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Significant Accounting Policies - Narrative (Detail) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) Segment | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Business Organization And Significant Accounting Policies [Line Items] |  |  |
Number of business segment | Segment | 1 |  |
Accounts receivable, related parties | $ 12,300,000 |  | $ 10,500,000
Client performance period | 5 years |  |
Revenue | $ 39,014,433 | $ 31,925,745 |
Advance commissions amortization period | 12 months |  |
Variable Rate Fees |  |  |
Business Organization And Significant Accounting Policies [Line Items] |  |  |
Revenue | $ 900,000 | $ 700,000 |

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