Annual report pursuant to Section 13 and 15(d)

CONDENSED FINANCIAL STATEMENTS (PARENT COMPANY ONLY) (Details)

v2.4.1.9
CONDENSED FINANCIAL STATEMENTS (PARENT COMPANY ONLY) (Details) (USD $)
0 Months Ended 3 Months Ended 12 Months Ended
Jun. 30, 2011
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2008
Dec. 31, 2009
Dec. 31, 2011
ASSETS                              
Cash and cash equivalents   $ 129,455,000us-gaap_CashAndCashEquivalentsAtCarryingValue       $ 156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue       $ 129,455,000us-gaap_CashAndCashEquivalentsAtCarryingValue $ 156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue $ 226,358,000us-gaap_CashAndCashEquivalentsAtCarryingValue      
Other assets   2,831,000us-gaap_OtherAssets       4,491,000us-gaap_OtherAssets       2,831,000us-gaap_OtherAssets 4,491,000us-gaap_OtherAssets        
Total assets   1,583,846,000us-gaap_Assets       1,517,405,000us-gaap_Assets       1,583,846,000us-gaap_Assets 1,517,405,000us-gaap_Assets        
LIABILITIES AND SHAREHOLDERS' EQUITY                              
Long-term debt   41,238,000us-gaap_LongTermDebt       41,238,000us-gaap_LongTermDebt       41,238,000us-gaap_LongTermDebt 41,238,000us-gaap_LongTermDebt        
Total liabilities   1,441,327,000us-gaap_Liabilities       1,384,883,000us-gaap_Liabilities       1,441,327,000us-gaap_Liabilities 1,384,883,000us-gaap_Liabilities        
Total shareholders' equity   142,519,000us-gaap_StockholdersEquity       132,522,000us-gaap_StockholdersEquity       142,519,000us-gaap_StockholdersEquity 132,522,000us-gaap_StockholdersEquity 130,507,000us-gaap_StockholdersEquity     94,426,000us-gaap_StockholdersEquity
Total liabilities and shareholders' equity   1,583,846,000us-gaap_LiabilitiesAndStockholdersEquity       1,517,405,000us-gaap_LiabilitiesAndStockholdersEquity       1,583,846,000us-gaap_LiabilitiesAndStockholdersEquity 1,517,405,000us-gaap_LiabilitiesAndStockholdersEquity        
Expense                              
Interest expense                   5,596,000us-gaap_InterestExpense 7,337,000us-gaap_InterestExpense 9,814,000us-gaap_InterestExpense      
Income tax benefit                   4,573,000us-gaap_IncomeTaxExpenseBenefit 4,270,000us-gaap_IncomeTaxExpenseBenefit (18,583,000)us-gaap_IncomeTaxExpenseBenefit      
Net income   2,317,000us-gaap_NetIncomeLoss 2,762,000us-gaap_NetIncomeLoss 2,755,000us-gaap_NetIncomeLoss 2,639,000us-gaap_NetIncomeLoss 2,234,000us-gaap_NetIncomeLoss 2,238,000us-gaap_NetIncomeLoss 2,603,000us-gaap_NetIncomeLoss 2,473,000us-gaap_NetIncomeLoss 10,473,000us-gaap_NetIncomeLoss 9,549,000us-gaap_NetIncomeLoss 35,490,000us-gaap_NetIncomeLoss      
Net income (loss) available to common shares                   10,473,000us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic (8,026,000)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic 35,490,000us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic      
Comprehensive income                   12,489,000us-gaap_ComprehensiveIncomeNetOfTax 6,634,000us-gaap_ComprehensiveIncomeNetOfTax 36,072,000us-gaap_ComprehensiveIncomeNetOfTax      
Cash flows from operating activities                              
Net income   2,317,000us-gaap_NetIncomeLoss 2,762,000us-gaap_NetIncomeLoss 2,755,000us-gaap_NetIncomeLoss 2,639,000us-gaap_NetIncomeLoss 2,234,000us-gaap_NetIncomeLoss 2,238,000us-gaap_NetIncomeLoss 2,603,000us-gaap_NetIncomeLoss 2,473,000us-gaap_NetIncomeLoss 10,473,000us-gaap_NetIncomeLoss 9,549,000us-gaap_NetIncomeLoss 35,490,000us-gaap_NetIncomeLoss      
Adjustments to reconcile net income to net cash from operating activities:                              
Stock compensation expense                   338,000us-gaap_ShareBasedCompensation 160,000us-gaap_ShareBasedCompensation 9,000us-gaap_ShareBasedCompensation      
