Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Summary of Investments Valued Using NAV Per Share (Detail)

v3.21.2
Fair Value Measurements - Summary of Investments Valued Using NAV Per Share (Detail) - USD ($)
$ in Thousands
Sep. 30, 2021
Dec. 31, 2020
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value $ 9,108 $ 5,053
BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] | Measured at NAV [Member]    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value 336,174 215,082
Unfunded Commitments 3,410 4,860
BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] | Measured at NAV [Member] | Accrued Performance Allocations [Member]    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value 301,910 199,410
Unfunded Commitments 0 0
BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] | Measured at NAV [Member] | Company Sponsored Open-end Fund [Member]    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value 15,525 12,643
Unfunded Commitments 0 0
BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] | Measured at NAV [Member] | Company Sponsored Closed-end Funds [Member]    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value 12,346 332
Unfunded Commitments 58 58
BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] | Measured at NAV [Member] | Third Party Closed-end Funds [Member]    
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Line Items]    
Fair Value 6,393 2,697
Unfunded Commitments $ 3,352 $ 4,802