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

Quarterly report pursuant to Section 13 or 15(d)

Cover
- Document and Entity Information
Financial Statements
Notes to Financial Statements
Accounting Policies
- Description of Business and Basis of Presentation (Policies)
Notes Tables
Notes Details

Accounting Policies and Recent Accounting Pronouncements - Additional Information (Detail)

v3.8.0.1

Accounting Policies and Recent Accounting Pronouncements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2018 USD ($) Office	Mar. 31, 2017 Office	Dec. 31, 2017 USD ($)
Accounting Policies [Line Items]
Commission's receivable settled period	10 days
Marketable securities, available for sale	$ 130,399,000		$ 125,659,000
Accounting Standards Update 2018-02 [Member]
Accounting Policies [Line Items]
Reclassification of stranded tax effects from accumulated other comprehensive income to retained earnings	13,000
Accounting Standards Update 2016-02 [Member]
Accounting Policies [Line Items]
Operating lease obligations	$ 83,600,000
Customer Concentration Risk [Member] \| Total revenues [Member]
Accounting Policies [Line Items]
Concentration risk percentage	10.00%	10.00%
Customer Concentration Risk [Member] \| Commissions receivable [Member]
Accounting Policies [Line Items]
Concentration risk percentage	10.00%	10.00%
Geographic Concentration Risk [Member] \| Total revenues [Member]
Accounting Policies [Line Items]
Concentration risk percentage	10.00%	10.00%
Number of offices \| Office	0	0
Capitalization of Internal Labor [Member] \| Maximum [Member]
Accounting Policies [Line Items]
Property and equipment, estimated useful life	7 years
Capitalization of Internal Labor [Member] \| Minimum [Member]
Accounting Policies [Line Items]
Property and equipment, estimated useful life	3 years
Average AA Credit Rating [Member] \| Accounting Standards Update 2016-13 [Member]
Accounting Policies [Line Items]
Marketable securities, available for sale	$ 130,400,000
Impairment write-downs marketable securities, available for sale	$ 0
International Revenues [Member] \| Maximum [Member] \| Geographic Concentration Risk [Member] \| Total revenues [Member]
Accounting Policies [Line Items]
Concentration risk percentage	1.00%	1.00%

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