.0100.0100.0

us-gaap:FederalDepositInsuranceCorporationPremiumExpense

us-gaap:FederalDepositInsuranceCorporationPremiumExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1851000.01786000.01393000.0859000.0218000.0277000.0273000.0269000.0236000.0246000.0226000.0230000.0210000.0264000.0235000.0324000.0
Percentage of FederalDepositInsuranceCorporationPremiumExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FeesAndCommissionsMortgageBankingAndServicing

us-gaap:FeesAndCommissionsMortgageBankingAndServicing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value5475000.02746000.02555000.02699000.01138000.0753000.0602000.0778000.0684000.0486000.0601000.0749000.0662000.0596000.0
Percentage of FeesAndCommissionsMortgageBankingAndServicing100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:GainLossOnSalesOfLoansNet

us-gaap:GainLossOnSalesOfLoansNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1721158.3129.1042.643118.8257.831109.9777.204155.4427.64610
Percentage of GainLossOnSalesOfLoansNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableAverageRecordedInvestment

us-gaap:ImpairedFinancingReceivableAverageRecordedInvestment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value14141312129.7089.4859.5663.6464.845.523.148
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableAverageRecordedInvestment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-31
Value2.0922.0430.2140.3140.3640.4250.6340.6350.2820.2430.203
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment14.513.71.52.53.04.46.76.67.75.03.7

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.1710.2310.2390.5680.5740.6910.7741.352
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment1.21.61.74.54.77.18.214.1

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value9.2299.5028.2647.6598.4687.2546.6746.5873.1334.2714.9743.014
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment64.063.859.460.469.174.770.468.985.988.290.195.7

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value0.0170.020.0260.0520.0480.1870.1960.146
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment0.10.10.20.40.41.92.11.5

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-312017-09-302017-06-302017-03-312016-09-30
Value2.9163.0885.1724.0912.8061.0421.0950.7290.2310.3260.3430.134
Percentage of ImpairedFinancingReceivableAverageRecordedInvestment20.220.737.232.322.910.711.57.66.36.76.24.3

us-gaap:ImpairedFinancingReceivableInterestIncomeCashBasisMethod

us-gaap:ImpairedFinancingReceivableInterestIncomeCashBasisMethod


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value113000.0147000.096000.0136000.0164000.0155000.0182000.0155000.0191000.071000.0162000.011000.0-21000.031000.029000.010000.0
Percentage of ImpairedFinancingReceivableInterestIncomeCashBasisMethod100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableInterestIncomeCashBasisMethod us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value94000.0131000.088000.0127000.0118000.0140000.0198000.098000.079000.046000.0161000.011000.0-20000.030000.029000.010000.0
Percentage of ImpairedFinancingReceivableInterestIncomeCashBasisMethod83.289.191.793.472.090.3108.863.241.464.899.4100.095.296.8100.0100.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-03-31
Value19000.016000.09000.09000.045000.015000.0-1000.021000.030000.03000.01000.0
Percentage of ImpairedFinancingReceivableInterestIncomeCashBasisMethod16.810.99.46.627.49.7-0.513.515.74.23.2

us-gaap:IncreaseDecreaseInDeposits

us-gaap:IncreaseDecreaseInDeposits


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value1851244-21.5738431534-110.031-166.929126113824212927270-356.331
Percentage of IncreaseDecreaseInDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingAssets

us-gaap:IncreaseDecreaseInOtherOperatingAssets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-0.31517-1.176-1.659.188-2.6995.3050.4460.8653.4070.003-0.614-12.0171.1274.282
Percentage of IncreaseDecreaseInOtherOperatingAssets100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities

us-gaap:IncreaseDecreaseInOtherOperatingLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value-6.6149.82214-2.168101.933-0.0221.581-6.0587.918-4.7-6.3585.9194.289-2.647
Percentage of IncreaseDecreaseInOtherOperatingLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncreaseDecreaseInTradingSecurities

us-gaap:IncreaseDecreaseInTradingSecurities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value5319541126-28.4-33.50589-60.959-64.9555919-23.696-36.77844-82.423
Percentage of IncreaseDecreaseInTradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements

us-gaap:IncrementalCommonSharesAttributableToShareBasedPaymentArrangements


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value18455.024780.02353.038515.040984.035189.04315.033786.028056.019604.010642.08160.013523.08857.0585.02761.0
Percentage of IncrementalCommonSharesAttributableToShareBasedPaymentArrangements100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestAndDividendIncomeOperating

us-gaap:InterestAndDividendIncomeOperating


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value686063594839393734292626221920191615
Percentage of InterestAndDividendIncomeOperating100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestAndDividendIncomeOperating us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.2170.6680.5860.5170.4930.4710.4410.70.3290.265
Percentage of InterestAndDividendIncomeOperating0.31.10.90.91.01.21.11.91.00.9

us-gaap:InterestAndDividendIncomeOperating us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value25292524
Percentage of InterestAndDividendIncomeOperating37.748.453.361.7

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value42303430211415161411121312101211
Percentage of InterestAndDividendIncomeOperating61.649.854.751.845.036.240.043.543.040.846.453.055.053.458.659.7

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.260.420.3280.3350.3340.3310.240.2010.1080.1630.1340.1010.1280.0510.0550.117
Percentage of InterestAndDividendIncomeOperating0.40.70.50.60.70.80.60.50.30.60.50.40.60.30.30.6

us-gaap:InterestExpenseBorrowings

us-gaap:InterestExpenseBorrowings


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1572000.01434000.01127000.01098000.01495000.01316000.01861000.02425000.02176000.01914000.02125000.01957000.02000000.01705000.01822000.01841000.0
Percentage of InterestExpenseBorrowings100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestExpenseDeposits

us-gaap:InterestExpenseDeposits


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value15202526191413119.7417.0165.8335.6594.743.7713.6873.016
Percentage of InterestExpenseDeposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeDebtSecuritiesTradingOperating

us-gaap:InterestIncomeDebtSecuritiesTradingOperating


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value2534000.02796000.01967000.01045000.0
Percentage of InterestIncomeDebtSecuritiesTradingOperating100.0100.0100.0100.0

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value493535312723222221181717151314141211
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1.412.4962.7592.2752.4581.4391.4211.7291.1450.7251.1070.1430.1210.086-0.14-0.318
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss2.87.17.77.28.86.16.37.65.43.96.30.80.80.6-0.9-2.2

us-gaap:InterestIncomeExpenseAfterProvisionForLoanLoss us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value12151414
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss25.844.153.963.9

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value35161814106.7187.8778.8198.9617.3868.354108.7377.2899.3029.174
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss70.847.652.845.736.028.634.938.642.339.547.657.856.454.862.362.3

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.260.420.3280.3350.3340.3310.240.2010.1080.1630.1340.1010.1280.0510.0550.117
Percentage of InterestIncomeExpenseAfterProvisionForLoanLoss0.51.20.91.11.21.41.10.90.50.90.80.60.80.40.40.8

us-gaap:InterestIncomeFederalHomeLoanBankAdvances

us-gaap:InterestIncomeFederalHomeLoanBankAdvances


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value447000.0239000.0190000.0262000.0257000.0223000.088000.087000.081000.0129000.081000.080000.079000.081000.080000.080000.0
Percentage of InterestIncomeFederalHomeLoanBankAdvances100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeOther

us-gaap:InterestIncomeOther


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value0.2342.4592.8933.6262.6422.3042.7632.5942.1381.7661.3091.3510.8930.8730.5610.602
Percentage of InterestIncomeOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestIncomeSecuritiesTaxExempt

us-gaap:InterestIncomeSecuritiesTaxExempt


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-31
Value38000.037000.068000.053000.096000.0
Percentage of InterestIncomeSecuritiesTaxExempt100.0100.0100.0100.0100.0

us-gaap:InterestIncomeSecuritiesTaxable

us-gaap:InterestIncomeSecuritiesTaxable


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value972000.01322000.01576000.01604000.01477000.01551000.01740000.01541000.01625000.01542000.0
Percentage of InterestIncomeSecuritiesTaxable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LaborAndRelatedExpense

us-gaap:LaborAndRelatedExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1114109.1399.9658.567107.8427.2686.4877.0555.355.1753.8924.2443.798
Percentage of LaborAndRelatedExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoanPortfolioExpense

us-gaap:LoanPortfolioExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2039000.01164000.01007000.01248000.01345000.0934000.01109000.01254000.01302000.0956000.01025000.01119000.01069000.0884000.01174000.01171000.0
Percentage of LoanPortfolioExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestExpense

us-gaap:NoninterestExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value20221815151316121210108.9428.2616.6417.3847.1736.3765.787
Percentage of NoninterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestExpense us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.1963.2383.1822.8972.9412.6022.6172.3652.1331.9832.2961.611.2351.0470.8080.662
Percentage of NoninterestExpense15.814.516.918.718.520.016.219.017.819.321.318.014.915.810.99.2

us-gaap:NoninterestExpense us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value6.0975.6884.8624.12
Percentage of NoninterestExpense30.125.530.531.6

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value3.5213.0193.4422.8292.792.3361.8021.9982.1851.7361.8712.1091.9431.7872.2072.042
Percentage of NoninterestExpense17.413.518.318.217.517.911.116.018.216.917.323.623.526.929.928.5

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value7.468107.1646.0885.3273.9777.2594.3464.2183.3823.8262.7132.7771.5952.3252.012
Percentage of NoninterestExpense36.846.438.039.233.530.544.934.935.132.935.430.333.624.031.528.0

us-gaap:NoninterestIncome

us-gaap:NoninterestIncome


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value261922109.873.66414111111148.056168.0916.924116.6583.293
Percentage of NoninterestIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestIncome us-gaap:ConsolidationItems

mbin:CorporateReconcilingItemsAndEliminations


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value-0.942-0.921-0.686-0.739-0.688-0.663-0.514-0.564-0.532-0.336
Percentage of NoninterestIncome-3.6-4.6-3.0-6.8-7.0-18.1-3.5-4.7-4.6-3.0

us-gaap:NoninterestIncome us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value9.1790.6830.9990.883
Percentage of NoninterestIncome35.13.410.124.1

