Annual report pursuant to Section 13 and 15(d)

Equity - Additional Information (Detail)

v3.10.0.1
Equity - Additional Information (Detail) - USD ($)
$ in Thousands
 1 Months Ended 12 Months Ended
Dec. 31, 2018
Nov. 30, 2018
Sep. 30, 2018
Aug. 31, 2018
Jun. 30, 2018
May 31, 2018
Apr. 30, 2018
Mar. 31, 2018
Jan. 31, 2018
Nov. 30, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Class Of Stock [Line Items]                          
Partnership distributions, amount                     $ 6,773 $ 6,205 $ 5,761
Distributions of partner incentive allocations of net income                     $ 24,935 $ 21,177 $ 18,827
Class B Common Stock                          
Class Of Stock [Line Items]                          
Share conversion, Shares                     (374,000) (63,000) (84,000)
Issuance of Class B shares, Shares       241,627 6,289 948         6,000 13,000  
Class B Common Stock | Resale And Registration Rights Agreement                          
Class Of Stock [Line Items]                          
Share conversion, Shares 108,319 64,142 17,666 22,285   24,732 20,000 85,286 31,650 85,286      
Class A Common Stock                          
Class Of Stock [Line Items]                          
Share conversion, Shares                     374,000 63,000 84,000
Issuance of Class B shares, Shares           1,896              
Silvercrest L.P                          
Class Of Stock [Line Items]                          
Accrued partner incentive allocations                     $ 27,197 $ 25,101 $ 20,238