Marketable Securities - Summary of Company's Investment Securities (Detail) - BRIDGE INVESTMENT GROUP HOLDINGS LLC [Member] - USD ($) $ in Thousands  | 
6 Months Ended | 12 Months Ended | 
|---|---|---|
Jun. 30, 2021  | 
Dec. 31, 2020  | 
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| Marketable Securities [Line Items] | ||
| Cost | $ 5,068 | $ 5,014 | 
| Unrealized Gains | 81 | 39 | 
| Unrealized Losses | (16) | |
| Fair Value | 5,133 | 5,053 | 
| Exchange Traded Funds [Member] | ||
| Marketable Securities [Line Items] | ||
| Cost | 715 | 713 | 
| Unrealized Gains | 21 | 23 | 
| Fair Value | 736 | 736 | 
| Mutual Fund [Member] | ||
| Marketable Securities [Line Items] | ||
| Cost | 4,353 | 4,301 | 
| Unrealized Gains | 60 | 16 | 
| Unrealized Losses | (16) | |
| Fair Value | $ 4,397 | $ 4,317 | 
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- Definition Marketable securities, cost. No definition available. 
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- Definition Marketable securities unrealized gains. No definition available. 
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available. 
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