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

Stock-Based Compensation Plans - Employee Stock Purchase Plans - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payroll deductions maximum percentage to purchase shares on common stock on purchase dates	15.00%
Maximum shares of common stock purchase during each purchase period	1,250
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved and available for issuance	366,667
Common stock available for future issuance authorized annual share increase	366,667
Common stock available for future issuance authorized annual percentage increase	1.00%
Length of purchase intervals	6 months
ESPP offering period description	The offering periods generally start on the first trading day on or after May 15 and November 15 of each year. The first offering period is expected to begin on May 15, 2014.