Net cash from operating activities                   16,618,000us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations 16,312,000us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations 13,495,000us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations      
Cash flows from investing activities                              
Net cash from investing activities                   (95,806,000)us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations (40,991,000)us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations (44,048,000)us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations      
Cash flows from financing activities                              
Proceeds from issuance of common stock 20,300,000us-gaap_ProceedsFromIssuanceOfCommonStock                 4,000us-gaap_ProceedsFromIssuanceOfCommonStock 0us-gaap_ProceedsFromIssuanceOfCommonStock 0us-gaap_ProceedsFromIssuanceOfCommonStock      
Cash dividends paid                   (2,689,000)us-gaap_PaymentsOfDividends 0us-gaap_PaymentsOfDividends 0us-gaap_PaymentsOfDividends      
Common stock issuance costs                   (102,000)us-gaap_PaymentsOfStockIssuanceCosts 0us-gaap_PaymentsOfStockIssuanceCosts 0us-gaap_PaymentsOfStockIssuanceCosts      
Repurchases of shares                   (106,000)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation (45,000)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation 0us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation      
Cash paid in preferred stock exchange                   0mcbc_CashPaidInPreferredStockExchange (4,734,000)mcbc_CashPaidInPreferredStockExchange 0mcbc_CashPaidInPreferredStockExchange      
Net cash from financing activities                   51,751,000us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations (44,787,000)us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations 13,869,000us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations      
Net change in cash and cash equivalents                   (27,437,000)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease (69,466,000)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease (16,684,000)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease      
Cash and cash equivalents at beginning of period         156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue       226,358,000us-gaap_CashAndCashEquivalentsAtCarryingValue 156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue 226,358,000us-gaap_CashAndCashEquivalentsAtCarryingValue 243,042,000us-gaap_CashAndCashEquivalentsAtCarryingValue      
Cash and cash equivalents at end of period   129,455,000us-gaap_CashAndCashEquivalentsAtCarryingValue       156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue       129,455,000us-gaap_CashAndCashEquivalentsAtCarryingValue 156,892,000us-gaap_CashAndCashEquivalentsAtCarryingValue 226,358,000us-gaap_CashAndCashEquivalentsAtCarryingValue      
Supplemental noncash disclosures:                              
Exchange of 31,290 shares of Preferred Series A to 5,973,519 shares of common stock                   0mcbc_PreferredStockSeriesAExchangedForCommonStock 30,604,000mcbc_PreferredStockSeriesAExchangedForCommonStock 0mcbc_PreferredStockSeriesAExchangedForCommonStock      
Exchange of 2,300 shares of Preferred Series B to 457,159 shares of common stock                   0mcbc_PreferredStockSeriesBExchangedForCommonStock 2,260,000mcbc_PreferredStockSeriesBExchangedForCommonStock 0mcbc_PreferredStockSeriesBExchangedForCommonStock      
Series A [Member]                              
Cash flows from financing activities                              
Common stock issuance costs                         (686,000)us-gaap_PaymentsOfStockIssuanceCosts
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
   