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value5.6262.7762.5852.6991.1410.7530.6010.7790.6840.4860.7570.7760.6780.6251.1520.89
Percentage of NoninterestIncome21.513.911.424.911.620.64.16.55.94.35.19.64.17.716.67.7

us-gaap:OperatingSegments, mbin:MultiFamilyMortgageBanking


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1217209.7598.4182.69113101010146.636157.2235.3889.52
Percentage of NoninterestIncome47.187.291.789.985.373.493.991.391.392.998.182.491.689.377.881.9

us-gaap:NoninterestIncomeOther

us-gaap:NoninterestIncomeOther


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2032000.01814000.02244000.01251000.01192000.0488000.0758000.0453000.0560000.0257000.0357000.0186000.0402000.064000.0258000.0100000.0
Percentage of NoninterestIncomeOther100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OccupancyNet

us-gaap:OccupancyNet


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1383000.01492000.01793000.0994000.0946000.0876000.0726000.0736000.0761000.0565000.0522000.0326000.0398000.0356000.0341000.0331000.0
Percentage of OccupancyNet100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312016-09-30
Value-218000.0468000.0-234000.052000.0486000.0464000.0987000.0173000.097000.0-318000.0-535000.086000.0-586000.0-103000.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent us-gaap:StatementEquityComponents

us-gaap:AccumulatedOtherComprehensiveIncome


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value-218000.0468000.052000.0486000.0464000.0987000.0173000.097000.0-318000.0-535000.0
Percentage of OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax

us-gaap:OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302017-12-312017-09-302016-12-312016-09-30
Value00-86000.001000.032000.000000010000.0
Percentage of OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIForSaleOfSecuritiesTax0.00.0100.00.0100.0100.00.00.00.00.00.00.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-218000.0468000.032000.052000.0484000.0559000.0987000.0173000.097000.0-318000.0-535000.086000.0-67000.0138000.0-586000.0-89000.0
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax

us-gaap:OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-83000.0-152000.034000.07000.0153000.0192000.0279000.058000.054000.0-97000.0-361000.057000.0-46000.096000.0-398000.0-59000.0
Percentage of OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherNoninterestExpense

us-gaap:OtherNoninterestExpense


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1739000.02432000.02547000.02100000.02364000.01370000.02052000.01346000.01463000.01237000.01207000.01031000.0833000.0785000.0747000.01069000.0
Percentage of OtherNoninterestExpense100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForFederalHomeLoanBankAdvances

us-gaap:PaymentsForFederalHomeLoanBankAdvances


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value533420081170351922093952521411422892250.361239120
Percentage of PaymentsForFederalHomeLoanBankAdvances100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForOriginationAndPurchasesOfLoansHeldForSale

us-gaap:PaymentsForOriginationAndPurchasesOfLoansHeldForSale


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value2346211551118911100973473776445719337342409843084847503845085332
Percentage of PaymentsForOriginationAndPurchasesOfLoansHeldForSale100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsForProceedsFromLoansReceivable

us-gaap:PaymentsForProceedsFromLoansReceivable


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value5604592473671601098048218137134107128-69.773-99.359
Percentage of PaymentsForProceedsFromLoansReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt

us-gaap:PaymentsToAcquireAvailableForSaleSecuritiesDebt


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value2031567945
Percentage of PaymentsToAcquireAvailableForSaleSecuritiesDebt100.0100.0100.0100.0

us-gaap:PaymentsToAcquireFederalHomeLoanBankStock

us-gaap:PaymentsToAcquireFederalHomeLoanBankStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value7.068251.791.1591.066110.7230.1030.0120.118
Percentage of PaymentsToAcquireFederalHomeLoanBankStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PaymentsToAcquireLoansHeldForInvestment

us-gaap:PaymentsToAcquireLoansHeldForInvestment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value723225281914263443343231333624
Percentage of PaymentsToAcquireLoansHeldForInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PreferredStockDividendRatePercentage us-gaap:StatementClassOfStock

us-gaap:PreferredStockDividendRatePercentage

mbin:PreferredStock6


None
Period End2020-06-302020-03-312019-12-312019-08-19
Value0.060.0600.06
Percentage of PreferredStockDividendRatePercentage100.0100.00.0100.0

mbin:PreferredStock7


None
Period End2020-06-302020-03-312019-12-312019-09-232019-06-302019-03-282019-03-232019-03-31
Value0.070.0700.070.070.070.070.07
Percentage of PreferredStockDividendRatePercentage116.7116.70.00.00.00.00.00.0

mbin:PreferredStock8


None
Period End2020-06-302020-03-312019-12-312019-06-302019-03-31
Value0.080.0800.080.08
Percentage of PreferredStockDividendRatePercentage133.3133.30.00.00.0

us-gaap:PreferredStockDividendsPerShareDeclared us-gaap:StatementClassOfStock

us-gaap:PreferredStockDividendsPerShareDeclared

mbin:PreferredStock6


None
Period End2020-06-302020-03-312019-09-30
Value60.060.07.1667
Percentage of PreferredStockDividendsPerShareDeclared100.0100.0100.0

mbin:PreferredStock7


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value1.751.750.43750.4375
Percentage of PreferredStockDividendsPerShareDeclared2.92.96.10.0

mbin:PreferredStock8


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-09-302018-06-302018-03-31
Value80.080.020.020.020.020.020.020.0
Percentage of PreferredStockDividendsPerShareDeclared133.3133.3279.10.00.00.00.00.0

us-gaap:ProceedsFromFederalHomeLoanBankAdvances

us-gaap:ProceedsFromFederalHomeLoanBankAdvances


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value559720301291324623485521251272842892250.0239120
Percentage of ProceedsFromFederalHomeLoanBankAdvances100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.00.0100.0100.0

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

us-gaap:ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value28210727621011549161103525721.1420.09825
Percentage of ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromNotesPayable

us-gaap:ProceedsFromNotesPayable


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-30
Value2.310.450.20.9140.84.4049.5825.334
Percentage of ProceedsFromNotesPayable100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell

us-gaap:ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value34000.038000.037000.038000.040000.037000.038000.041000.048000.041000.037000.0-1745000.027000.030000.028000.0
Percentage of ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt

us-gaap:ProceedsFromSaleOfAvailableForSaleSecuritiesDebt


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value0.00.00.03531
Percentage of ProceedsFromSaleOfAvailableForSaleSecuritiesDebt0.00.0100.0100.0

us-gaap:ProceedsFromSaleOfLoansHeldForSale

us-gaap:ProceedsFromSaleOfLoansHeldForSale


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-31
Value2239510866123091043563183729464018897476402041175036488644565525
Percentage of ProceedsFromSaleOfLoansHeldForSale100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProfessionalFees

us-gaap:ProfessionalFees


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value726000.0569000.0826000.0508000.0453000.0539000.0830000.0590000.0677000.0488000.0425000.0561000.0315000.0215000.0355000.0204000.0
Percentage of ProfessionalFees100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForLoanAndLeaseLosses

us-gaap:ProvisionForLoanAndLeaseLosses


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value1745000.02998000.0-5887000.01193000.0105000.0649000.0-7650000.0617000.0998000.01406000.0-1400000.0-592000.0240000.0240000.0-240000.0-240000.0
Percentage of ProvisionForLoanAndLeaseLosses100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForLoanAndLeaseLosses us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value49000.038000.0-194000.014000.052000.034000.0-216000.035000.059000.013000.0-13000.0-36000.0-35000.037000.0-25000.0-21000.0
Percentage of ProvisionForLoanAndLeaseLosses2.81.33.31.249.55.22.85.75.90.90.96.1-14.615.410.48.8

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value494000.0796000.0-1982000.0533000.0311000.0186000.0-1221000.073000.0140000.0223000.0-10000.08000.0100000.0-192000.0141000.0256000.0
Percentage of ProvisionForLoanAndLeaseLosses28.326.633.744.7296.228.716.011.814.015.90.7-1.441.7-80.0-58.8-106.7

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value2184000.0676000.0-855000.0753000.0-1233000.0347000.0-3928000.0240000.0412000.0748000.0-800000.0-276000.0329000.0135000.0-66000.0-159000.0
Percentage of ProvisionForLoanAndLeaseLosses125.222.514.563.1-1174.353.551.338.941.353.257.146.6137.156.227.566.2

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-1188000.01445000.0-2717000.0-174000.01003000.071000.0-1538000.0184000.0252000.0323000.0-341000.0-688000.0-148000.0518000.0153000.0-284000.0
Percentage of ProvisionForLoanAndLeaseLosses-68.148.246.2-14.6955.210.920.129.825.323.024.4116.2-61.7215.8-63.8118.3

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-42000.023000.0-77000.04000.033000.07000.0-43000.0-11000.02000.023000.0-173000.0-14000.0-16000.0-16000.02000.0-14000.0
Percentage of ProvisionForLoanAndLeaseLosses-2.40.81.30.331.41.10.6-1.80.21.612.42.4-6.7-6.7-0.85.8

