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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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