Annual report pursuant to Section 13 and 15(d)

Related-Party Transactions - Additional Information (Detail)

v3.10.0.1
Related-Party Transactions - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Related Party Transaction [Line Items]      
Rent expense for lease $ 27,700,000 $ 25,600,000 $ 23,400,000
Aggregate principal amount for employee notes receivable 526,000 621,000  
MMC [Member]      
Related Party Transaction [Line Items]      
Real estate brokerage commissions and financing fees from transactions with subsidiaries of Marcus & Millichap Company 7,700,000 2,100,000 5,100,000
Commission expenses for transactions with subsidiaries of Marcus & Millichap Company 4,600,000 1,200,000 3,000,000
Rent expense for lease $ 1,000,000 1,000,000 1,000,000
Lease expiration date May 31, 2022    
Accounts payable and other liabilities - related party $ 101,000 91,000  
MMC [Member] | Transition Services Agreement [Member]      
Related Party Transaction [Line Items]      
Selling, general and administrative expense $ 197,000 $ 210,000 $ 227,000
Transition services agreement date Oct. 01, 2013    
George M. Marcus [Member]      
Related Party Transaction [Line Items]      
Beneficial ownership percentage 41.00%