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Significant Accounting Policies - Narrative (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Segment	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Business Organization And Significant Accounting Policies [Line Items]
Number of business segment | Segment			1
Accounts receivable, related parties	$ 12,800,000		$ 12,800,000		$ 10,500,000
Client performance period			5 years
Revenue	45,069,653	$ 28,248,929	$ 84,084,086	$ 60,174,674
Advance commissions amortization period			12 months
Variable Rate Fees
Business Organization And Significant Accounting Policies [Line Items]
Revenue	$ 1,300,000	$ 600,000	$ 2,200,000	$ 1,200,000

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