Quarterly report pursuant to Section 13 or 15(d)

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)

v2.4.1.9
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)
3 Months Ended 12 Months Ended
Mar. 31, 2015
InterestRateSwap
Grade
Branch
Mar. 31, 2014
Dec. 31, 2014
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]      
Number of full service branch offices 26mcbc_NumberOfFullServiceBranchOffices    
Allowance for Loan Losses [Abstract]      
Period for annualized historical loss experience used for commercial loans 18 months    
Period of historical loss experience applied to residential mortgage and consumer loan portfolios 12 months    
Threshold for commercial and commercial real estate loans evaluated for impairment $ 500,000mcbc_ThresholdForCommercialAndCommercialRealEstateLoansEvaluatedForImpairment    
Minimum internal risk grading of commercial and commercial real estate loans evaluated for impairment 6mcbc_MinimumInternalRiskGradingOfCommercialAndCommercialRealEstateLoansEvaluatedForImpairment    
Income Taxes [Abstract]      
Percentage of more likely than not tax position that would be sustained in a tax examination (in hundredths) 50.00%mcbc_PercentageOfMoreLikelyThanNotTaxPositionThatWouldBeSustainedInTaxExamination    
Derivatives [Abstract]      
Number of freestanding interest rate swaps 2us-gaap_DerivativeNumberOfInstrumentsHeld    
Notional amount of agreements 20,000,000invest_DerivativeNotionalAmount   20,000,000invest_DerivativeNotionalAmount
Derivative asset fair value 224,000us-gaap_DerivativeFairValueOfDerivativeAsset   140,000us-gaap_DerivativeFairValueOfDerivativeAsset
Derivative liability fair value 224,000us-gaap_DerivativeAssetFairValueGrossLiability   140,000us-gaap_DerivativeAssetFairValueGrossLiability
Real Estate Properties [Line Items]      
Real estate properties classified as other real estate owned 699,000us-gaap_TransferToOtherRealEstate 554,000us-gaap_TransferToOtherRealEstate 4,932,000us-gaap_TransferToOtherRealEstate
Residential Real Estate [Member]      
Real Estate Properties [Line Items]      
Number of real estate properties classified as other real estate owned 4mcbc_NumberOfRealEstatePropertiesClassifiedAsOtherRealEstateOwned
/ us-gaap_RealEstatePropertiesAxis
= us-gaap_ResidentialRealEstateMember
   
Real estate properties classified as other real estate owned $ 595,000us-gaap_TransferToOtherRealEstate
/ us-gaap_RealEstatePropertiesAxis
= us-gaap_ResidentialRealEstateMember