Quarterly report pursuant to Section 13 or 15(d)

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

v3.3.0.814
Description of Business, Basis of Presentation and Recent Accounting Pronouncements - Additional Information (Detail) - Office
3 Months Ended 9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Sep. 30, 2015
Sep. 30, 2014
Class of Stock [Line Items]        
Number of offices in the United States and Canada     80  
Formation date     2013-06  
Contribution date     Oct. 30, 2013  
Percentage of common stock distributed     80.00%  
Commission's receivable settled period     10 days  
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%