Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Schedule of Deemed Capital Contribution (Distribution) (Detail)

v2.4.1.9
Stockholders' Equity - Schedule of Deemed Capital Contribution (Distribution) (Detail) (USD $)
10 Months Ended 12 Months Ended
Oct. 31, 2013
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2014
Mar. 31, 2013
Stockholders Equity [Line Items]          
SARs liability   $ (19,970,000)mmi_StockAppreciationRightsLiability   $ (20,542,000)mmi_StockAppreciationRightsLiability $ (20,000,000)mmi_StockAppreciationRightsLiability
Notes payable to former stockholders       (11,504,000)us-gaap_OtherNotesPayable  
Interest expense related to notes payable to former stockholders   (318,000)mmi_InterestExpenseRelatedToNotesPayablePriorToIpo      
Deferred taxes assets, net 26,600,000us-gaap_DeferredTaxAssetsLiabilitiesNet 26,572,000us-gaap_DeferredTaxAssetsLiabilitiesNet      
Deemed capital contribution in additional paid in capital (3,291,000)mmi_DeemedCapitalContributionDistribution (3,291,000)mmi_DeemedCapitalContributionDistribution 4,209,000mmi_DeemedCapitalContributionDistribution    
Unvested restricted stock and SARs [Member]          
Stockholders Equity [Line Items]          
Compensation cost for unvested restricted stock and SARs, net of tax   2,655,000us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
/ us-gaap_AwardTypeAxis
= mmi_UnvestedRestrictedStockAndStockAppreciationRightsSarsMember
4,209,000us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue
/ us-gaap_AwardTypeAxis
= mmi_UnvestedRestrictedStockAndStockAppreciationRightsSarsMember
   
Notes Payable APIC [Member]          
Stockholders Equity [Line Items]          
Notes payable to former stockholders   $ (12,230,000)us-gaap_OtherNotesPayable
/ us-gaap_DebtInstrumentAxis
= mmi_NotesPayableApicMember