Marcus & Millichap, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Additional Information Credit Agreement (Detail)

Commitments and Contingencies - Additional Information Credit Agreement (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015 Ratio	Mar. 31, 2014
Line of Credit Facility [Line Items]
Senior secured revolving credit facility maximum borrowing capacity	$ 60,000,000
Revolving credit facility maturity date	Jun. 01, 2017
Bank fees and other expenses	224,000us-gaap_DeferredFinanceCostsGross
Credit agreement, unused capacity, commitment fee percentage	0.10%
Commitment fee commencement date	Jul. 01, 2014
Date the Company entered into a Credit Agreement	Jun. 18, 2014
Credit agreement date	Jun. 01, 2014
Interest expense	583,000us-gaap_InterestExpense	404,000us-gaap_InterestExpense
Credit agreement, amount outstanding	0us-gaap_LineOfCredit
Standby letters of credit borrowing capacity	10,000,000mmi_StandbyLettersOfCreditSublimit
Credit facility interest rate description	Credit Facility will bear interest, at the Company's option, at either the (i) Base Rate (defined as the highest of (a) the Bank's prime rate, (b) the Federal Funds Rate plus 1.5% and (c) one-month LIBOR plus 1.5%), or (ii) at a variable rate between 0.875% and 1.125% above LIBOR, based upon the total funded debt to EBITDA ratio.
LIBOR rate duration period	1 month
Credit facility covenants	(i) an EBITDAR Coverage Ratio (as defined in the Credit Agreement) of not less than 1.251.0 as of each quarter end on a rolling 4-quarter basis and (ii) total funded debt to EBITDA not greater than 2.01.0
Minimum EBITDAR coverage ratio	1.25mmi_MinimumEbitdarCoverageRatio
Maximum Total Funded Debt to EBITDA ratio	2.0mmi_MaximumFundedDebtToEbitdaRatio
Credit agreement, pledge percentage	100.00%mmi_CreditFacilityPledgePercentage
Compliance description	As of March 31, 2015, the Company was in compliance with all financial and non-financial covenants.
London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Base spread on variable rate	1.50%
Credit Agreement [Member]
Line of Credit Facility [Line Items]
Interest expense	$ 34,000
Federal Funds Rate [Member]
Line of Credit Facility [Line Items]
Base spread on variable rate	1.50%
Minimum [Member] \| Variable Rate [Member]
Line of Credit Facility [Line Items]
Base spread on variable rate	0.875%
Maximum [Member] \| Variable Rate [Member]
Line of Credit Facility [Line Items]
Base spread on variable rate	1.125%