v3.21.2

Summary of Significant Accounting Policies - Summary of Significant Unobservable Inputs Used to Estimate Fair Value of Earnout Liability (Detail) - Fair Value Inputs Level3 [Member]	Feb. 07, 2020 $ / shares	Sep. 30, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Weighted Average Assumption Used, Expected IPO date	Apr. 15, 2020
Range, Expected IPO date	March 2020 through May 2020
Measurement Input, Price Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Weighted Average Assumption Used, Company's net asset value per diluted share	$ 21.30
Weighted Average [Member] | Measurement Input, Price Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Weighted Average Assumption Used, Peer stock price volatility	20.0	40.0
Minimum | Measurement Input, Price Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Weighted Average Assumption Used, Peer stock price volatility	16.22	26.11
Maximum | Measurement Input, Price Volatility [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Weighted Average Assumption Used, Peer stock price volatility	23.09	56.85

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Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure.

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