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

Description of Business, Basis of Presentation and Recent Accounting Pronouncements - Additional Information (Detail)

v3.5.0.2

Description of Business, Basis of Presentation and Recent Accounting Pronouncements - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015	Jun. 30, 2016 USD ($) Office	Jun. 30, 2015
Class of Stock [Line Items]
Number of offices in the United States and Canada \| Office			81
Formation date			2013-06
Percentage of common stock distributed			80.00%
IPO completion date			Oct. 30, 2013
Commission's receivable settled period			10 days
Operating lease obligations \| $	$ 80.3		$ 80.3
Customer Concentration Risk [Member] \| Total revenues [Member]
Class of Stock [Line Items]
Concentration of credit risk percentage	10.00%	10.00%	10.00%	10.00%
Customer Concentration Risk [Member] \| Commissions receivable [Member]
Class of Stock [Line Items]
Concentration of credit risk percentage	10.00%	10.00%	10.00%	10.00%
Geographic Concentration Risk [Member] \| Total revenues [Member] \| Maximum [Member] \| CANADA
Class of Stock [Line Items]
Concentration of credit risk percentage			1.00%

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