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value248000.020000.0-62000.063000.0-61000.04000.0-704000.096000.0133000.076000.0-63000.0414000.010000.0-242000.0-445000.0-18000.0
Percentage of ProvisionForLoanAndLeaseLosses14.20.71.15.3-58.10.69.215.613.35.44.5-69.94.2-100.8185.47.5

us-gaap:ProvisionForLoanLossesExpensed

us-gaap:ProvisionForLoanLossesExpensed


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302016-03-31
Value1745000.02998000.01993000.01193000.0105000.0649000.01608000.0617000.0998000.01406000.01400000.0592000.0240000.0240000.0240000.0240000.0240000.0240000.0
Percentage of ProvisionForLoanLossesExpensed100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ProvisionForLoanLossesExpensed us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments

us-gaap:OperatingSegments, mbin:BankingSegment


None
Period End2020-06-302020-03-312019-06-302019-03-31
Value2545000.01818000.0-222000.0516000.0
Percentage of ProvisionForLoanLossesExpensed145.860.6-211.479.5

us-gaap:OperatingSegments, mbin:MortgageWarehousing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-30
Value-800000.01180000.0483000.0415000.0327000.0133000.0187000.0227000.0284000.0674000.0202000.0-155000.0158000.0247000.0-472000.0-61000.0
Percentage of ProvisionForLoanLossesExpensed-45.839.424.234.8311.420.511.636.828.547.914.4-26.265.8102.9-196.7-25.4

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod us-gaap:AwardType, us-gaap:PlanName

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod

us-gaap:RestrictedStock, mbin:RestrictedStockPlan2016


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-31
Value036046.00010127.00007039.00003200.0
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod0.0100.00.00.0100.00.00.00.0100.00.00.00.0100.0

us-gaap:ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod us-gaap:TitleOfIndividual

mbin:NonExecutiveDirector


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value3130.00002275.00001830.00
Percentage of ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod0.00.00.00.00.00.00.00.00.00.0

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensationGross us-gaap:StatementEquityComponents

us-gaap:StockIssuedDuringPeriodSharesShareBasedCompensationGross

us-gaap:CommonStock


None
Period End2020-06-302020-03-312019-06-302019-03-312018-12-312018-06-302018-03-312017-12-31
Value3130.036046.02275.010127.001830.07039.0-4.0
Percentage of StockIssuedDuringPeriodSharesShareBasedCompensationGross100.0100.0100.0100.00.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value203000.0106000.0133000.0184000.0133000.036000.069000.011000.050000.0416000.0
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:StockIssuedDuringPeriodValueShareBasedCompensation us-gaap:StatementEquityComponents

us-gaap:CommonStock


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value203000.0106000.0133000.0184000.0133000.036000.069000.011000.050000.0416000.0
Percentage of StockIssuedDuringPeriodValueShareBasedCompensation100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:DerivativeNotionalAmount1 us-gaap:DerivativeInstrumentRisk

mbin:DerivativeNotionalAmount1

us-gaap:ForwardContracts


None
Period End2020-03-312019-12-312018-12-31
Value1223419
Percentage of DerivativeNotionalAmount1100.0100.0100.0

us-gaap:InterestRateLockCommitments


None
Period End2020-03-312019-12-312018-12-31
Value162178.812
Percentage of DerivativeNotionalAmount1132.252.044.9

us-gaap:InterestRateSwap


None
Period End2020-03-312019-12-31
Value6258
Percentage of DerivativeNotionalAmount150.9169.4

mbin:FederalReserveDiscountWindowAdvancesFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

mbin:FederalReserveDiscountWindowAdvancesFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-30
Value575
Percentage of FederalReserveDiscountWindowAdvancesFairValueDisclosure100.0

mbin:FederalReserveDiscountWindowAdvancesFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-30
Value575
Percentage of FederalReserveDiscountWindowAdvancesFairValueDisclosure100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-30
Value575
Percentage of FederalReserveDiscountWindowAdvancesFairValueDisclosure100.0

mbin:ImpairedLoansFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

mbin:ImpairedLoansFairValueDisclosure

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsNonrecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1262000.01306000.01570000.01600000.01600000.01600000.02639000.0149000.0371000.0758000.02126000.0225000.0
Percentage of ImpairedLoansFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:ImpairedLoansFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument

us-gaap:FairValueInputsLevel3, mbin:CollateralDependentImpairedLoans


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1262000.01306000.01570000.01600000.01600000.01600000.02639000.0
Percentage of ImpairedLoansFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0

mbin:ImpairedLoansFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsNonrecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value1262000.01306000.01570000.01600000.01600000.01600000.02639000.0149000.0371000.0758000.02126000.0225000.0
Percentage of ImpairedLoansFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:ImpairedLoansMeasurementInputMarketabilityDiscountRate us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FinancialInstrument

mbin:ImpairedLoansMeasurementInputMarketabilityDiscountRate

srt:Maximum, us-gaap:FairValueInputsLevel3, mbin:CollateralDependentImpairedLoans


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value0.790.7555.00.59
Percentage of ImpairedLoansMeasurementInputMarketabilityDiscountRate100.0100.0100.0100.0

srt:Minimum, us-gaap:FairValueInputsLevel3, mbin:CollateralDependentImpairedLoans


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value0.450.440.370.17
Percentage of ImpairedLoansMeasurementInputMarketabilityDiscountRate57.058.70.728.8

srt:WeightedAverage, us-gaap:FairValueInputsLevel3, mbin:CollateralDependentImpairedLoans


None
Period End2020-06-30
Value0.46
Percentage of ImpairedLoansMeasurementInputMarketabilityDiscountRate58.2

mbin:InterestPayableFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

mbin:InterestPayableFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.1321011137.6434.934.1326.0644.6553.9962.8172.3641.791
Percentage of InterestPayableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:InterestPayableFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.1321011137.6434.934.1326.0644.6553.9962.8172.3641.791
Percentage of InterestPayableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.1321011137.6434.934.1326.0644.6553.9962.8172.3641.791
Percentage of InterestPayableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:InterestReceivableFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

mbin:InterestReceivableFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1818181817141312109.6278.3267.1965.368
Percentage of InterestReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:InterestReceivableFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1818181817141312109.6278.3267.1965.368
Percentage of InterestReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1818181817141312109.6278.3267.1965.368
Percentage of InterestReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

mbin:OtherAssetsAndReceivables

mbin:OtherAssetsAndReceivables


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value47483029332832252524222331
Percentage of OtherAssetsAndReceivables100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value923000.01200000.0618000.0624000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax us-gaap:FinancialInstrument

mbin:MunicipalSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value513000.0385000.0360000.0336000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax55.632.158.353.8

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value333000.0343000.0213000.0254000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax36.128.634.540.7

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value36000.0423000.024000.08000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax3.935.23.91.3

us-gaap:USTreasuryNotesSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value41000.049000.021000.026000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax4.44.13.44.2

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value25000.01000.039000.01082000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax us-gaap:FinancialInstrument

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value2000.01000.02000.079000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax8.0100.05.17.3

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302019-12-312018-12-31
Value23000.037000.0972000.0
Percentage of AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax92.094.989.8

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value258337289331
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis100.0100.0100.0100.0

us-gaap:AvailableForSaleDebtSecuritiesAmortizedCostBasis us-gaap:FinancialInstrument

mbin:MunicipalSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value5.5555.5665.57721
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis2.11.61.96.3

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value23243460
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis9.07.111.918.3

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value225306244237
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis87.390.684.671.8

us-gaap:USTreasuryNotesSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value3.9911.9944.74411
Percentage of AvailableForSaleDebtSecuritiesAmortizedCostBasis1.50.61.63.6

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3.4962023169414917916620618416419868
Percentage of AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3.5142023169414917816520518416419868
Percentage of AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-06-302018-03-312017-12-31
Value4.7695.2985.3097.9237.947.957116.26.26.2
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-06-302018-03-312017-12-31
Value5.2215.6695.6598.58.3868.252126.26.26.2
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value227287226246118987279149198212206232
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value227288226246119987278148197211206231
Percentage of AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value235314255272224258270244360387382404299
Percentage of AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value235313255272223258270245362389384405300
Percentage of AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value23243435363860
Percentage of AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue us-gaap:FinancialInstrument

us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value23243435363860
Percentage of AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue100.0100.0100.0100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtSecurities

us-gaap:AvailableForSaleSecuritiesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value259339290331
Percentage of AvailableForSaleSecuritiesDebtSecurities100.0100.0100.0100.0

us-gaap:AvailableForSaleSecuritiesDebtSecurities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueInputsLevel1, us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasurySecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value4.0322.0434.76511
Percentage of AvailableForSaleSecuritiesDebtSecurities1.60.61.63.6

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value23243460
Percentage of AvailableForSaleSecuritiesDebtSecurities9.17.211.918.4

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value225306244236
Percentage of AvailableForSaleSecuritiesDebtSecurities87.090.484.471.6

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring, us-gaap:USStatesAndPoliticalSubdivisions


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value6.0685.9515.93721
Percentage of AvailableForSaleSecuritiesDebtSecurities2.31.82.06.4

us-gaap:AvailableForSaleSecuritiesDebtSecurities us-gaap:FairValueByMeasurementFrequency, us-gaap:FinancialInstrument

us-gaap:FairValueMeasurementsRecurring, us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value23243460
Percentage of AvailableForSaleSecuritiesDebtSecurities9.17.211.918.4

us-gaap:FairValueMeasurementsRecurring, us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value225306244236
Percentage of AvailableForSaleSecuritiesDebtSecurities87.090.484.471.6

us-gaap:FairValueMeasurementsRecurring, us-gaap:USStatesAndPoliticalSubdivisions


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value6.0685.9515.93721
Percentage of AvailableForSaleSecuritiesDebtSecurities2.31.82.06.4

us-gaap:FairValueMeasurementsRecurring, us-gaap:USTreasurySecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value4.0322.0434.76511
Percentage of AvailableForSaleSecuritiesDebtSecurities1.60.61.63.6

us-gaap:AvailableForSaleSecuritiesDebtSecurities us-gaap:FinancialInstrument

mbin:MunicipalSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value6.0685.9515.93721
Percentage of AvailableForSaleSecuritiesDebtSecurities2.31.82.06.4