Supplemental noncash disclosures:                              
Number of shares converted in conversion of Preferred Stock to Common Stock (in shares)                   5,973,519us-gaap_ConversionOfStockSharesConverted1
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
         
Series B [Member]                              
Cash flows from financing activities                              
Common stock issuance costs                           (40,000)us-gaap_PaymentsOfStockIssuanceCosts
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
 
Supplemental noncash disclosures:                              
Number of shares exchanged in exchange of Preferred Stock to Common Stock (in shares)                   457,519mcbc_ExchangeOfStockSharesExchanged
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
         
Preferred Stock [Member] | Series A [Member]                              
LIABILITIES AND SHAREHOLDERS' EQUITY                              
Total shareholders' equity   0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
      0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
      0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
30,604,000us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
    30,604,000us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
Preferred Stock [Member] | Series B [Member]                              
LIABILITIES AND SHAREHOLDERS' EQUITY                              
Total shareholders' equity   0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
      0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
      0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
0us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
2,560,000us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
    2,560,000us-gaap_StockholdersEquity
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
Common Stock [Member]                              
LIABILITIES AND SHAREHOLDERS' EQUITY                              
Total shareholders' equity   216,460,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
      216,263,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
      216,460,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
216,263,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
187,718,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
    187,709,000us-gaap_StockholdersEquity
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
Cash flows from financing activities                              
Common stock issuance costs                   (102,000)us-gaap_PaymentsOfStockIssuanceCosts
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
         
Conversion of Preferred Stock Series B to Common Stock [Member] | Preferred Stock [Member] | Series B [Member]                              
Supplemental noncash disclosures:                              
Number of shares converted in conversion of Preferred Stock to Common Stock (in shares)                     300us-gaap_ConversionOfStockSharesConverted1
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ConversionOfPreferredStockSeriesBToCommonStockMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Conversion of Preferred Stock Series B to Common Stock [Member] | Common Stock [Member]                              
Supplemental noncash disclosures:                              
Number of shares issued in conversion of Preferred Stock to Common Stock (in shares)                     50,000us-gaap_ConversionOfStockSharesIssued1
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ConversionOfPreferredStockSeriesBToCommonStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
       
Exchange of Preferred Stock Series A to Common Stock [Member] | Preferred Stock [Member] | Series A [Member]                              
Supplemental noncash disclosures:                              
Number of shares exchanged in exchange of Preferred Stock to Common Stock (in shares)                     31,290mcbc_ExchangeOfStockSharesExchanged
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesAToCommonStockMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Exchange of Preferred Stock Series A to Common Stock [Member] | Common Stock [Member]                              
Supplemental noncash disclosures:                              
Number of shares issued in exchange of Preferred Stock to Common Stock (in shares)                     5,973,519mcbc_ExchangeOfStockSharesIssued
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesAToCommonStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
       
Exchange of Preferred Stock Series B to Common Stock [Member] | Preferred Stock [Member] | Series B [Member]                              
Supplemental noncash disclosures:                              
Number of shares exchanged in exchange of Preferred Stock to Common Stock (in shares)                     2,300mcbc_ExchangeOfStockSharesExchanged
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesBToCommonStockMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Exchange of Preferred Stock Series B to Common Stock [Member] | Common Stock [Member]                              
Supplemental noncash disclosures:                              
Number of shares issued in exchange of Preferred Stock to Common Stock (in shares)                     457,159mcbc_ExchangeOfStockSharesIssued
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesBToCommonStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
       
Parent Company [Member]                              
ASSETS                              
Cash and cash equivalents   2,544,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      2,544,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
9,787,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Investments in Bank subsidiary   177,312,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      167,292,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      177,312,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
167,292,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAtFairValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Investment in other subsidiaries   1,491,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      1,504,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      1,491,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,504,000us-gaap_InvestmentsInAndAdvancesToAffiliatesAmountOfEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Other assets   2,599,000us-gaap_OtherAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      3,272,000us-gaap_OtherAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      2,599,000us-gaap_OtherAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
3,272,000us-gaap_OtherAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Total assets   183,946,000us-gaap_Assets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      173,978,000us-gaap_Assets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      183,946,000us-gaap_Assets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
173,978,000us-gaap_Assets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
LIABILITIES AND SHAREHOLDERS' EQUITY                              
Long-term debt   41,238,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      41,238,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      41,238,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
41,238,000us-gaap_LongTermDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Other liabilities   189,000us-gaap_OtherLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      218,000us-gaap_OtherLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      189,000us-gaap_OtherLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
218,000us-gaap_OtherLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Total liabilities   41,427,000us-gaap_Liabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      41,456,000us-gaap_Liabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      41,427,000us-gaap_Liabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
41,456,000us-gaap_Liabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Total shareholders' equity   142,519,000us-gaap_StockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      132,522,000us-gaap_StockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      142,519,000us-gaap_StockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
132,522,000us-gaap_StockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Total liabilities and shareholders' equity   183,946,000us-gaap_LiabilitiesAndStockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      173,978,000us-gaap_LiabilitiesAndStockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      183,946,000us-gaap_LiabilitiesAndStockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
173,978,000us-gaap_LiabilitiesAndStockholdersEquity
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
       
