Quarterly report pursuant to Section 13 or 15(d)

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

v2.4.0.8
Description of Business, Basis of Presentation and Accounting Policies - Additional Information (Detail)
9 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2013
Sep. 30, 2013
Total revenues [Member]
Sep. 30, 2012
Total revenues [Member]
Sep. 30, 2013
Total revenues [Member]
Sep. 30, 2012
Total revenues [Member]
Sep. 30, 2013
Minimum [Member]
Commissions receivable [Member]
Dec. 31, 2012
Minimum [Member]
Commissions receivable [Member]
Product Information [Line Items]              
IPO completion date Nov. 05, 2013            
Formation date 2013-06            
Customer risk percentage   10.00% 10.00% 10.00% 10.00% 10.00% 10.00%