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value23243460
Percentage of AvailableForSaleSecuritiesDebtSecurities9.17.211.918.4

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value225306244236
Percentage of AvailableForSaleSecuritiesDebtSecurities87.090.484.471.6

us-gaap:USTreasuryNotesSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value4.0322.0434.76511
Percentage of AvailableForSaleSecuritiesDebtSecurities1.60.61.63.6

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:CashAndCashEquivalentsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value403568506364460313336410352287359566445
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndCashEquivalentsFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value403568506364460313336410352287359566445
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value403568506364460313336410352287359566445
Percentage of CashAndCashEquivalentsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashAndDueFromBanks

us-gaap:CashAndDueFromBanks


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value138.1681315151925201821181410
Percentage of CashAndDueFromBanks100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:CashCollateralForBorrowedSecurities

us-gaap:CashCollateralForBorrowedSecurities


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value3900000.03100000.0590000.00
Percentage of CashCollateralForBorrowedSecurities100.0100.0100.00.0

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value901.1139547
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months us-gaap:FinancialInstrument

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value0.6751.1130.80915
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months0.7100.00.832.5

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302019-12-312018-12-31
Value899428
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months99.399.259.1

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value25000.01000.039000.0202000.0
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss us-gaap:FinancialInstrument

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value2000.01000.02000.079000.0
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss8.0100.05.139.1

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302019-12-312018-12-31
Value23000.037000.097000.0
Percentage of DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss92.094.948.0

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value901.11395240
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPosition us-gaap:FinancialInstrument

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value0.6751.1130.80915
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition0.7100.00.86.5

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302019-12-312018-12-31
Value8994219
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPosition99.399.191.4

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value25000.01000.039000.01082000.0
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss100.0100.0100.0100.0

us-gaap:DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss us-gaap:FinancialInstrument

us-gaap:MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprises


None
Period End2020-06-302020-03-312019-12-312018-12-31
Value2000.01000.02000.079000.0
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss8.0100.05.17.3

us-gaap:USGovernmentAgenciesDebtSecurities


None
Period End2020-06-302019-12-312018-12-31
Value23000.037000.0972000.0
Percentage of DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss92.094.989.8

us-gaap:Deposits

us-gaap:Deposits


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6908672254785499465531213231330231763062294329012428
Percentage of Deposits100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:DepositsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:DepositsFairValueDisclosure

us-gaap:FairValueInputsLevel1, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value5263396733033248291924382550271224802457253425112262
Percentage of DepositsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value16502762217422511737682679589695604408389166
Percentage of DepositsFairValueDisclosure31.469.665.869.359.528.026.721.728.024.616.115.57.3

us-gaap:DepositsFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6908672254785499465531213231330231763062294329012428
Percentage of DepositsFairValueDisclosure131.3169.5165.8169.3159.5128.0126.7121.8128.1124.6116.1115.5107.3

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6913673054785500465631203230330131753062294329012428
Percentage of DepositsFairValueDisclosure131.4169.6165.8169.3159.5128.0126.7121.7128.0124.6116.1115.5107.3

us-gaap:DerivativeAssetMeasurementInput us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType

us-gaap:DerivativeAssetMeasurementInput

srt:Maximum, us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputMaturity


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value0.990.9999.00.990.991.0
Percentage of DerivativeAssetMeasurementInput100.0100.0100.0100.0100.0100.0

srt:Minimum, us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputMaturity


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value0.530.560.730.730.730.95
Percentage of DerivativeAssetMeasurementInput53.556.60.773.773.795.0

srt:WeightedAverage, us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputMaturity


None
Period End2020-06-30
Value0.77
Percentage of DerivativeAssetMeasurementInput77.8

us-gaap:DerivativeAssets us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass

us-gaap:DerivativeAssets

us-gaap:ForwardContracts, us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value16000.096000.014000.01000.0
Percentage of DerivativeAssets100.0100.0100.0100.0

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5742000.02079000.0186000.0296000.0147000.071000.070000.0
Percentage of DerivativeAssets35887.52165.60.02114.314700.00.00.0

us-gaap:InterestRateSwap, us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeAssets24050.03347.90.0342.9

us-gaap:DerivativeAssets us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5742000.02079000.0186000.0296000.0147000.071000.070000.0
Percentage of DerivativeAssets35887.52165.60.02114.314700.00.00.0

us-gaap:DerivativeAssets us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:ForwardContracts, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value16000.096000.014000.01000.0
Percentage of DerivativeAssets100.0100.0100.0100.0

us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5742000.02079000.0186000.0296000.0147000.071000.070000.0
Percentage of DerivativeAssets35887.52165.60.02114.314700.00.00.0

us-gaap:InterestRateSwap, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeAssets24050.03347.90.0342.9

us-gaap:DerivativeAssets us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency

us-gaap:ForwardContracts, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-09-302019-06-30
Value16000.096000.014000.01000.0
Percentage of DerivativeAssets100.0100.0100.0100.0

us-gaap:InterestRateLockCommitments, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value5742000.02079000.0186000.0296000.0147000.071000.070000.0
Percentage of DerivativeAssets35887.52165.60.02114.314700.00.00.0

us-gaap:InterestRateSwap, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeAssets24050.03347.90.0342.9

us-gaap:DerivativeAssets us-gaap:FairValueByAssetClass

us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5758000.02175000.0186000.0310000.0148000.071000.070000.074000.0170000.0128000.0
Percentage of DerivativeAssets35987.52265.60.02214.314800.00.00.00.00.00.0

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel

us-gaap:DerivativeLiabilities

us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3


None
Period End2020-03-312019-09-302019-06-302019-03-31
Value80000.08000.03000.01000.0
Percentage of DerivativeLiabilities100.0100.0100.0100.0

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:ForwardContracts, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1249000.01273000.027000.016000.019000.018000.09000.0
Percentage of DerivativeLiabilities0.01591.20.0200.0633.31800.00.0

us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-03-312019-09-302019-06-302019-03-31
Value80000.08000.03000.01000.0
Percentage of DerivativeLiabilities100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeLiabilities0.04017.50.0600.0

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass

us-gaap:ForwardContracts, us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1249000.01273000.027000.016000.019000.018000.09000.0
Percentage of DerivativeLiabilities0.01591.20.0200.0633.31800.00.0

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-03-312019-09-302019-06-302019-03-31
Value80000.08000.03000.01000.0
Percentage of DerivativeLiabilities100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeLiabilities0.04017.50.0600.0

us-gaap:DerivativeLiabilities us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByMeasurementFrequency

us-gaap:ForwardContracts, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value1249000.01273000.027000.016000.019000.018000.09000.0
Percentage of DerivativeLiabilities0.01591.20.0200.0633.31800.00.0

us-gaap:InterestRateLockCommitments, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-03-312019-09-302019-06-302019-03-31
Value80000.08000.03000.01000.0
Percentage of DerivativeLiabilities100.0100.0100.0100.0

us-gaap:InterestRateSwap, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value3848000.03214000.0511000.048000.0
Percentage of DerivativeLiabilities0.04017.50.0600.0

us-gaap:DerivativeLiabilities us-gaap:FairValueByLiabilityClass

us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value1249000.01353000.027000.024000.022000.019000.09000.01000.077000.034000.0
Percentage of DerivativeLiabilities0.01691.20.0300.0733.31900.00.00.00.00.0

us-gaap:DerivativeLiabilityMeasurementInput us-gaap:Range, us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:MeasurementInputType

us-gaap:DerivativeLiabilityMeasurementInput

srt:Minimum, us-gaap:InterestRateLockCommitments, us-gaap:FairValueInputsLevel3, us-gaap:MeasurementInputMaturity


None
Period End2020-03-312019-09-302019-06-30
Value0.560.730.73
Percentage of DerivativeLiabilityMeasurementInput100.0100.0100.0

us-gaap:DerivativeNotionalAmount us-gaap:DerivativeInstrumentRisk

us-gaap:DerivativeNotionalAmount

us-gaap:ForwardContracts


None
Period End2020-06-302019-12-31
Value24134
Percentage of DerivativeNotionalAmount100.0100.0

us-gaap:InterestRateLockCommitments


None
Period End2020-06-302019-12-31
Value35317
Percentage of DerivativeNotionalAmount146.352.0

us-gaap:InterestRateSwap


None
Period End2020-06-302019-12-31
Value8258
Percentage of DerivativeNotionalAmount34.4169.4

us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value14121212111310393430303030
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value14121212111310393430303030
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value14121212111310393430303030
Percentage of FairValueLiabilitiesMeasuredOnRecurringBasisSubordinatedDebtObligations100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByAssetClass

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsAssets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value5.7422.0790.1860.2960.1470.0710.070.0680.170.116
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue us-gaap:FairValueByAssetClass

us-gaap:Assets


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312015-12-312014-12-31
Value7269747174767771706766625754535552
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue1269.43365.939993.024320.650714.3107393.0111205.7105132.441226.557989.70.00.00.00.00.00.00.0

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue us-gaap:DerivativeInstrumentRisk, us-gaap:FairValueByLiabilityClass

us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue

us-gaap:InterestRateLockCommitments, us-gaap:DerivativeFinancialInstrumentsLiabilities


