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Significant Accounting Policies - Narrative (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) Segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Business Organization And Significant Accounting Policies [Line Items]
Number of business segment | Segment			1
Accounts receivable, related parties	$ 8,500,000		$ 8,500,000		$ 10,700,000
Client performance period			5 years
Revenue	28,248,929	$ 33,545,016	$ 60,174,674	$ 66,124,389
Advance commissions amortization period			12 months
Variable Rate Fees
Business Organization And Significant Accounting Policies [Line Items]
Revenue	$ 600,000	$ 400,000	$ 1,200,000	$ 800,000

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