Income                              
Dividends from subsidiaries                   4,139,000us-gaap_CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
5,179,000us-gaap_CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Other                   0us-gaap_OtherOperatingIncome
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_OtherOperatingIncome
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_OtherOperatingIncome
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Total income                   4,139,000us-gaap_FinancialServicesRevenue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
5,179,000us-gaap_FinancialServicesRevenue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_FinancialServicesRevenue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Expense                              
Interest expense                   1,311,000us-gaap_InterestExpense
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,563,000us-gaap_InterestExpense
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,719,000us-gaap_InterestExpense
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Other expense                   611,000us-gaap_OtherExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
575,000us-gaap_OtherExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
555,000us-gaap_OtherExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Total expense                   1,922,000us-gaap_OperatingCostsAndExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
2,138,000us-gaap_OperatingCostsAndExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
2,274,000us-gaap_OperatingCostsAndExpenses
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Income (loss) before income tax and equity in undistributed earnings of subsidiaries                   2,217,000us-gaap_IncomeLossFromContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
3,041,000us-gaap_IncomeLossFromContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(2,274,000)us-gaap_IncomeLossFromContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Equity in undistributed earnings of subsidiaries                   7,592,000us-gaap_UndistributedEarnings
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
5,770,000us-gaap_UndistributedEarnings
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
35,338,000us-gaap_UndistributedEarnings
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Income before income tax                   9,809,000us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
8,811,000us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
33,064,000us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Income tax benefit                   (664,000)us-gaap_IncomeTaxExpenseBenefit
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(738,000)us-gaap_IncomeTaxExpenseBenefit
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(2,426,000)us-gaap_IncomeTaxExpenseBenefit
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net income                   10,473,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
9,549,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
35,490,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net income (loss) available to common shares                   10,473,000us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(8,026,000)us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
35,490,000us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Comprehensive income                   12,489,000us-gaap_ComprehensiveIncomeNetOfTax
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
6,634,000us-gaap_ComprehensiveIncomeNetOfTax
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
36,072,000us-gaap_ComprehensiveIncomeNetOfTax
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash flows from operating activities                              
Net income                   10,473,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
9,549,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
35,490,000us-gaap_NetIncomeLoss
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Adjustments to reconcile net income to net cash from operating activities:                              
Equity in undistributed earnings of subsidiaries                   (7,592,000)us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(5,770,000)us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(35,338,000)us-gaap_IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Stock compensation expense                   2,000us-gaap_ShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_ShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_ShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Change in other assets                   673,000us-gaap_IncreaseDecreaseInOtherOperatingAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(740,000)us-gaap_IncreaseDecreaseInOtherOperatingAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(2,424,000)us-gaap_IncreaseDecreaseInOtherOperatingAssets
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Change in other liabilities                   (29,000)us-gaap_IncreaseDecreaseInOtherOperatingLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(4,487,000)us-gaap_IncreaseDecreaseInOtherOperatingLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,524,000us-gaap_IncreaseDecreaseInOtherOperatingLiabilities
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net cash from operating activities                   3,527,000us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(1,448,000)us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(748,000)us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash flows from investing activities                              
Investment in subsidiaries                   0us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsToAcquireInterestInSubsidiariesAndAffiliates
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net cash from investing activities                   0us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash flows from financing activities                              
Proceeds from issuance of common stock                   4,000us-gaap_ProceedsFromIssuanceOfCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_ProceedsFromIssuanceOfCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_ProceedsFromIssuanceOfCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash dividends paid                   (2,689,000)us-gaap_PaymentsOfDividends
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsOfDividends
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsOfDividends
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Common stock issuance costs                   (102,000)us-gaap_PaymentsOfStockIssuanceCosts
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsOfStockIssuanceCosts
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsOfStockIssuanceCosts
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Redemption of subordinated debt                   0us-gaap_RepaymentsOfSubordinatedDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(1,650,000)us-gaap_RepaymentsOfSubordinatedDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_RepaymentsOfSubordinatedDebt
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Repurchases of shares                   (106,000)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(45,000)us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash paid in preferred stock exchange                   0mcbc_CashPaidInPreferredStockExchange
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(4,734,000)mcbc_CashPaidInPreferredStockExchange
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0mcbc_CashPaidInPreferredStockExchange
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net cash from financing activities                   (2,893,000)us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(6,429,000)us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Net change in cash and cash equivalents                   634,000us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(7,877,000)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
(748,000)us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash and cash equivalents at beginning of period         1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      9,787,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
9,787,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
10,535,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Cash and cash equivalents at end of period   2,544,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
      2,544,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
1,910,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
9,787,000us-gaap_CashAndCashEquivalentsAtCarryingValue
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Supplemental noncash disclosures:                              
Conversion of 300 shares of Preferred Series B to 50,000 shares of common stock                   0mcbc_ConversionOfPreferredStockToCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
300,000mcbc_ConversionOfPreferredStockToCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0mcbc_ConversionOfPreferredStockToCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Exchange of 31,290 shares of Preferred Series A to 5,973,519 shares of common stock                   0mcbc_PreferredStockSeriesAExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
30,604,000mcbc_PreferredStockSeriesAExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
0mcbc_PreferredStockSeriesAExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Exchange of 2,300 shares of Preferred Series B to 457,159 shares of common stock                   $ 0mcbc_PreferredStockSeriesBExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
$ 2,260,000mcbc_PreferredStockSeriesBExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
$ 0mcbc_PreferredStockSeriesBExchangedForCommonStock
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
     