None
Period End2020-03-312019-09-302019-06-302019-03-312018-06-302018-03-31
Value80000.08000.03000.01000.07000.02000.0
Percentage of FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue100.0100.0100.0100.0100.0100.0

us-gaap:FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6651000.06685000.06723000.06760000.06798000.06838000.06875000.06913000.06954000.07003000.07043000.07080000.05392000.0
Percentage of FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6651000.06685000.06723000.06760000.06798000.06838000.06875000.06913000.06954000.07003000.07043000.07080000.05392000.0
Percentage of FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6651000.06685000.06723000.06760000.06798000.06838000.06875000.06913000.06954000.07003000.07043000.07080000.05392000.0
Percentage of FederalFundsSoldAndSecuritiesBorrowedOrPurchasedUnderAgreementsToResellFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FederalHomeLoanBankBorrowingsFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:FederalHomeLoanBankBorrowingsFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1130431162147172921512.7231301441.621.6452.031
Percentage of FederalHomeLoanBankBorrowingsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FederalHomeLoanBankBorrowingsFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1171431162147172921512.7451301441.6121.6242.006
Percentage of FederalHomeLoanBankBorrowingsFairValueDisclosure103.6100.199.999.999.6100.0100.0100.8100.0100.099.598.798.8

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1130431162147172921512.7231301441.621.6452.031
Percentage of FederalHomeLoanBankBorrowingsFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FederalHomeLoanBankStock

us-gaap:FederalHomeLoanBankStock


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value5346201818187.9747.6087.7237.7117.5397.5397.539
Percentage of FederalHomeLoanBankStock100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment

us-gaap:FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1917151311121210109.0737.9497.4416.209
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.610.5610.5230.5020.4880.4460.4090.4070.3720.3160.3040.2910.258
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment3.13.23.43.84.13.53.43.83.73.53.83.94.2

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3.2032.7091.9131.9911.341.0290.8430.5440.4710.3310.2830.2730.373
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment16.515.312.615.211.38.27.05.14.73.63.63.76.0

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9.8787.6947.0185.8975.1446.3776.034.9024.6624.253.5022.7021.962
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment50.943.546.345.043.450.650.045.846.446.844.136.331.6

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3.2834.4953.5232.5682.7712.6222.6512.8322.6032.3912.1622.5331.374
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment16.925.423.219.623.420.822.026.525.926.427.234.022.1

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.1520.1890.1650.1760.180.1470.140.1250.1270.1210.1110.1180.102
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment0.81.11.11.31.51.21.21.21.31.31.41.61.6

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.2942.0332.0191.9781.9291.991.9861.8921.8121.6641.5871.5242.14
Percentage of FinancingReceivableAllowanceForCreditLossesCollectivelyEvaluatedForImpairment11.811.513.315.116.315.816.517.718.018.320.020.534.5

us-gaap:FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1

us-gaap:FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1077000.01202000.0681000.0593000.0752000.0745000.0645000.0541000.0541000.0632000.0362000.016000.041000.0
Percentage of FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1 us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1060000.01167000.0650000.0544000.0500000.0500000.0400000.0200000.0200000.0294000.0200000.0
Percentage of FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment198.497.195.491.766.567.162.037.037.046.555.2

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302018-09-302018-06-302018-03-312017-12-31
Value1000.06000.08000.08000.0146000.0146000.0146000.0146000.0
Percentage of FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment10.10.51.21.327.027.023.140.3

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302016-12-31
Value16000.029000.023000.014000.030000.0
Percentage of FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment11.52.43.42.473.2

us-gaap:FinancingReceivableCollectivelyEvaluatedForImpairment

us-gaap:FinancingReceivableCollectivelyEvaluatedForImpairment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value413935063015274123462168204619071824156313671205936
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableCollectivelyEvaluatedForImpairment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value96908585838078696863515146
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment2.32.62.83.13.63.73.93.73.84.13.84.35.0

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value12871083764796535411336405397244224233275
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment31.130.925.429.022.819.016.521.321.815.716.519.429.4

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value18481435134711451001965914738703645529393261
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment44.740.944.741.842.744.544.738.738.541.338.732.627.9

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value423459389289307288290283265242222207108
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment10.213.112.910.613.113.314.214.814.515.516.317.211.6

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141818192017171111119.274129.392
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment0.40.50.60.70.90.80.80.60.60.70.71.01.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value468419410405397404409398379356329307235
Percentage of FinancingReceivableCollectivelyEvaluatedForImpairment11.312.013.614.816.918.720.020.920.822.824.125.525.1

us-gaap:FinancingReceivableIndividuallyEvaluatedForImpairment

us-gaap:FinancingReceivableIndividuallyEvaluatedForImpairment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141412141313119.2679.3519.3057.3363.4715.568
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableIndividuallyEvaluatedForImpairment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.2382.0430.2140.3020.3470.370.370.6360.6350.2820.2820.203
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment15.914.51.52.22.63.34.06.86.83.88.13.6

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.230.2330.2370.5660.5720.5750.5790.8040.933
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment1.61.91.74.14.35.16.28.610.0

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9.0199.4259.1528.4377.8848.1868.5766.9746.5396.7476.1792.9825.022
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment64.066.773.159.957.061.076.775.369.972.584.285.990.2

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.0190.0160.0230.0250.0530.050.0580.1870.1960.1460.146
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment0.10.10.20.20.40.40.52.02.11.62.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.8272.413.1095.1615.0264.2551.6061.0481.0660.7280.7290.2070.343
Percentage of FinancingReceivableIndividuallyEvaluatedForImpairment20.017.124.836.736.331.714.411.311.47.89.96.06.2

us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing

us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value4019000.03881000.02569000.03973000.02071000.0779000.0507000.0462000.0653000.01091000.0592000.01969000.0685000.0
Percentage of FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value2221000.01908000.0231000.0386000.0729000.0317000.0307000.0307000.0126000.0117000.0117000.0107000.0
Percentage of FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing55.349.29.09.735.240.760.666.519.310.719.815.6

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-312018-06-302018-03-312017-09-30
Value1622000.0396000.0486000.0805000.0121000.0117000.043000.0136000.01969000.0
Percentage of FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing40.410.218.920.35.823.16.612.5100.0

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-03-31
Value1000.026000.01000.010000.06000.08000.09000.08000.0
Percentage of FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing0.00.70.00.30.31.01.80.7

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312016-12-31
Value175000.01551000.01851000.02772000.01215000.0454000.074000.0155000.0484000.0714000.0475000.0578000.0
Percentage of FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing4.440.072.169.858.758.314.633.574.165.480.284.4

us-gaap:FinancingReceivableRecordedInvestmentCurrent

us-gaap:FinancingReceivableRecordedInvestmentCurrent


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value414435113015274623542175205419141826156713701198937
Percentage of FinancingReceivableRecordedInvestmentCurrent100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableRecordedInvestmentCurrent us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value96908284828078696864515146
Percentage of FinancingReceivableRecordedInvestmentCurrent2.32.62.83.13.53.73.83.63.74.13.84.35.0

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value12871083765796536411337405397244224233275
Percentage of FinancingReceivableRecordedInvestmentCurrent31.130.925.429.022.818.916.421.221.815.616.419.529.3

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value18481435134711451001965914738700645529386261
Percentage of FinancingReceivableRecordedInvestmentCurrent44.640.944.741.742.544.444.538.638.341.238.632.227.8

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value427465394293313295298289269246225207110
Percentage of FinancingReceivableRecordedInvestmentCurrent10.313.313.110.713.313.614.515.114.715.816.517.311.8

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141718192017171111119.274129.392
Percentage of FinancingReceivableRecordedInvestmentCurrent0.30.50.60.70.90.80.80.60.60.70.71.01.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value470418407406399404409398379355329307234
Percentage of FinancingReceivableRecordedInvestmentCurrent11.411.913.514.817.018.619.920.820.822.724.125.625.0

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2653000.02676000.02109000.02160000.01731000.01774000.01904000.01443000.03669000.03808000.02548000.0906000.01202000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableRecordedInvestmentNonaccrualStatus us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value195000.0214000.0214000.0259000.0282000.0282000.0282000.0282000.0282000.0282000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus7.49.912.414.614.819.57.77.411.131.1

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value230000.0233000.0237000.0566000.0572000.0575000.0579000.0804000.0933000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus8.611.011.032.732.230.240.121.924.5

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1809000.01766000.01118000.0858000.0257000.0228000.0136000.0165000.02146000.02169000.02060000.0417000.0899000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus68.266.053.039.714.812.97.111.458.557.080.846.074.8

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value19000.016000.018000.018000.019000.013000.018000.0154000.0162000.0166000.0146000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus0.70.60.90.81.10.70.910.74.44.45.7

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value630000.0664000.0740000.0833000.0675000.0702000.0893000.0263000.0275000.0258000.060000.0207000.0303000.0
Percentage of FinancingReceivableRecordedInvestmentNonaccrualStatus23.724.835.138.639.039.646.918.27.56.82.422.825.2

us-gaap:FinancingReceivableRecordedInvestmentPastDue

us-gaap:FinancingReceivableRecordedInvestmentPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value8.8769.516129.2445.6426.3263.2173.0358.2155.8744.253104.175
Percentage of FinancingReceivableRecordedInvestmentPastDue100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:FinancingReceivableRecordedInvestmentPastDue us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.7262.4892.2420.761.2480.630.6790.6590.7960.5380.4580.3810.294
Percentage of FinancingReceivableRecordedInvestmentPastDue30.726.217.88.222.110.021.121.79.79.210.83.67.0

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value4.643.0764.2914.2181.5460.6720.550.2742.4762.442.9212.5262.96
Percentage of FinancingReceivableRecordedInvestmentPastDue52.332.334.045.627.410.617.19.030.141.568.723.870.9

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.6470.6880.10.0740.0580.0340.0820.2280.2020.1890.146
Percentage of FinancingReceivableRecordedInvestmentPastDue7.37.20.80.81.00.52.57.52.53.23.4

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.8633.2635.9754.1922.4664.6661.5821.551.0191.6580.7280.3030.921
Percentage of FinancingReceivableRecordedInvestmentPastDue9.734.347.445.343.773.849.251.112.428.217.12.922.1

us-gaap:FinancingReceivableRecordedInvestmentPastDue us-gaap:FinancingReceivablePortfolioSegment, us-gaap:FinancingReceivablesPeriodPastDue

