Stockholders' Equity - Additional Information (Detail) - USD ($)
$ in Thousands
 1 Months Ended 12 Months Ended
Jul. 12, 2013
Jul. 02, 2013
Nov. 30, 2015
Aug. 31, 2015
Jun. 30, 2015
May. 31, 2015
Mar. 31, 2015
Feb. 28, 2015
Nov. 30, 2013
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Class Of Stock [Line Items]                        
Partnership distributions, amount                   $ 5,546 $ 5,242 $ 29,317
Amount distributed to existing partners                   10,000    
Distributions of partner incentive allocations of net income                   $ 18,568 $ 14,266 $ 12,104
2012 Equity Incentive Plan                        
Class Of Stock [Line Items]                        
Restricted stock units granted       966,510                
Restricted stock units granted description                   Twenty-five percent of the restricted stock units granted vest and settle on each of the first, second, third and fourth anniversaries of the grant date.    
2012 Equity Incentive Plan | First Anniversary                        
Class Of Stock [Line Items]                        
Restricted stock, vesting percentage       25.00%                
2012 Equity Incentive Plan | Second Anniversary                        
Class Of Stock [Line Items]                        
Restricted stock, vesting percentage       25.00%                
2012 Equity Incentive Plan | Third Anniversary                        
Class Of Stock [Line Items]                        
Restricted stock, vesting percentage       25.00%                
2012 Equity Incentive Plan | Fourth Anniversary                        
Class Of Stock [Line Items]                        
Restricted stock, vesting percentage       25.00%                
Class A Common Stock                        
Class Of Stock [Line Items]                        
Common stock issued 718,603 4,790,684                   5,509,000
Exchange of Class B common stock for Class A common stock                   222,000 246,000 2,013,000
Class B Common Stock                        
Class Of Stock [Line Items]                        
Common stock issued               126,616        
Exchange of Class B common stock for Class A common stock                   (211,000) (246,000) (2,013,000)
Restricted stock units granted                   966,510    
Class B Common Stock | Jamison                        
Class Of Stock [Line Items]                        
Common stock issued         258,578              
Class B Common Stock | Resale And Registration Rights Agreement                        
Class Of Stock [Line Items]                        
Exchange of Class B common stock for Class A common stock     77,116 65,477   50,000 18,000          
Death of Chief Executive Officer | Class B Common Stock                        
Class Of Stock [Line Items]                        
Exchange of Class B common stock for Class A common stock                 2,013,677      
Silvercrest L.P                        
Class Of Stock [Line Items]                        
Accrued partner incentive allocations                   $ 18,535 $ 18,653 $ 14,196