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Fair Value Measurements - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Other-than-temporary impairment losses	$ 0	$ 0
Fair value assets, level 1 to level 2 transfers, amount	0
Fair value assets, level 2 to level 1 transfers, amount	0
Fair value assets, transfers into level 3	0
Fair value liabilities, level 1 to Level 2 transfers amount	0
Fair value liabilities, level 2 to Level 1 transfers amount	0
Fair value liabilities, transfers into level 3	0
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt Instrument, expected term measurement input		8 months 12 days
Level 3 | Measurement Input, Stock Price Volatility
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument measurement input		30
Level 3 | Measurement Input, Risk Free Interest Rate
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument measurement input		1.6
Level 3 | Measurement Input, Expected Dividend Payment
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument measurement input		0
Level 3 | Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Change in fair value	$ 2,200,000

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings.

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