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:FinancingReceivables30To59DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.2120.4292.0470.1590.2640.0530.0910.0710.3890.1390.0590.0250.101
Percentage of FinancingReceivableRecordedInvestmentPastDue2.44.516.21.74.70.82.82.34.72.41.40.22.4

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:FinancingReceivables60To89DaysPastDue


None
Period End2020-06-302020-03-312019-06-302017-09-302016-12-31
Value0.0970.1520.0410.0740.086
Percentage of FinancingReceivableRecordedInvestmentPastDue1.11.60.70.72.1

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.4171.9080.1950.6010.9430.5770.5880.5880.4070.3990.3990.2820.107
Percentage of FinancingReceivableRecordedInvestmentPastDue27.220.11.56.516.79.118.319.45.06.89.42.72.6

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:FinancingReceivables30To59DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302016-12-31
Value1.5220.2742.2932.4430.480.1910.2450.1090.1480.120.0180.043
Percentage of FinancingReceivableRecordedInvestmentPastDue17.12.918.226.48.53.07.63.61.82.00.21.0

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:FinancingReceivables60To89DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.3680.6220.3350.1110.7410.3060.0520.140.0150.860.1222.018
Percentage of FinancingReceivableRecordedInvestmentPastDue4.16.52.71.213.14.81.61.70.320.21.148.3

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.752.181.6631.6640.3250.1750.2530.1652.1882.3052.0612.3860.899
Percentage of FinancingReceivableRecordedInvestmentPastDue31.022.913.218.05.82.87.95.426.639.248.522.421.5

us-gaap:ConsumerPortfolioSegment, us-gaap:FinancingReceivables30To59DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.0140.610.050.0250.0060.0130.0020.0570.010.011
Percentage of FinancingReceivableRecordedInvestmentPastDue0.26.40.40.30.10.20.11.90.10.2

us-gaap:ConsumerPortfolioSegment, us-gaap:FinancingReceivables60To89DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-312018-09-302018-06-302018-03-31
Value0.0110.0360.0310.0220.0260.0520.0180.0310.006
Percentage of FinancingReceivableRecordedInvestmentPastDue0.10.40.20.20.51.60.60.40.1

us-gaap:ConsumerPortfolioSegment, us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.6220.0420.0190.0270.0260.0210.0280.1530.1610.1720.146
Percentage of FinancingReceivableRecordedInvestmentPastDue7.00.40.20.30.50.30.95.02.02.93.4

us-gaap:ResidentialPortfolioSegment, us-gaap:FinancingReceivables30To59DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302016-12-31
Value0.1651.0023.0890.4380.6143.4310.5791.1110.2180.5750.0560.04
Percentage of FinancingReceivableRecordedInvestmentPastDue1.910.524.54.710.954.218.036.62.79.80.51.0

us-gaap:ResidentialPortfolioSegment, us-gaap:FinancingReceivables60To89DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value0.1380.2890.5620.5480.2460.2370.1780.080.1150.1230.1940.04
Percentage of FinancingReceivableRecordedInvestmentPastDue1.63.04.55.94.43.75.52.61.42.14.60.4

us-gaap:ResidentialPortfolioSegment, us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.561.9722.3243.2061.6060.9980.8250.3590.6860.960.5340.2070.881
Percentage of FinancingReceivableRecordedInvestmentPastDue6.320.718.434.728.515.825.611.88.416.312.61.921.1

us-gaap:FinancingReceivableRecordedInvestmentPastDue us-gaap:FinancingReceivablesPeriodPastDue

us-gaap:FinancingReceivables30To59DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1.9132.3157.4793.0651.3643.6880.9171.3483.9410.8450.0596.2290.184
Percentage of FinancingReceivableRecordedInvestmentPastDue21.624.359.333.224.258.328.544.448.014.41.458.64.4

us-gaap:FinancingReceivables60To89DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.6141.0990.9280.6811.0540.5430.2820.0980.2861.0771.0541.5262.104
Percentage of FinancingReceivableRecordedInvestmentPastDue6.911.57.47.418.78.68.83.23.518.324.814.450.4

us-gaap:FinancingReceivablesEqualToGreaterThan90DaysPastDue


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.3496.1024.2015.4983.2242.0952.0181.5893.9883.9523.142.8751.887
Percentage of FinancingReceivableRecordedInvestmentPastDue71.564.133.359.557.133.162.752.448.567.373.827.045.2

us-gaap:ImpairedFinancingReceivableRecordedInvestment

us-gaap:ImpairedFinancingReceivableRecordedInvestment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141412141313119.2679.3519.3057.3363.4715.568
Percentage of ImpairedFinancingReceivableRecordedInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableRecordedInvestment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.2382.0430.2140.3020.3470.370.370.6360.6350.2820.2820.203
Percentage of ImpairedFinancingReceivableRecordedInvestment15.914.51.52.22.63.34.06.86.83.88.13.6

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.230.2330.2370.5660.5720.5750.5790.8040.933
Percentage of ImpairedFinancingReceivableRecordedInvestment1.61.91.74.14.35.16.28.610.0

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9.0199.4259.1528.4377.8848.1868.5766.9746.5396.7476.1792.9825.022
Percentage of ImpairedFinancingReceivableRecordedInvestment64.066.773.159.957.061.076.775.369.972.584.285.990.2

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.0190.0160.0230.0250.0530.050.0580.1870.1960.1460.146
Percentage of ImpairedFinancingReceivableRecordedInvestment0.10.10.20.20.40.40.52.02.11.62.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.8272.413.1095.1615.0264.2551.6061.0481.0660.7280.7290.2070.343
Percentage of ImpairedFinancingReceivableRecordedInvestment20.017.124.836.736.331.714.411.311.47.89.96.06.2

us-gaap:ImpairedFinancingReceivableRelatedAllowance

us-gaap:ImpairedFinancingReceivableRelatedAllowance


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1077000.01202000.0681000.0593000.0752000.0745000.0645000.0541000.0541000.0632000.0362000.016000.041000.0
Percentage of ImpairedFinancingReceivableRelatedAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableRelatedAllowance us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value1060000.01167000.0650000.0544000.0500000.0500000.0400000.0200000.0200000.0294000.0200000.0
Percentage of ImpairedFinancingReceivableRelatedAllowance98.497.195.491.766.567.162.037.037.046.555.2

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302018-09-302018-06-302018-03-312017-12-31
Value1000.06000.08000.08000.0146000.0146000.0146000.0146000.0
Percentage of ImpairedFinancingReceivableRelatedAllowance0.10.51.21.327.027.023.140.3

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302016-12-31
Value16000.029000.023000.014000.030000.0
Percentage of ImpairedFinancingReceivableRelatedAllowance1.52.43.42.473.2

us-gaap:ImpairedFinancingReceivableUnpaidPrincipalBalance

us-gaap:ImpairedFinancingReceivableUnpaidPrincipalBalance


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141412141313119.2679.3519.3057.3363.4715.568
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableUnpaidPrincipalBalance us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.2382.0430.2140.3020.3470.370.370.6360.6350.2820.2820.203
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance15.914.51.52.22.63.34.06.86.83.88.13.6

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.230.2330.2370.5660.5720.5750.5790.8040.933
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance1.61.91.74.14.35.16.28.610.0

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9.0199.4259.1528.4377.8848.1868.5766.9746.5396.7476.1792.9825.022
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance64.066.773.159.957.061.076.775.369.972.584.285.990.2

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.0190.0160.0230.0250.0530.050.0580.1870.1960.1460.146
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance0.10.10.20.20.40.40.52.02.11.62.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.8272.413.1095.1615.0264.2551.6061.0481.0660.7280.7290.2070.343
Percentage of ImpairedFinancingReceivableUnpaidPrincipalBalance20.017.124.836.736.331.714.411.311.47.89.96.06.2

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value11119.8061111107.6396.5156.2945.6984.8483.1895.302
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2.2382.0430.0880.0880.0880.0880.3540.353
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment18.917.80.80.81.21.45.66.2

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.230.2330.2370.2420.2480.2510.2550.258
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment2.02.42.12.22.43.33.94.1

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.8347.0286.6626.0195.6055.9075.6364.9744.4564.6174.1192.9825.022
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment57.761.267.953.350.956.073.876.370.881.085.093.594.7

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.0070.0070.0120.0140.0530.050.0580.0410.05
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment0.10.10.10.10.50.50.80.60.8

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.7552.1792.8995.0165.0264.2551.6061.0481.0660.7280.7290.2070.28
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment23.319.029.644.445.640.321.016.116.912.815.06.55.3

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value11119.8061111107.6396.5156.2945.6984.8483.1895.302
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value2.2382.0430.0880.0880.0880.0880.3540.353
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance18.917.80.80.81.21.45.66.2

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.230.2330.2370.2420.2480.2510.2550.258
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance2.02.42.12.22.43.33.94.1

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6.8347.0286.6626.0195.6055.9075.6364.9744.4564.6174.1192.9825.022
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance57.761.267.953.350.956.073.876.370.881.085.093.594.7

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-30
Value0.0070.0070.0120.0140.0530.050.0580.0410.05
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance0.10.10.10.10.50.50.80.60.8

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.7552.1792.8995.0165.0264.2551.6061.0481.0660.7280.7290.2070.28
Percentage of ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance23.319.029.644.445.640.321.016.116.912.815.06.55.3

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2269000.02637000.02711000.02788000.02817000.02862000.03546000.02752000.03057000.03607000.02488000.0282000.0266000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2185000.02397000.02490000.02418000.02279000.02279000.02940000.02000000.02083000.02130000.02060000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment96.390.991.886.780.979.682.972.768.159.182.8

