Note Receivable - Schedule of Fair Value Measurement Inputs and Valuation Techniques (Detail)	Dec. 31, 2020	Dec. 31, 2019 yr
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument Interest Rate	2.17%
Notes Receivable | Risk-free Rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument Interest Rate		1.90%
Notes Receivable | Exercise Price of Underlying Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments Measurement Input		1.998
Notes Receivable | Share Price of Underlying Security
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments Measurement Input		1.90
Notes Receivable | Volatility
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Instrument Interest Rate		71.50%
Notes Receivable | Remaining Life (in years)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments Measurement Input		1.0