Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets (Intangible Assets Subject To Amortization) (Detail)

v3.2.0.727
Intangible Assets (Intangible Assets Subject To Amortization) (Detail) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 10 years 4 days    
Gross Carrying Amount   $ 207,835 $ 174,259
Accumulated Amortization   $ 61,498 51,258
Technology      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 7 years 10 months 24 days    
Gross Carrying Amount $ 25,563   23,483
Accumulated Amortization $ 10,856   9,223
Relationships With Financial Advisors      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 15 years 2 months 12 days    
Gross Carrying Amount $ 110,671   81,438
Accumulated Amortization $ 27,811   23,704
Vendor Relationship      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 7 years    
Gross Carrying Amount $ 3,613   3,613
Accumulated Amortization $ 3,582   3,458
Covenants Not-to-Compete      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 3 years 10 months 24 days    
Gross Carrying Amount $ 5,908   5,401
Accumulated Amortization $ 2,710   2,100
Customer Account      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 8 years 3 months 18 days    
Gross Carrying Amount $ 2,029   2,029
Accumulated Amortization $ 1,640   1,516
Renewal revenue      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 7 years 9 months 18 days    
Gross Carrying Amount $ 39,503   39,503
Accumulated Amortization $ 4,617   2,099
Trade names      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 7 years 8 months 12 days    
Gross Carrying Amount $ 16,910   15,154
Accumulated Amortization $ 6,677   5,563
Relationships With Investment Banking Clients      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 4 years    
Gross Carrying Amount $ 2,586   2,586
Accumulated Amortization $ 2,586   2,586
Leases      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 6 years    
Gross Carrying Amount $ 861   861
Accumulated Amortization $ 861   861
Referral Agreement      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 6 years 7 months 6 days    
Gross Carrying Amount $ 124   124
Accumulated Amortization $ 91   81
Other      
Indefinite-lived Intangible Assets [Line Items]      
Estimated useful life 6 years    
Gross Carrying Amount $ 67   67
Accumulated Amortization $ 67   $ 67