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302018-09-302018-06-302018-03-312017-12-31
Value12000.09000.011000.011000.0146000.0146000.0146000.0146000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment0.50.30.40.45.34.84.05.9

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302016-12-31
Value72000.0231000.0210000.0145000.063000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment3.28.87.75.223.7

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2269000.02637000.02711000.02788000.02817000.02862000.03546000.02752000.03057000.03607000.02488000.0282000.0266000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance us-gaap:FinancingReceivablePortfolioSegment

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value2185000.02397000.02490000.02418000.02279000.02279000.02940000.02000000.02083000.02130000.02060000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance96.390.991.886.780.979.682.972.768.159.182.8

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302018-09-302018-06-302018-03-312017-12-31
Value12000.09000.011000.011000.0146000.0146000.0146000.0146000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance0.50.30.40.45.34.84.05.9

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302016-12-31
Value72000.0231000.0210000.0145000.063000.0
Percentage of ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance3.28.87.75.223.7

us-gaap:InterestBearingDepositLiabilities

us-gaap:InterestBearingDepositLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6307639452065300446329923048296525902409232221801861
Percentage of InterestBearingDepositLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestBearingDepositsInBanks

us-gaap:InterestBearingDepositsInBanks


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value389559492349445293310390334266340551435
Percentage of InterestBearingDepositsInBanks100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InterestReceivable

us-gaap:InterestReceivable


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1818181817141312109.6278.3267.1965.368
Percentage of InterestReceivable100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentInFederalHomeLoanBankStockFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:InvestmentInFederalHomeLoanBankStockFairValueDisclosure

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value5346201818187.9747.6087.7237.7117.5397.5397.539
Percentage of InvestmentInFederalHomeLoanBankStockFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:InvestmentInFederalHomeLoanBankStockFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value5346201818187.9747.6087.7237.7117.5397.5397.539
Percentage of InvestmentInFederalHomeLoanBankStockFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value5346201818187.9747.6087.7237.7117.5397.5397.539
Percentage of InvestmentInFederalHomeLoanBankStockFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansAndLeasesReceivableAllowance

us-gaap:LoansAndLeasesReceivableAllowance


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value2018151312131211109.7058.3117.4576.8656.556.256.015.9025.4224.458
Percentage of LoansAndLeasesReceivableAllowance100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansAndLeasesReceivableAllowance us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value0.610.5610.5230.5290.5150.4660.4290.4270.3920.3330.320.3070.2710.3060.2690.2440.2230.2220.275
Percentage of LoansAndLeasesReceivableAllowance3.03.03.33.94.13.53.43.83.73.43.94.13.94.74.34.13.84.16.2

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value3.2032.7091.9131.9911.5651.2541.0680.7190.6460.5060.2830.2730.2810.1810.3730.5140.770.7040.475
Percentage of LoansAndLeasesReceivableAllowance15.614.312.114.512.49.48.46.46.15.23.43.74.12.86.08.613.013.010.7

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value9.8787.6947.0185.8975.1446.3776.034.9024.6624.253.5022.7022.4262.0971.9621.8961.7371.3080.689
Percentage of LoansAndLeasesReceivableAllowance48.240.744.343.040.847.747.543.644.043.842.136.235.332.031.431.529.424.115.5

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value4.3435.6624.1733.1123.2713.1223.0513.0322.8032.6852.3622.5331.8451.9181.3741.5271.2430.9081.163
Percentage of LoansAndLeasesReceivableAllowance21.230.026.322.726.023.424.027.026.527.728.434.026.929.322.025.421.116.726.1

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value0.1530.1950.1730.1840.180.1470.140.2710.2730.2670.2570.1180.1040.120.1020.1040.090.0680.05
Percentage of LoansAndLeasesReceivableAllowance0.71.01.11.31.41.11.12.42.62.83.11.61.51.81.61.71.51.31.1

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302017-06-302017-03-312016-12-312016-09-302016-06-302015-12-312014-12-31
Value2.312.0622.0421.9921.9291.991.9861.8921.8121.6641.5871.5241.9381.9282.171.7251.8392.2121.806
Percentage of LoansAndLeasesReceivableAllowance11.310.912.914.515.314.915.616.817.117.119.120.428.229.434.728.731.240.840.5

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value415335203028275523602181205819171834157313741209941
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome us-gaap:FinancingReceivablePortfolioSegment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value99928585848179706964515146
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome2.42.62.83.13.63.73.93.73.84.13.84.35.0

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value12871083765796536412337406397245224233275
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome31.030.825.328.922.718.916.421.221.715.616.419.329.2

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value18481435134711451001965914738703645529393261
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome44.540.844.541.642.444.244.438.538.341.038.532.627.7

us-gaap:CommercialRealEstatePortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value432468398297315296299290271249228210113
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome10.413.313.210.813.413.614.515.114.815.916.617.412.1

us-gaap:ConsumerPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141818192017171112119.42129.392
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.40.50.60.70.90.80.80.60.70.70.71.01.0

us-gaap:ResidentialPortfolioSegment


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value471421413410402409410399380356330307235
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome11.412.013.714.917.018.820.020.920.722.724.025.425.0

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value95888380817775666562515146
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome2.32.52.72.93.43.63.73.53.64.03.74.24.9

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value1.6512.0062.1145.1162.5672.7913.0963.3172.6592.0990.3230.351
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.00.10.10.20.10.10.20.20.10.10.00.0

mbin:AgriculturalProductionAndRealEstatePortfolioSegment, us-gaap:Substandard


None
Period End2020-06-302020-03-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.2382.0430.2140.3020.3470.370.370.6360.2820.2820.2820.203
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.10.10.00.00.00.00.00.00.00.00.00.0

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value12871083764796535411336405397244224233275
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome31.030.825.328.922.718.916.421.221.615.616.419.329.2

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-30
Value0.224
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.0

mbin:MortgageWarehouseLinesOfCreditPortfolioSegment, us-gaap:Substandard


None
Period End2020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value0.230.2330.2370.5660.5720.5750.5790.8040.933
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.00.00.00.00.00.00.00.00.1

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1767140413051106959908842693668629527391261
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome42.539.943.140.240.641.640.936.136.440.038.432.427.7

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-30
Value333041384256714534151.81.8
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.80.91.41.41.82.63.52.41.91.00.10.1

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value397446375278295275275267251229209195101
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome9.612.712.410.112.512.613.414.013.714.615.316.210.8

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1012131111121415131312107.15
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.30.40.50.40.50.60.70.80.70.90.90.90.8

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:Substandard


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value9.0199.4259.1528.4377.8848.1868.5766.9746.5396.4666.1794.4414.986
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.20.30.30.30.30.40.40.40.40.40.40.40.5

us-gaap:ConsumerPortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value1418181920161610109.4827.711107.234
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.40.50.60.70.90.80.80.50.60.60.60.80.8

us-gaap:ConsumerPortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value0.0280.030.0310.0380.020.3810.6811.2611.5891.6011.5631.8822.158
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.00.00.00.00.00.00.00.10.10.10.10.20.2

us-gaap:ConsumerPortfolioSegment, us-gaap:Substandard


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-31
Value0.0190.0160.0230.0250.0530.050.0580.1870.1960.1460.146
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.00.00.00.00.00.00.00.00.00.00.0

us-gaap:ResidentialPortfolioSegment, us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value468417408404396404408398378355329307235
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome11.311.813.514.716.818.519.920.820.722.624.025.425.0

us-gaap:ResidentialPortfolioSegment, us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-09-302016-12-31
Value0.7212.4132.4720.6740.6430.590.4430.3010.3060.5460.2090.214
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.00.10.10.00.00.00.00.00.00.00.00.0

us-gaap:ResidentialPortfolioSegment, us-gaap:Substandard


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value2.8272.413.1095.1615.0264.2551.6061.0481.0660.7280.7290.2460.343
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.10.10.10.20.20.20.10.10.10.00.10.00.0

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome us-gaap:FinancingReceivablePortfolioSegment, us-gaap:InternalCreditAssessment, us-gaap:UnusualOrInfrequentItem

mbin:MultiFamilyAndHealthcareFinancingPortfolioSegment, us-gaap:SpecialMention, mbin:Covid19


None
Period End2020-06-30
Value48
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome1.2

us-gaap:CommercialRealEstatePortfolioSegment, us-gaap:SpecialMention, mbin:Covid19


None
Period End2020-06-30
Value15
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.4

us-gaap:ConsumerPortfolioSegment, us-gaap:SpecialMention, mbin:Covid19


None
Period End2020-06-30
Value0.092
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.0

us-gaap:ResidentialPortfolioSegment, us-gaap:SpecialMention, mbin:Covid19


None
Period End2020-06-30
Value0.136
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.0

