Quarterly report pursuant to Section 13 or 15(d)

Equity - Additional Information (Detail)

v3.20.2
Equity - Additional Information (Detail) - USD ($)
$ in Thousands
1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2020
May 31, 2020
Mar. 31, 2020
Feb. 29, 2020
Jun. 30, 2020
Mar. 31, 2020
Jun. 30, 2019
Mar. 31, 2019
Jun. 30, 2020
Jun. 30, 2019
Class Of Stock [Line Items]                    
Partnership distributions, amount         $ 2,798   $ 3,474   $ 5,024 $ 5,759
Distributions of partner incentive allocations of net income                 27,240 27,199
Class B Common Stock                    
Class Of Stock [Line Items]                    
Share conversion, Shares   7,355     (12,000) (176,000) (87,000) (17,000)    
Issuance of common stock   9,546           2,000    
Class B Common Stock | Resale And Registration Rights Agreement                    
Class Of Stock [Line Items]                    
Share conversion, Shares 5,400 7,355 20,662 155,224            
Class A Common Stock                    
Class Of Stock [Line Items]                    
Share conversion, Shares         12,000 176,000 87,000 17,000    
Issuance of common stock   1,896                
Silvercrest L.P                    
Class Of Stock [Line Items]                    
Accrued partner incentive allocations         $ 5,557   $ 6,261   $ 12,934 $ 11,651