Annual report pursuant to Section 13 and 15(d)

FAIR VALUE (Details)

v2.4.1.9
FAIR VALUE (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Minimum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Capitalization rate (in hundredths)   9.50%us-gaap_FairValueInputsCapRate
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Maximum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Capitalization rate (in hundredths)   12.00%us-gaap_FairValueInputsCapRate
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Income Approach [Member] | Minimum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Capitalization rate (in hundredths) 9.50%us-gaap_FairValueInputsCapRate
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Income Approach [Member] | Maximum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Capitalization rate (in hundredths) 12.00%us-gaap_FairValueInputsCapRate
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Impaired Loans [Member] | Sales Comparison Approach [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Asset (liability) fair value 12,649us-gaap_AssetsFairValueDisclosure
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Impaired Loans [Member] | Sales Comparison Approach [Member] | Minimum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Adjustment for differences between comparable sales (in hundredths) 1.00%us-gaap_FairValueInputsComparabilityAdjustments
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Impaired Loans [Member] | Sales Comparison Approach [Member] | Maximum [Member]    
Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Adjustment for differences between comparable sales (in hundredths) 20.00%us-gaap_FairValueInputsComparabilityAdjustments
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Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Asset (liability) fair value 22,472us-gaap_AssetsFairValueDisclosure
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Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Adjustment for differences between comparable sales (in hundredths) 3.00%us-gaap_FairValueInputsComparabilityAdjustments
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Fair Value Inputs, Assets, Quantitative Information [Line Items]    
Adjustment for differences between comparable sales (in hundredths) 22.70%us-gaap_FairValueInputsComparabilityAdjustments
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Recurring Basis [Member]    
Asset measured at fair value on recurring basis [Abstract]    
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Loans held for sale 2,347us-gaap_LoansHeldForSaleFairValueDisclosure
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Interest rate swaps (140)us-gaap_InterestRateDerivativeLiabilitiesAtFairValue
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Recurring Basis [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Asset measured at fair value on recurring basis [Abstract]    
U.S. Treasury and federal agency securities 0mcbc_UnitedStatesGovernmentTreasuryAndFederalAgencySecuritiesFairValueDisclosure
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Asset measured at fair value on recurring basis [Abstract]    
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Asset measured at fair value on recurring basis [Abstract]    
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Asset measured at fair value on non-recurring basis [Abstract]    
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Asset measured at fair value on non-recurring basis [Abstract]    
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Nonrecurring Basis [Member] | Significant Other Observable Inputs (Level 2) [Member]    
Asset measured at fair value on non-recurring basis [Abstract]    
Impaired loans 0mcbc_ImpairedLoansFairValueDisclosure
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Nonrecurring Basis [Member] | Significant Unobservable Inputs (Level 3) [Member]    
Asset measured at fair value on non-recurring basis [Abstract]    
Impaired loans 12,649mcbc_ImpairedLoansFairValueDisclosure
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