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome us-gaap:InternalCreditAssessment

us-gaap:Pass


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value402934582955268522882095195618411772153113511189926
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome97.098.297.697.597.096.095.196.196.697.398.398.498.4

us-gaap:SpecialMention


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value4648605657739066523316149.522
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome1.11.42.02.02.43.44.43.52.92.11.21.21.0

us-gaap:Substandard


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value141412141313119.2679.3518.5557.3364.9695.532
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome0.30.40.40.50.60.60.50.50.50.50.50.40.6

us-gaap:LoansAndLeasesReceivableNetOfDeferredIncome us-gaap:InternalCreditAssessment, us-gaap:UnusualOrInfrequentItem

us-gaap:SpecialMention, mbin:Covid19


None
Period End2020-06-30
Value63
Percentage of LoansAndLeasesReceivableNetOfDeferredIncome1.5

us-gaap:LoansAndLeasesReceivableNetReportedAmount

us-gaap:LoansAndLeasesReceivableNetReportedAmount


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value413335013012274223472168204519051823156313661201935
Percentage of LoansAndLeasesReceivableNetReportedAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansHeldForSaleFairValueDisclosure

us-gaap:LoansHeldForSaleFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value421819239.5926.307115.888516.618
Percentage of LoansHeldForSaleFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansHeldForSaleFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:FairValueInputsLevel2, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value383527772074247519088758209989011074995798764
Percentage of LoansHeldForSaleFairValueDisclosure9132.814664.010587.010597.219897.113885.66903.716958.51741.216239.90.00.00.0

us-gaap:LoansHeldForSaleFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value421819239.5926.307115.888516.618
Percentage of LoansHeldForSaleFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansHeldForSaleFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value383527772074247519088758209989011074995798764
Percentage of LoansHeldForSaleFairValueDisclosure9132.814664.010587.010597.219897.113885.66903.716958.51741.216239.90.00.00.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value383527772074247519088758209989011074995798764
Percentage of LoansHeldForSaleFairValueDisclosure9132.814664.010587.010597.219897.113885.66903.716958.51741.216239.90.00.00.0

us-gaap:LoansHeldForSaleFairValueDisclosure us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-31
Value421819239.5926.307115.888516.618
Percentage of LoansHeldForSaleFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansReceivableFairValueDisclosure us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementBasis

us-gaap:LoansReceivableFairValueDisclosure

us-gaap:FairValueInputsLevel3, us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value412534752999272823382170204119131832156713641204935
Percentage of LoansReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansReceivableFairValueDisclosure us-gaap:FairValueByMeasurementBasis

us-gaap:CarryingReportedAmountFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value413335013012274223472168204519051823156313661201935
Percentage of LoansReceivableFairValueDisclosure100.2100.8100.4100.5100.499.9100.299.699.599.8100.199.8100.0

us-gaap:EstimateOfFairValueFairValueDisclosure


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value412534752999272823382170204119131832156713641204935
Percentage of LoansReceivableFairValueDisclosure100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:LoansReceivableHeldForSaleNetNotPartOfDisposalGroup

us-gaap:LoansReceivableHeldForSaleNetNotPartOfDisposalGroup


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value3877279620932498191888283210049531081995798764
Percentage of LoansReceivableHeldForSaleNetNotPartOfDisposalGroup100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:NoninterestBearingDepositLiabilities

us-gaap:NoninterestBearingDepositLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value601327272198192128182336585653620721566
Percentage of NoninterestBearingDepositLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:OtherLiabilities

us-gaap:OtherLiabilities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6168414854212017151813127.443
Percentage of OtherLiabilities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:PreferredStockValue us-gaap:StatementClassOfStock

us-gaap:PreferredStockValue

mbin:PreferredStock6


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value120120120120
Percentage of PreferredStockValue100.0100.0100.0100.0

mbin:PreferredStock7


None
Period End2020-06-302020-03-312019-12-312019-09-30
Value50505050
Percentage of PreferredStockValue41.641.641.641.6

us-gaap:SecuritiesPurchasedUnderAgreementsToResell

us-gaap:SecuritiesPurchasedUnderAgreementsToResell


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value6651000.06685000.06723000.06760000.06798000.06838000.06875000.06913000.06954000.07003000.07043000.07080000.05392000.0
Percentage of SecuritiesPurchasedUnderAgreementsToResell100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ServicingAssetAtFairValueAmount

us-gaap:ServicingAssetAtFairValueAmount


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-312015-12-312014-12-31
Value726974717476777170676662535552
Percentage of ServicingAssetAtFairValueAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ServicingAssetAtFairValueAmount us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel3, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value72697471747677717067666253
Percentage of ServicingAssetAtFairValueAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ServicingAssetAtFairValueAmount us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FiniteLivedIntangibleAssetsByMajorClass

us-gaap:FairValueInputsLevel3, us-gaap:ServicingContracts


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value72697471747677717067666253
Percentage of ServicingAssetAtFairValueAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ServicingAssetAtFairValueAmount us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value72697471747677717067666253
Percentage of ServicingAssetAtFairValueAmount100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:ServicingAssetMeasurementInput us-gaap:Range, us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FiniteLivedIntangibleAssetsByMajorClass, us-gaap:MeasurementInputType

us-gaap:ServicingAssetMeasurementInput

srt:Maximum, us-gaap:FairValueInputsLevel3, us-gaap:ServicingContracts, us-gaap:MeasurementInputConstantPrepaymentRate


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value0.450.430.390.390.350.3
Percentage of ServicingAssetMeasurementInput100.0100.0100.0100.0100.0100.0

srt:Minimum, us-gaap:FairValueInputsLevel3, us-gaap:ServicingContracts, us-gaap:MeasurementInputConstantPrepaymentRate


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value0.020.020.010.010.010.01
Percentage of ServicingAssetMeasurementInput4.44.72.62.62.93.3

srt:WeightedAverage, us-gaap:FairValueInputsLevel3, us-gaap:ServicingContracts, us-gaap:MeasurementInputConstantPrepaymentRate


None
Period End2020-06-30
Value0.04
Percentage of ServicingAssetMeasurementInput8.9

srt:WeightedAverage, us-gaap:FairValueInputsLevel3, us-gaap:ServicingContracts, us-gaap:MeasurementInputDiscountRate


None
Period End2020-06-30
Value0.08
Percentage of ServicingAssetMeasurementInput17.8

us-gaap:ServicingAssetMeasurementInput us-gaap:Range, us-gaap:FiniteLivedIntangibleAssetsByMajorClass, us-gaap:MeasurementInputType

srt:Minimum, us-gaap:ServicingContracts, us-gaap:MeasurementInputDiscountRate


None
Period End2020-03-31
Value0.08
Percentage of ServicingAssetMeasurementInput18.6

us-gaap:TierOneLeverageCapital dei:LegalEntity

us-gaap:TierOneLeverageCapital

mbin:JoyStateBank


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value22212119181817
Percentage of TierOneLeverageCapital100.0100.0100.0100.0100.0100.0100.0

mbin:MerchantsBankOfIndiana


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312017-09-302016-12-31
Value680642623600504465399398275249
Percentage of TierOneLeverageCapital3000.92926.42932.13050.92666.22455.12297.30.00.00.0

us-gaap:TierOneLeverageCapital us-gaap:ConsolidatedEntities

srt:ParentCompany


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value688652621596478380
Percentage of TierOneLeverageCapital3039.72971.42922.33031.22530.92188.9

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalized dei:LegalEntity

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalized

mbin:JoyStateBank


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value19189.1288.5568.1157.988.066
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalized100.0100.0100.0100.0100.0100.0100.0

mbin:MerchantsBankOfIndiana


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312017-09-302016-12-31
Value674574321290223175182159158147
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalized3546.13121.53526.13400.42755.72198.42258.30.00.00.0

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalized us-gaap:ConsolidatedEntities

srt:ParentCompany


None
Period End2020-06-302020-03-31
Value693592
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalized3645.93221.5

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets dei:LegalEntity

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets

mbin:JoyStateBank


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.080.090.050.050.050.050.05
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets100.0100.0100.0100.0100.0100.0100.0

mbin:MerchantsBankOfIndiana


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312017-09-302016-12-31
Value0.080.090.050.050.050.050.050.050.050.05
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets100.0100.0100.0100.0100.0100.0100.00.00.00.0

us-gaap:TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets us-gaap:ConsolidatedEntities

srt:ParentCompany


None
Period End2020-06-302020-03-31
Value0.080.09
Percentage of TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets100.0100.0

us-gaap:TierOneLeverageCapitalToAverageAssets dei:LegalEntity

us-gaap:TierOneLeverageCapitalToAverageAssets

mbin:JoyStateBank


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-31
Value0.0950.1070.1170.1150.1170.1190.108
Percentage of TierOneLeverageCapitalToAverageAssets100.0100.0100.0100.0100.0100.0100.0

mbin:MerchantsBankOfIndiana


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312017-12-312017-09-302016-12-31
Value0.0810.1010.0970.1030.1130.1330.110.1250.0870.084
Percentage of TierOneLeverageCapitalToAverageAssets85.394.482.989.696.6111.8101.90.00.00.0

us-gaap:TierOneLeverageCapitalToAverageAssets us-gaap:ConsolidatedEntities

srt:ParentCompany


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302018-12-31
Value0.0790.0990.0940.10.1030.1
Percentage of TierOneLeverageCapitalToAverageAssets83.292.580.387.088.092.6

us-gaap:TradingSecurities

us-gaap:TradingSecurities


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value51846526922710112916374135200140121137
Percentage of TradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TradingSecurities us-gaap:FairValueByFairValueHierarchyLevel, us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueInputsLevel2, us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value51846526922710112916374135200140121137
Percentage of TradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

us-gaap:TradingSecurities us-gaap:FairValueByMeasurementFrequency

us-gaap:FairValueMeasurementsRecurring


None
Period End2020-06-302020-03-312019-12-312019-09-302019-06-302019-03-312018-12-312018-09-302018-06-302018-03-312017-12-312017-09-302016-12-31
Value51846526922710112916374135200140121137
Percentage of TradingSecurities100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0100.0

Line plots across dimensions of each concept


us-gaap:InterestExpense
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:InterestIncomeExpenseNet
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:IncomeTaxExpenseBenefit
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:NetIncomeLoss
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
EBT Margin
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:Assets
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None
us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents
(None,)
None
us-gaap:StockholdersEquity
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
(None, 'us-gaap:PreferredStock')
None
us-gaap:StockholdersEquity
us-gaap:StatementEquityComponents
(None,)
None
us-gaap:StockholdersEquity
us-gaap:StatementClassOfStock, us-gaap:StatementEquityComponents
(None, 'us-gaap:PreferredStock')
None
us-gaap:NetIncomeLoss
us-gaap:ConsolidationItems, us-gaap:StatementBusinessSegments
('us-gaap:OperatingSegments', None)
None