Parent Company [Member] | Conversion of Preferred Stock Series B to Common Stock [Member] | Preferred Stock [Member] | Series B [Member]                              
Supplemental noncash disclosures:                              
Number of shares converted in conversion of Preferred Stock to Common Stock (in shares)                     300us-gaap_ConversionOfStockSharesConverted1
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ConversionOfPreferredStockSeriesBToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Parent Company [Member] | Exchange of Preferred Stock Series A to Common Stock [Member] | Preferred Stock [Member] | Series A [Member]                              
Supplemental noncash disclosures:                              
Number of shares exchanged in exchange of Preferred Stock to Common Stock (in shares)                     31,290mcbc_ExchangeOfStockSharesExchanged
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesAToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesAPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Parent Company [Member] | Exchange of Preferred Stock Series A to Common Stock [Member] | Common Stock [Member]                              
Supplemental noncash disclosures:                              
Number of shares issued in exchange of Preferred Stock to Common Stock (in shares)                     5,973,519mcbc_ExchangeOfStockSharesIssued
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesAToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
       
Parent Company [Member] | Exchange of Preferred Stock Series B to Common Stock [Member] | Preferred Stock [Member] | Series B [Member]                              
Supplemental noncash disclosures:                              
Number of shares exchanged in exchange of Preferred Stock to Common Stock (in shares)                     2,300mcbc_ExchangeOfStockSharesExchanged
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesBToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_SeriesBPreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
       
Parent Company [Member] | Exchange of Preferred Stock Series B to Common Stock [Member] | Common Stock [Member]                              
Supplemental noncash disclosures:                              
Number of shares issued in conversion of Preferred Stock to Common Stock (in shares)                     50,000us-gaap_ConversionOfStockSharesIssued1
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesBToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
       
Number of shares issued in exchange of Preferred Stock to Common Stock (in shares)                     457,159mcbc_ExchangeOfStockSharesIssued
/ us-gaap_ConversionOfStockByUniqueDescriptionAxis
= mcbc_ExchangeOfPreferredStockSeriesBToCommonStockMember
/ dei_LegalEntityAxis
= us-gaap_ParentCompanyMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember